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p. 13704-13711
Received: 17 October 2012; in revised form: 9 November 2012 / Accepted: 12 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (642 KB) Abstract: Considerable efforts have been devoted to control and maintain the sustained release of proteins. In this experiment, we used bovine serum albumin-fluorescein isothiocyanate (BSA-FITC) as a model protein to explore the potential utility of a chitosan and glycerol phosphate disodium salt (GP) hydrogel as a protein drug depot. The mixing of chitosan and GP solutions (0, 10, 20 and 30 wt%) formed a liquid at room temperature. At 37 °C, however, the chitosan/GP solutions formed hydrogels through an electrostatic crosslinking process. This electrostatic interaction between the chitosan, cationic amine group, and GP, anionic phosphate group, was confirmed by the changes of zeta potentials and particle sizes of this solution. The electrostatic interaction depended both on the GP ratios in chitosan and the incubation time of chitosan/GP solutions. Furthermore, BSA-FITC-loaded chitosan/GP hydrogels were examined for their ability as potential depots for the BSA drugs. Hence, when observed, the BSA-FITC-loaded chitosan/GP hydrogels showed an in vitro sustained release profile of BSA up to 14 days. Collectively, our results show that the chitosan/GP hydrogels described here, can serve as depots for BSA drugs.
p. 13712-13726
Received: 12 October 2012; in revised form: 10 November 2012 / Accepted: 13 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (901 KB) | Download XML Full-text | Abstract: This study was undertaken in order to investigate the effect of chronic treatment with 5′-chloro-5′-deoxy-(±)-ENBA, a potent and highly selective agonist of human adenosine A1 receptor, on thermal hyperalgesia and mechanical allodynia in a mouse model of neuropathic pain, the Spared Nerve Injury (SNI) of the sciatic nerve. Chronic systemic administration of 5′-chloro-5′-deoxy-(±)-ENBA (0.5 mg/kg, i.p.) reduced both mechanical allodynia and thermal hyperalgesia 3 and 7 days post-SNI, in a way prevented by DPCPX (3 mg/kg, i.p.), a selective A1 adenosine receptor antagonist, without exerting any significant change on the motor coordination or arterial blood pressure. In addition, a single intraperitoneal injection of 5′-chloro-5′-deoxy-(±)-ENBA (0.5 mg/kg, i.p.) 7 days post-SNI also reduced both symptoms for at least two hours. SNI was associated with spinal changes in microglial activation ipsilaterally to the nerve injury. Activated, hypertrophic microglia were significantly reduced by 5′-chloro-5′-deoxy-(±)-ENBA chronic treatment. Our results demonstrated an involvement of adenosine A1 receptor in the amplified nociceptive thresholds and in spinal glial and microglial changes occurred in neuropathic pain, without affecting motor coordination or blood pressure. Our data suggest a possible use of adenosine A1 receptor agonist in neuropathic pain symptoms.
p. 13727-13739
Received: 22 October 2012; in revised form: 13 November 2012 / Accepted: 14 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (685 KB) Abstract: Four ammonium and imidazolium ionic liquids (ILs) have been synthesized and screened against the T98G cell line (brain cancer) and HEK normal cells. Treatment induced metabolic cell death (MTT), growth inhibition, clonogenic inhibition were studied as cellular response parameters. Treatment with ILs enhanced growth inhibition and cell death in a concentration dependent manner in both the T98G and HEK cell lines. At higher concentrations (>0.09 mg/mL) the cytotoxic effects of the ILs were highly significant. An inhibitory effect on clonogenic capacity was also observed after cell treatment. Amongst all ILs; IL 4 (BMIMCl) exhibited potent activity against T98G brain cancer cells. Despite potent in-vitro activity, all ILs exhibited less cytotoxicity against the normal human HEK cells at all effective concentrations.
p. 13740-13758
Received: 24 September 2012; in revised form: 15 November 2012 / Accepted: 19 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (877 KB) Abstract: Within this study, a unique 3D structure-based pharmacophore model of the enzyme glyoxalase-1 (Glo-1) has been revealed. Glo-1 is considered a zinc metalloenzyme in which the inhibitor binding with zinc atom at the active site is crucial. To our knowledge, this is the first pharmacophore model that has a selective feature for a “zinc binding group” which has been customized within the structure-based pharmacophore model of Glo-1 to extract ligands that possess functional groups able to bind zinc atom solely from database screening. In addition, an extensive 2D similarity search using three diverse similarity techniques (Tanimoto, Dice, Cosine) has been performed over the commercially available “Zinc Clean Drug-Like Database” that contains around 10 million compounds to help find suitable inhibitors for this enzyme based on known inhibitors from the literature. The resultant hits were mapped over the structure based pharmacophore and the successful hits were further docked using three docking programs with different pose fitting and scoring techniques (GOLD, LibDock, CDOCKER). Nine candidates were suggested to be novel Glo-1 inhibitors containing the “zinc binding group” with the highest consensus scoring from docking.
p. 13759-13768
Received: 25 October 2012; in revised form: 13 November 2012 / Accepted: 14 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (289 KB) | Abstract: We describe the palladium-catalyzed multicomponent synthesis of 2-imidazolines. This reaction proceeds via the coupling of imines, acid chlorides and carbon monoxide to form imidazolinium carboxylates, followed by a decarboxylation. Decarboxylation in CHCl3 is found to result in a mixture of imidazolinium and imidazolium salts. However, the addition of benzoic acid suppresses aromatization, and generates the trans -disubstituted imidazolines in good yield. Combining this reaction with subsequent nitrogen deprotection provides an overall synthesis of imidazolines from multiple available building blocks.
p. 13769-13786
Received: 11 October 2012; in revised form: 19 November 2012 / Accepted: 20 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (443 KB) | Download XML Full-text Abstract: In this study, we investigated the anti-inflammatory effects of red ginseng marc oil (RMO) in the RAW 264.7 macrophage cell line. RMO was prepared by a supercritical CO2 extraction of waste product generated after hot water extraction of red ginseng. RMO significantly inhibited the production of oxidative stress molecules such as nitric oxide and reactive oxygen species in lipopolysaccharide (LPS)-activated RAW 264.7 cells. Levels of inflammatory targets including prostaglandin E2, tumor necrosis factor-α, interleukin (IL)-1β and IL-6 were also reduced after the treatment with RMO. In addition, RMO diminished the expressions of inducible nitric oxide synthase and cyclooxygenase 2 at both mRNA and protein levels. Blockade of nuclear translocation of the p65 subunit of nuclear factor κB (NFκB) was also observed after the treatment of RMO. Furthermore, RMO decreased the phosphorylations of p38 mitogen-activated protein kinase (MAPK) and its upstream kinases including MAPK kinases 3/6 (MKK3/6) and TAK 1 (TGF-β activated kinase 1). Gas chromatographic analysis on RMO revealed that RMO contained about 10% phytosterols including sitosterol, stigmasterol and campesterol which may contribute to the anti-inflammatory properties of RMO. Taken together, these results suggest that the anti-inflammatory effect of RMO in LPS-induced RAW 264.7 macrophages could be associated with the inhibition of NFκB transcriptional activity, possibly via blocking the p38 MAPK pathway.
p. 13787-13794
Received: 19 October 2012; in revised form: 2 November 2012 / Accepted: 5 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (320 KB) | Download XML Full-text Abstract: Methyl 1-aryl-3-cinnamoyl-4,5-dioxo-4,5-dihydro-1H -pyrrole-2-carboxylates interact with 3-(arylamino)-1H -inden-1-ones to give the corresponding 1,1'-diaryl-3'-cinnamoyl-4'-hydroxy-1H -spiro[indeno[1,2-b]pyrrole-3,2'-pyrrole]-2,4,5'(1'H )-triones in good yields.
p. 13795-13812
Received: 9 July 2012; in revised form: 5 November 2012 / Accepted: 13 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (260 KB) | Download XML Full-text Abstract: Sensorial analysis of pineapple breads (conventionally baked, Cpb; fully baked frozen, Fpb and partially baked, Ppb) showed no significant differences in terms of aroma and taste. On the contrary, the scores for the overall quality between the partially baked and conventionally baked breads showed significant (p < 0.05) differences. At the same time, headspace analysis using a solid-phase microextraction (SPME) method identified 59 volatile compounds. The results of the aroma extracts dilution analysis (AEDA) revealed 19 most odour-active compounds with FD factors in the range of 32–128 as the key odourants of the pineapple breads. Further analysis of the similarities and differences between the pineapple breads in terms of the key odourants were carried out by the application of PLS-DA and PLS-regression coefficients. Results showed that Ppb exhibited strong positive correlations with most of the volatile- and non-volatile compounds, while the Cpb showed significant positive correlations with hexanal and 4-hydroxy-2,5-dimethyl-3(2H )-furanone, and the Fpb had strong positive correlations with lactic acid, benzoic acid, benzaldehyde and ethyl propanoate.
p. 13813-13824
Received: 17 September 2012; in revised form: 15 November 2012 / Accepted: 16 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (209 KB) | Download XML Full-text Abstract: Lipases from Geotrichum candidum 4013 (extracellular lipase and cell-bound lipase) were immobilized by adsorption on chitosan beads. The enzyme preparations were tested in the synthesis of ester prodrugs from racemic 9-(2,3-dihydroxypropyl)adenine in dimethylformamide with different vinyl esters (acetate, butyrate, decanoate, laurate, palmitate). The transesterification activities of these immobilized enzymes were compared with commercially available lipases (lipase from hog pancreas, Aspergillus niger , Candida antarctica , Pseudomonas fluorescens ). Lipase from Candida antarctica was found to be the most efficient enzyme regarding chemical yield of the desired products, while transesterification by lipase from Aspergillus niger resulted in lower yields.
p. 13825-13843
Received: 17 October 2012; in revised form: 16 November 2012 / Accepted: 16 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (285 KB) | Download XML Full-text Abstract: Here we used solid-phase methods to prepare oligonucleotides carrying fibrin/ filaggrin citrullinated peptides. Post-synthetic conjugation protocols were successfully applied for the synthesis of oligonucleotides carrying small peptides. A stepwise protocol using acid treatment for the final deprotection allowed the preparation of polypyrimidine oligonucleotides carrying longer and arginine-rich peptides. An ELISA-based test using the oligonucleotide-citrullinated peptide conjugates was developed for the detection of anti-citrullinated protein/peptide antibodies in human serum from rheumatoid arthritis patients.
p. 13844-13855
Received: 11 October 2012; in revised form: 16 November 2012 / Accepted: 19 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (310 KB) | Download XML Full-text Abstract: A reverse phase ultra performance liquid chromatography and photodiode array (UPLC-PDA) detection method was established for the determination of six alkaloids in Zoagumhwan (ZGW), and further for investigating the influence of nonpolar substances on the extraction efficiency of these alkaloids. The method was based on a BEH C18 (50 mm × 2.1 mm, 1.7 μm) column and mobile phase of aqueous phosphoric acid and acetonitrile including 0.05% buffer solution under gradient elution. ZGW samples of ZGW I, II, III and IV were obtained and prepared by pre-processing the crude materials of Coptidis rhizoma and Evodiae fructus using four technologies, namely direct water decoction, removal of nonpolar substances in Evodiae fructus by supercritical fluid extraction (SFE), removal of nonpolar substances in ZGW by SFE and removal of nonpolar substances in ZGW by steam distillation. The developed and validated UPLC-PDA method was precise, accurate and sensitive enough based on the facts that the six alkaloids showed good regression (r > 0.9998), the limit of detections and quantifications for six alkaloids were less than 28.8 and 94.5 ng/mL, respectively, and the recovery was in the range of 98.56%–103.24%. The sequence of the total contents of six alkaloids in these samples was ZGW II > ZGW IV > ZGW III > ZGW I. ZGW II, in which nonpolar substances, including essential oils, were firstly removed from Evodiae fructus by SFE, had the highest content of the total alkaloids, indicating that extraction efficiency of the total alkaloids could be remarkably increased after Evodiae fructus being extracted by SFE.
p. 13856-13863
Received: 5 November 2012; in revised form: 17 November 2012 / Accepted: 20 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (222 KB) | Download XML Full-text Abstract: A series of 4-aryl-6-methyl-3,4-dihydro-2H -pyrano[3,2-c ]quinolin-2,5(6H )-diones were synthesized via the three-component reactions of aromatic aldehydes, 4-hydroxy-1-methylquinolin-2(1H )-one, and Meldrum’s acid catalyzed by L-proline. The structures of the products were identified by spectroscopic analysis. A mechanism for this three-component reaction catalyzed by L-proline was proposed.
p. 13864-13878
Received: 22 October 2012; in revised form: 31 October 2012 / Accepted: 19 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (270 KB) | Download XML Full-text | Abstract: The Weinreb amides 2a ,b were prepared from the α,α -dimethoxyacetic acids 1c ,d . A number of representative nucleophilic additions (RMgX and RLi) on 2 afforded α -ketoacetals 3a –j in 70–99% yield. These compounds represent a versatile arrangement of functional groups of significant synthetic value, as demonstrated in the synthesis of (±)-salbutamol.
p. 13879-13890
Received: 8 October 2012; in revised form: 31 October 2012 / Accepted: 20 November 2012 / Published: 22 November 2012
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| Download PDF Full-text (351 KB) | Download XML Full-text Abstract: Spiro-N,N -ketal 5 , consisting of a phthaloperine heterocyclic ring and a naphtha[1,8-ef][1,4]diazepine ring, was obtained along with spiro-N,N -ketal 2 via 2,2-condensation in the reaction of ninhydrin with naphthalene-1,8-diamine. Their molecular structures were elucidated by X-ray crystal structural analysis. Aside from these spiro compounds, the diazapleiadiene compound 3 formed by 1,2-condensation and the 1,4-isoquinolinedione compound 4 arising from ring expansion were isolated. When isatin was reacted with naphthalene-1,8-diamine, spiro-N ,N -ketal 6 and the two 1H -perimidine-based compounds 7 and 8 were isolated. Compound 8 was revealed to undergo a fast dynamic prototropic tautomerization in solution. Plausible mechanisms of the formation of the products are proposed.
p. 13891-13909
Received: 19 October 2012; in revised form: 14 November 2012 / Accepted: 16 November 2012 / Published: 23 November 2012
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| Download PDF Full-text (387 KB) | Download XML Full-text Abstract: A series of new monoazo disperse dyes containing pyrazolopyrimidine moieties was synthesized by coupling malononitrile or 3-aminocrotononitrile with 4-hydroxy- benzenediazonium chloride. Treatment of the resulting products with hydrazine hydrate yields the corresponding 4-arylazoaminopyrazoles, which then react with either 2,4-pentanedione and enaminonitriles or aryl-substituted enaminoketones to give the target pyrazolopyrimidine monoazo disperse dyes. Structural assignments of the dyes were made using both NMR spectroscopic and X-ray crystallographic methods. A high temperature dyeing method, by microwave irradiation, was employed with polyester fabrics. Most of the dyed fabrics tested displayed moderate light fastness and excellent washing and perspiration fastness levels.
p. 13910-13916
Received: 19 October 2012; in revised form: 16 November 2012 / Accepted: 19 November 2012 / Published: 23 November 2012
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| Download PDF Full-text (224 KB) | Download XML Full-text Abstract: A new prenylated naphthoquinoid, named (3R ,4aR ,10bR )-3,10-dihydroxy-2,2-dimethyl-3,4,4a,10b-tetrahydro-2H -naphtho[1,2-b]-pyran-5H -6-one (1 ), was isolated from the aerial parts of Clinopodium chinense (Benth.) O. Kuntze, together with six known compounds: apigenin (2 ), luteolin (3 ), neoeriocitrin (4 ), naringenin (5 ), narirutin (6 ), and didymin (7 ). Neoeriocitrin was isolated for the first time from the species C. chinense . Their structures were elucidated by spectroscopic methods, including 1D, 2D (1 H-1 H-COSY, HSQC, HMBC and NOESY) NMR, HR-ESI-MS. The absolute configuration of 1 was determinated using the CD method. We highlight that the structure of 1 is characterized by a rarely seen prenylated naphthoquinoid framework.
p. 13917-13922
Received: 26 September 2012; in revised form: 15 November 2012 / Accepted: 16 November 2012 / Published: 23 November 2012
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| Download PDF Full-text (189 KB) | Download XML Full-text Abstract: Four phenolic compounds were isolated from the roots of Sanguisorba officinalis L. by silica gel column chromatography and preparative HPLC. On the basis of chemical and spectroscopic methods, their structures were identified as methyl 4-O -β-D-glucopyranosy-5-hydroxy-3-methoxylbenzoate (1 ), 3,3′,4′-tri-O -methylellagic acid (2 ), fisetinidol-(4α-8)-catechin (3 ), and (+)-catechin (4 ). Compound 1 is a new phenolic glycoside and compounds 2 and 3 were isolated from the Sanguisorba genus for the first time. Compounds 1 –4 were also assayed for their antioxidant activities using the DPPH free radical assay.
p. 13923-13936
Received: 25 October 2012; in revised form: 9 November 2012 / Accepted: 16 November 2012 / Published: 23 November 2012
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| Download PDF Full-text (365 KB) | Abstract: Ultrafast near-infrared absorption spectroscopy was used to investigate the influence of film morphology and excitation photon energy on the charge recombination (CR) dynamics in the initial nanosecond timescale in the P3HT/PC61 BM blend films. With reference to the CS2 -cast films, the solvent vapor annealed (SVA) ones show 2–3-fold improvement in hole mobility and more than 5-fold reduction in the polymer-localized trap states of holes. At Dt = 70 ps, the hole mobility (m h ) and the bimolecular CR rate (g bi ) of the SVA films are m h = 8.7 × 10−4 cm2 ×s−1 ×V−1 and g bi = 4.5 × 10−10 cm3 ×s−1 , whereas at Dt = 1 ns they drop to 8.7 × 10−5 cm2 ×s−1 ×V−1 and 4.6 × 10−11 cm3 ×s−1 , respectively. In addition, upon increasing the hole concentration, the hole mobility increases substantially faster under the above-gap photoexcitation than it does under the band-gap photoexcitation, irrespective of the film morphologies. The results point to the importance of utilizing the photogenerated free charges in the early timescales.
p. 13937-13947
Received: 9 November 2012; in revised form: 15 November 2012 / Accepted: 19 November 2012 / Published: 23 November 2012
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| Download PDF Full-text (2151 KB) | Abstract: The aim of the present study was to evaluate the hepatoprotective activity of lantadene A against acetaminophen-induced liver toxicity in mice was studied. Activity was measured by monitoring the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and bilirubin, along with histo-pathological analysis. Silymarin was used as positive control. A bimodal pattern of behavioural toxicity was exhibited by the lantadene A-treated group at the beginning of the treatment. However, treatment with lantadene A and silymarin resulted in an increase in the liver weight compared with the acetaminophen treated group. The results of the acetaminophen-induced liver toxicity experiments showed that mice treated with lantadene A (500 mg/kg) showed a significant decrease in the activity of ALT, AST and ALP and the level of bilirubin, which were all elevated in the acetaminophen treated group (p < 0.05). Histological studies supported the biochemical findings and a maximum improvement in the histoarchitecture was seen. The lantadene A-treated group showed remarkable protective effects against histopathological alterations, with comparable results to the silymarin treated group. The current study confirmed the hepatoprotective effects of lantadene A against the model hepatotoxicant acetaminophen, which is likely related to its potent antioxidative activity.
p. 13948-13959
Received: 10 September 2012; in revised form: 17 November 2012 / Accepted: 20 November 2012 / Published: 26 November 2012
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| Download PDF Full-text (394 KB) | Abstract: The potential value of multiplexed positron emission tomography (PET) tracers in mice with turpentine-induced inflammation was evaluated and compared with 2-[18 F]fluoro-2-deoxy-D-glucose ([18 F]FDG) for glucose metabolism imaging. These PET tracers included [18 F]fluoromethylcholine ([18 F]FCH) for choline metabolism imaging, (S-[11 C]methyl)-D-cysteine ([11 C]DMCYS) for amino acid metabolism imaging, [11 C]bis(zinc(II)-dipicolylamine) ([11 C]DPA-Zn2+ ) for apoptosis imaging, 2-(4-N -[11 C]-methylaminophenyl)-6-hydroxybenzothiazole ([11 C]PIB) for β amyloid binding imaging, and [18 F]fluoride (18 F− ) for bone metabolism imaging. In mice with turpentine-induced inflammation mice, the biodistribution of all the tracers mentioned above at 5, 15, 30, 45, and 60 min postinjection was determined. Also, the time-course curves of the tracer uptake ratios for inflammatory thigh muscle (IM) to normal uninflammatory thigh muscle (NM), IM to blood (BL), IM to brain (BR), and IM to liver (LI) were acquired, respectively. Moreover, PET imaging with the tracers within 60 min postinjection on a clinical PET/CT scanner was also conducted. [18 F]FDG and 18 F− showed relatively higher uptake ratios for IM to NM, IM to BL, IM to BR, and IM to LI than [18 F]FCH, [11 C]DPA-Zn2+ , [11 C]DMCYS and [11 C]PIB, which were highly consistent with the results delineated in PET images. The results demonstrate that 18 F− seems to be a potential PET tracer for inflammation imaging. [18 F]FCH and [11 C]DMCYS, with lower accumulation in inflammatory tissue than [18 F]FDG, are not good PET tracers for inflammation imaging. As a promising inflammatory tracer, the chemical structure of [11 C]DPA-Zn2+ needs to be further optimized.
p. 13960-13968
Received: 28 September 2012; in revised form: 6 November 2012 / Accepted: 8 November 2012 / Published: 26 November 2012
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| Download PDF Full-text (433 KB) Abstract: A new ursane-type nortriterpenoid, (11S ,12S )-4-methyl-11,12-epoxy-2-hydroxy-3-oxoursa-1,4-dine-28-oic acid γ -lactone (1 ), named ulmoidol A, together with ten known compounds: ulmoidol (2 ), corosolic acid (3 ), 2α ,3α -dihydroxy-24-nor-4(23),12-oleanadien-28-oic acid (4 ), oleanolic acid (5 ), ursolic acid (6 ), cycloart-3β , 25-diol (7 ), foliasalacioside B1 (8 ), (6R ,7E,9R )-9-hydroxy-4,7-megastigmadien-3-one-9-O-α -L-arabinopyranosyl-(1→6)-β -D-glucopyranoside (9 ), (6R ,7E,9R )-9-hydroxy-4,7-megastigma-dien-3-one-9-O -β -D-xylopyranosyl-(1→6)-β -D-glucopyranoside (10 ), and quercetin 3-O -sambubioside (11 ) were isolated from the leaves of Eucommia ulmoides Oliv. The structure of compound 1 was determined by extensive spectroscopic analysis, and its absolute configuration was determined by CD experiments and a computational method. Compounds 3 , 4 , 7 –10 were isolated from this plant for the first time. Compounds 3 and 4 showed inhibition to PTPIB activities, with IC50 values of 0.69 and 3.98 μM, respectively.
p. 13969-13988
Received: 4 September 2012; in revised form: 2 November 2012 / Accepted: 12 November 2012 / Published: 26 November 2012
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| Download PDF Full-text (1213 KB) Abstract: Twelve novel intrinsically colored wholly aromatic azopolyamide-hydrazides containing various proportions of para - and meta -phenylene units were successfully synthesized by a low temperature (−10 °C) solution polycondensation reaction of either 4-amino-3-hydroxybenzhydrazide (4A3HBH) or 3-amino-4-hydroxybenzhydrazide (3A4HBH) with an equimolar amount of either 4,4'-azodibenzoyl chloride (4,4'ADBC), 3,3'-azodibenzoyl chloride (3,3'ADBC), or mixtures of various molar ratios of 4,4'ADBC and 3,3'ADBC in anhydrous N,N-dimethyl acetamide (DMAc) containing 3% (wt/v) LiCl as a solvent. The structures of the polymers were proven by elemental analysis, FTIR, 1 H- and 13 C-NMR spectroscopy. The polymers’ properties were strongly affected by their various structures. The intrinsic viscosities of the polymers were ranged from 0.7 to 4.75 dL g−1 and increased with the para -phenylene units content. The polymers are partially soluble in DMAc, dimethyl formamide (DMF) and N -methyl-2-pyrrolidone (NMP). Their solubility increases with the introduction of meta -phenylene moieties into the polymer chains. The polymers exhibit a great affinity for water sorption. Their hydrophilicity increases as a function of the content of meta -phenylene rings incorporated into the polymer. Mechanical properties of the polymer films are improved markedly by substitution of para -phenylene units for meta -phenylene units. The completely para -oriented type polymer has the best thermal and thermo-oxidative stability relative to those of the other polymers.
p. 13989-14001
Received: 18 October 2012; in revised form: 13 November 2012 / Accepted: 16 November 2012 / Published: 26 November 2012
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| Download PDF Full-text (255 KB) | Download XML Full-text Abstract: Deltamethrin, a member of the pyrethroids, one of the safest classes of pesticides, is among some of the most popular and widely used insecticides in the World. Our objective was to synthesize an oxabicyclolactone 6 and five novel pyrethroids 8 –12 from readily available furfural and D-mannitol, respectively, and evaluate their biological activity against four insect species of economic importance namely A. obtectus , S. zeamais , A. monuste orseis , and P. americana . A concise and novel synthesis of 6,6-dimethyl-3-oxabicyclo[3.1.0]hexan-2-one (6 ) from furfural is described. Photochemical addition of isopropyl alcohol to furan-2(5H )-one afforded 4-(1'-hydroxy-1'-methylethyl)tetrahydro-furan-2-one (3 ). The alcohol 3 was directly converted into 4-(1'-bromo-1'-methylethyl)-tetrahydrofuran-2-one (5 ) in 50% yield by reaction with PBr3 and SiO2 . The final step was performed by cyclization of 5 with potassium tert- butoxide in 40% yield. The novel pyrethroids 8 –12 were prepared from methyl (1S ,3S )-3-formyl-2,2-dimethylcyclopropane-1-carboxylate (7a ) by reaction with five different aromatic phosphorous ylides. Compounds 6 –12 presented high insecticidal activity, with 6 and 11 being the most active. Compound 6 killed 90% of S. zeamais and 100% of all the other insects evaluated. Compound 11 killed 100% of all insects tested.
p. 14002-14014
Received: 8 October 2012; in revised form: 16 November 2012 / Accepted: 18 November 2012 / Published: 26 November 2012
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| Download PDF Full-text (235 KB) | Download XML Full-text Abstract: Two new furostanol saponins 1 –2 and three new sulphated glycosides 3a ,b and 4 were isolated from the underground parts of Ruscus aculeatus L., along with four known furostanol and one spirostanol saponins 5 –9 and three free sterols. All of the structures have been elucidated on the basis of spectroscopic data 1D and 2D NMR experiments, MS spectra and GC analyses.
p. 14015-14021
Received: 24 October 2012; in revised form: 22 November 2012 / Accepted: 23 November 2012 / Published: 27 November 2012
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| Download PDF Full-text (197 KB) | Download XML Full-text Abstract: Pestalafuranones A–E (compounds 1 –5 ), five new 2(5H )-furanones, have been isolated from cultures of an isolate of Pestalotiopsis besseyi . The structures of these compounds were elucidated mainly by analysis of their NMR spectroscopic data and HRESIMS experiments. Pestalafuranones A–C (compounds 1 –3 ) displayed weak inhibitory effects against HIV-1 replication in C8166 cells, whereas pestalafuranones D (4 ) and E (5 ) showed moderate antifungal activity against the plant pathogens Verticillium dahiae and Alternaria longipes .
p. 14022-14036
Received: 15 October 2012; in revised form: 14 November 2012 / Accepted: 15 November 2012 / Published: 27 November 2012
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| Download PDF Full-text (303 KB) Abstract: Thirteen structural analogs of two initial intermediates of the L-a-aminoadipate pathway of L-lysine biosynthesis in fungi have been designed and synthesized, including fluoro- and epoxy-derivatives of homoaconitate and homoisocitrate. Some of the obtained compounds exhibited at milimolar range moderate enzyme inhibitory properties against homoaconitase and/or homoisocitrate dehydrogenase of Candida albicans . The structural basis for homoisocitrate dehydrogenase inhibition was revealed by molecular modeling of the enzyme-inhibitor complex. On the other hand, the trimethyl ester forms of some of the novel compounds exhibited antifungal effects. The highest antifungal activity was found for trimethyl trans -homoaconitate, which inhibited growth of some human pathogenic yeasts with minimal inhibitory concentration (MIC) values of 16–32 mg/mL.
p. 14037-14045
Received: 28 August 2012; in revised form: 18 November 2012 / Accepted: 23 November 2012 / Published: 27 November 2012
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| Download PDF Full-text (212 KB) Abstract: Eight compounds were isolated from the water extract of Pu-erh tea and their structures were elucidated by NMR and MS as gallic acid (1 ), (+)-catechin (2 ), (−)-epicatechin (3 ), (−)-epicatechin-3-O -gallate (4 ), (−)-epigallocatechin-3-O -gallate (5 ), (−)-epiafzelechin- 3-O -gallate (6 ), kaempferol (7 ), and quercetin (8 ). Their in vitro antioxidant activities were assessed by the DPPH and ABTS scavenging methods with microplate assays. The relative order of DPPH scavenging capacity for these compounds was compound 8 > compound 7 > compound 1 > compound 6 > compound 4 ≈ compound 5 > compound 2 > VC (reference) > compound 3 , and that of ABTS scavenging capacity was compound 1 > compound 2 > compound 7 ≈ compound 8 > compound 6 > compound 5 > compound 4 > VC (reference) > compound 3 . The results showed that these phenolic compounds contributed to the antioxidant activity of Pu-erh tea.
p. 14046-14057
Received: 24 September 2012; in revised form: 30 October 2012 / Accepted: 20 November 2012 / Published: 27 November 2012
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| Download PDF Full-text (431 KB) | Abstract: Root extracts of Holostylis reniformis (Aristolochiaceae) yielded three new natural sesquiterpenes, a sesquiterpene with an unusual carbon skeleton, 4,5-seco-guaiane (7-epi -11-hydroxychabrolidione A, 1 ), a nine-membered lactone with new carbon skeleton (holostylactone, 2 ), and a new megastigmane [(6S ,7E )-6,9-dihydroxy-10-(2'-hydroxy-ethoxy)-4,7-megastigmadien-3-one, 3 ], together with bulnesol and sitosterol-3-O -β-D-glucopyranoside. The structures of these compounds were determined by spectroscopic analyses and B3LYP/STO-3G** theoretical studies.
p. 14058-14066
Received: 22 October 2012; in revised form: 18 November 2012 / Accepted: 23 November 2012 / Published: 27 November 2012
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| Download PDF Full-text (270 KB) Abstract: Two norcembranoidal diterpenes, 5-episinuleptolide acetate (1 ) and scabrolide D (2 ), were isolated from a Formosan octocoral identified as Sinularia sp. The structures of norcembranoids 1 and 2 were established by spectroscopic methods and by comparison of the spectral data with those of known analogues and 1 was proven to be a new natural product. Norcembranoid 1 was found to exhibit cytotoxicity toward a panel of tumor cells.
p. 14067-14090
Received: 23 November 2012; in revised form: 26 November 2012 / Accepted: 26 November 2012 / Published: 28 November 2012
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| Download PDF Full-text (617 KB) | Download XML Full-text Abstract: Fluorescence, the absorption and re-emission of photons with longer wavelengths, is one of those amazing phenomena of Nature. Its discovery and utilization had, and still has, a major impact on biological and biomedical research, since it enables researchers not just to visualize normal physiological processes with high temporal and spatial resolution, to detect multiple signals concomitantly, to track single molecules in vivo , to replace radioactive assays when possible, but also to shed light on many pathobiological processes underpinning disease states, which would otherwise not be possible. Compounds that exhibit fluorescence are commonly called fluorochromes or fluorophores and one of these fluorescent molecules in particular has significantly enabled life science research to gain new insights in virtually all its sub-disciplines: Green Fluorescent Protein. Because fluorescent proteins are synthesized in vivo , integration of fluorescent detection methods into the biological system via genetic techniques now became feasible. Currently fluorescent proteins are available that virtually span the whole electromagnetic spectrum. Concomitantly, fluorescence imaging techniques were developed, and often progress in one field fueled innovation in the other. Impressively, the properties of fluorescence were utilized to develop new assays and imaging modalities, ranging from energy transfer to image molecular interactions to imaging beyond the diffraction limit with super-resolution microscopy. Here, an overview is provided of recent developments in both fluorescence imaging and fluorochrome engineering, which together constitute the “fluorescence toolbox” in life science research.
p. 14091-14098
Received: 16 October 2012; in revised form: 21 November 2012 / Accepted: 23 November 2012 / Published: 28 November 2012
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| Download PDF Full-text (204 KB) | Download XML Full-text Abstract: From the ethyl acetate extract of the culture broth of Talaromyces verruculosus , a rhizosphere fungus of Stellera chamaejasme L., (−)-8-hydroxy-3-(4-hydroxypentyl)-3,4-dihydroisocoumarin (1 ) and (E )-3-(2,5-dioxo-3-(propan-2-ylidene)pyrrolidin-1-yl)acrylic acid (2 ) were isolated and evaluated for their antimicrobial activities. Their structures were elucidated by UV, IR, MS, 1 H-NMR, 13 C-NMR and 2D NMR spectra. Compound 1 exhibited the significant activities in vitro against two strains of bacteria and four strains of fungi. Compound 2 gave slight activities on the fungi at 100 µg mL−1 , but no activities on the bacteria. Compound 1 should be considered as a new lead or model compound to develop new isocoumarin antimicrobial agents.
p. 14099-14110
Received: 25 September 2012; in revised form: 19 November 2012 / Accepted: 23 November 2012 / Published: 28 November 2012
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| Download PDF Full-text (282 KB) | Download XML Full-text | Abstract: An efficient method for the allylation of aldehydes containing a broad range of functional groups using potassium allyltrifluoroborate is described. The reaction utilizes a catalytic amount of 18-C -6 in biphasic media under open atmosphere and room temperature to provide the corresponding homoallylic alcohols in high yields and without the necessity of any subsequent purification.
p. 14111-14125
Received: 8 October 2012; in revised form: 11 November 2012 / Accepted: 14 November 2012 / Published: 28 November 2012
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| Download PDF Full-text (227 KB) Abstract: A combined approach of subwindow factor analysis and spectral correlative chromatography was used to analyze the volatile components in Radix Flemingiae Macrophyllae and Flemingiae Latifolia Benth, one of its substitutes. After extraction by a water distillation method, the volatile components in Radix Flemingiae Macrophyllae and Flemingiae Latifolia Benth were detected by GC-MS. Then the qualitative and quantitative analysis of the volatile components in Radix Flemingiae Macrophyllae was completed with the help of subwindow factor analysis resolving two-dimensional original data into mass spectra and chromatograms. Sixty five of 82 separated constituents in the total ion chromatogram of the volatile components in Radix Flemingiae Macrophyllae were identified and quantified, accounting for about 88.79% of the total content. Then, spectral correlative chromatography was used to extract correlative constituents in Flemingiae Latifolia Benth. Fifty one correlative components were recognized in essential oil of Flemingiae Latifolia Benth. The result proves the combined approach is powerful in the analysis of complex herbal samples. The developed method can be used to compare the sameness and differences of Radix Flemingiae Macrophyllae and its substitutes and it can also be used for quality control of Radix Flemingiae Macrophyllae.
p. 14126-14145
Received: 6 November 2012; in revised form: 19 November 2012 / Accepted: 20 November 2012 / Published: 28 November 2012
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| Download PDF Full-text (453 KB) | Abstract: In this paper we report the design, synthesis, antinociceptive and anti-inflammatory activities of a series of benzothiazine N -acylhydrazones 14a –h , planned by structural modification of piroxicam (1 ), a non steroidal anti-inflammatory drug. Among the synthesized analogues, compounds 14f (LASSBio-1637) and 14g (LASSBio-1639) were identified as novel antinociceptive and anti-inflammatory prototypes, active by oral administration, acting by a mechanism of action that seems to be different from that of piroxicam, since they were inactive as an inhibitor of cyclooxygenase (COX-1 and COX-2) at concentrations of 10 mM.
p. 14146-14158
Received: 23 October 2012; in revised form: 12 November 2012 / Accepted: 23 November 2012 / Published: 28 November 2012
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| Download PDF Full-text (287 KB) | Download XML Full-text | Abstract: An efficient and convenient approach for one-pot synthesis of 3-substituted chroman-2,4-diones via a three-component reaction of aromatic aldehydes, 4-hydroxy- coumarins and diverse pyrazolone derivatives was described. The combinatorial synthesis for this methodology was achieved by applying ultrasound irradiation in the absence of activator while making use of water as green solvent. Additionally, novel chroman-2,4-dione derivatives attached to an edaravone moiety represent an exploitable source of brand new anticancer agents. In comparison with conventional methods, experimental simplicity, good functional group tolerance, excellent yields, short routine, and atom efficiency are prominent features of this sonocatalyzed procedure.
p. 14159-14173
Received: 22 October 2012; in revised form: 21 November 2012 / Accepted: 26 November 2012 / Published: 28 November 2012
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| Download PDF Full-text (517 KB) | Download XML Full-text Abstract: Pyrene derivatives can be carcinogenic, teratogenic and mutagenic, thus having the potential to cause malignant diseases. In this work, the interactions of two selected pyrene derivatives (1-OHP and 1-PBO) and human tumor-related DNA (p53 DNA and C-myc DNA) are investigated by spectroscopic and non-native polyacrylamide gel electrophoresis (PAGE) methods. Using fluorescence spectrometry and circular dichroism (CD), DNA interactions of pyrene derivatives are confirmed to occur mainly via the groove binding mode supported by the intercalation into the base pairs of DNA. There is an obvious binding order of pyrene derivatives to the targeted DNA, 1-OHP > 1-PBO. The binding constants of 1-OHP are 1.16 × 106 L×mol−1 and 4.04 × 105 L×mol−1 for p53 DNA and C-myc DNA, respectively, while that of 1-PBO are only 2.04 × 103 L×mol−1 and 1.39 × 103 L×mol−1 for p53 DNA and C-myc DNA, respectively. Besides, the binding of pyrene derivatives to p53 DNA is stronger than that for C-myc DNA. CD and PAGE results indicate that the binding of pyrene derivatives can affect the helical structures of DNA and further induce the formation of double-chain antiparallel G-quadruplex DNA of hybrid G-rich sequences.
p. 14174-14185
Received: 1 November 2012; in revised form: 19 November 2012 / Accepted: 23 November 2012 / Published: 30 November 2012
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| Download PDF Full-text (354 KB) | Download XML Full-text | Abstract: Biotin is an important molecule for modern biological studies including, e.g., cellular transport. Its exclusive affinity to fluorescent streptavidin/avidin proteins allows ready and specific detection. As a consequence methods for the attachment of biotin to various biological targets are of high importance, especially when they are very selective and can also proceed in water. One useful method is Hüisgen dipolar [3+2]-cycloaddition, commonly referred to as “click chemistry”. As we reported recently, the activated triple bond donor p -(N -propynoylamino)toluic acid (PATA) gives excellent results when used for conjugations at submicromolar concentrations. Thus, we have designed and synthesized two biotin linkers, with different lengths equipped with this activated triple bond donor and we proceeded with biotinylation of oligonucleotides and C-myc peptide both in solution and on solid support with excellent yields of conversion.
p. 14186-14204
Received: 8 November 2012; in revised form: 20 November 2012 / Accepted: 23 November 2012 / Published: 30 November 2012
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| Download PDF Full-text (1192 KB) Abstract: Iodine-methanol mediated oxidative-aromatization of 2-aryl-6,8-dibromo-2,3-dihydroquinolin-4(1H )-ones afforded the corresponding 2-aryl-6,8-dibromo-4-methoxy-quinolines in high yield and purity. The isomeric 1-(2-amino-3,5-dibromophenyl)-3-aryl-2-propen-1-ones reacted with iodine in methanol afford in a single pot operation the corresponding 2-aryl-6,8-dibromo-4-methoxyquinoline (major) and 2-aryl-6,8-dibromoquinolin-4(1H )-one (minor) products that were separated in sequence by column chromatography on silica gel. Suzuki-Miyaura cross-coupling of the 6,8-dibromo-4-methoxyquinoline derivatives with excess arylvinylboronic acids afforded the corresponding 2-aryl-6,8-bis(2-arylethenyl)-4-methoxyquinolines. The absorption and fluorescence properties of these compounds were also determined.
p. 14205-14218
Received: 18 October 2012; in revised form: 26 November 2012 / Accepted: 27 November 2012 / Published: 30 November 2012
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| Download PDF Full-text (317 KB) Abstract: A series of N -(substituted pyridinyl)-1-methyl(phenyl)-3-trifluoromethyl-1H -pyrazole-4-carboxamide derivatives were synthesized. All target compounds were characterized by spectral data (1 H-NMR, 13 C-NMR, IR, MS) and elemental analysis and were bioassayed in vitro against three kinds of phytopathogenic fungi (Gibberella zeae , Fusarium oxysporum , Cytospora mandshurica ). The results showed that some of the synthesized N -(substituted pyridinyl)-1-methyl-3-trifluoromethyl-1H -pyrazole-4-carboxamides exhibited moderate antifungal activities, among which compounds 6a , 6b and 6c displayed more than 50% inhibition activities against G. zeae at 100 µg/mL, which was better than that of the commercial fungicides carboxin and boscalid.
p. 14219-14229
Received: 10 October 2012; in revised form: 24 November 2012 / Accepted: 27 November 2012 / Published: 30 November 2012
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| Download PDF Full-text (251 KB) | Download XML Full-text Abstract: Azo dyes are generally resistant to biodegradation due to their complex structures. Acid orange II is one of the most widely used dyes in the textile industry. The influence of bovine serum albumin (BSA) in different concentrations, pH, and time of contact on Orange II was investigated using kinetics and adsorption-isotherm experiments. The results showed that the maximum colour removed from dye/albumin was 99.50% and that a stable dye-protein complex had been formed at pH 3.5 and in a proportion of 1:3 (v/v), respectively. The synthetic effluent did not show toxicity to the microcrustacean Artemia salina , and showed a CL50 equal to 97 µg/mL to azo dye orange II. Additionally, the methodology was effective in removing the maximum of orange II using BSA by adsorption at pH 3.5 which mainly attracted ions to the azo dye during the adsorption process. This suggests that this form of treatment is economical and easy to use which potentially could lead to bovine serum albumin being used as a sorbent for azo dyes.
p. 14230-14248
Received: 8 October 2012; in revised form: 20 November 2012 / Accepted: 28 November 2012 / Published: 30 November 2012
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| Download PDF Full-text (768 KB) | Download XML Full-text Abstract: The matrix metalloproteinases (MMPs) exhibit a broad array of activities, some catalytic and some non-catalytic in nature. An overall lack of selectivity has rendered small molecule, active site targeted MMP inhibitors problematic in execution. Inhibitors that favor few or individual members of the MMP family often take advantage of interactions outside the enzyme active site. We presently focus on peptide-based MMP inhibitors and probes that do not incorporate conventional Zn2+ binding groups. In some cases, these inhibitors and probes function by binding only secondary binding sites (exosites), while others bind both exosites and the active site. A myriad of MMP mediated-activities beyond selective catalysis can be inhibited by peptides, particularly cell adhesion, proliferation, motility, and invasion. Selective MMP binding peptides comprise highly customizable, unique imaging agents. Areas of needed improvement for MMP targeting peptides include binding affinity and stability.
p. 14249-14259
Received: 8 November 2012; in revised form: 21 November 2012 / Accepted: 27 November 2012 / Published: 30 November 2012
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| Download PDF Full-text (378 KB) | Download XML Full-text Abstract: The rearrangement of allyl a-bromoacetates with Zn dust is known as the Reformatsky-Claisen rearrangement. Whereas the Ireland-Claisen rearrangement has been widely used in the synthesis of a diverse range of natural products, the Zn-mediated Reformatsky-Claisen rearrangement has not been utilized so often. In this article, we will provide an overview of recent advances in the Reformatsky-Claisen rearrangement field, including the In-mediated Reformatsky-Claisen rearrangement we have recently developed.
p. 14260-14274
Received: 8 October 2012; in revised form: 13 November 2012 / Accepted: 26 November 2012 / Published: 30 November 2012
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| Download PDF Full-text (244 KB) Abstract: Bioflocculant-producing bacteria were isolated from activated sludge of a wastewater treatment plant located in Durban, South Africa, and identified using standard biochemical tests as well as the analysis of their 16S rRNA gene sequences. The bioflocculants produced by these organisms were ethanol precipitated, purified using 2% (w/v) cetylpyridinium chloride solution and evaluated for removal of wastewater dyes under different pH, temperature and nutritional conditions. Bioflocculants from these indigenous bacteria were very effective for decolourizing the different dyes tested in this study, with a removal rate of up to 97.04%. The decolourization efficiency was largely influenced by the type of dye, pH, temperature, and flocculant concentration. A pH of 7 was found to be optimum for the removal of both whale and mediblue dyes, while the optimum pH for fawn and mixed dye removal was found to be between 9 and 10. Optimum temperature for whale and mediblue dye removal was 35 °C, and that for fawn and mixed dye varied between 40–45 °C and 35–40 °C, respectively. These bacterial bioflocculants may provide an economical and cleaner alternative to replace or supplement present treatment processes for the removal of dyes from wastewater effluents, since they are biodegradable and easily sustainable.
p. 14275-14287
Received: 15 June 2012; in revised form: 18 October 2012 / Accepted: 29 October 2012 / Published: 3 December 2012
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| Download PDF Full-text (573 KB) | Abstract: The antimicrobial, antioxidant and cytotoxic properties of Mazus goodenifolius (Hornem.) Pennell essential oil, methanol extract and some solvent-extracted subfractions of the latter were appraised. A qualitative, quantitative analysis of the classes of phytochemicals in the various fractions and GC-MS analysis of the essential oil was carried out. The activity of the plant extract and various subfractions against selected bacterial (Pasturella multocida , Escherichia coli , Bacillus subtilis and Staphylococcus aureus ) and fungal strains (Aspergillus niger , Aspergillus flavus , Alternaria alternata and Rhizopus solani ) was evaluated. The antioxidant activity was assayed using the DPPH radical scavenging and % inhibition of linoleic acid peroxidation tests. In the DPPH radical scavenging test the IC50 values ranged from 7.21 to 91.79 µg/mL, and in the latter the range of % peroxidation inhibition was 35.42–93.48%. Protective effects of the absolute methanol extract, which had the highest content of phenolics and flavonoids, against H2 O2 induced oxidative damage in plasmid pBR322 DNA was also evaluated, and it was found to offer some protection at the highest tested dose (1,000 µg/mL). Finally the cytotoxicity of the plant extract, fractions and essential oil was analyzed by examining haemolytic activity against human blood erythrocytes (RBCs), whereby the % lysis of RBCs was found to be in the range of 1.65 to 4.01%.
p. 14288-14297
Received: 6 November 2012; in revised form: 27 November 2012 / Accepted: 28 November 2012 / Published: 3 December 2012
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| Download PDF Full-text (244 KB) | Abstract: A facile synthesis for novel loperamide analogs as potential μ opioid receptors is described. The synthetic procedure for compound 5 , which contains two 4-phenyl piperidine scaffolds, was optimized, and this compound was synthesized in excellent yield. We also describe a mild and highly efficient protocol for the synthesis of compounds 6 and 7 .
p. 14298-14309
Received: 29 September 2012; in revised form: 19 November 2012 / Accepted: 20 November 2012 / Published: 3 December 2012
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| Download PDF Full-text (646 KB) Abstract: Studies evaluating the toxicity caused by fungal exopolysaccharides of the β-(1→6)-D-glucan type are rare. In this study, the toxicological effects of sub-chronic treatments with lasiodiplodan (β-(1→6)-D-glucan from Lasiodiplodia theobromae MMPI) were evaluated in mice through the assessment of biochemical, hematological, and histopathological alterations. Thirty-two mice (16 male, 16 female) were used in this study divided in two groups; one group received lasiodiplodan (50 mg/kg body weight) daily for 28 days via gavage, and another (control group) received saline during the same period. Blood samples were collected via cardiac puncture for hematological and biochemical analyses. Liver, heart, kidney, and spleen were collected for histopathological analysis. Statistical analysis was performed through one-way analysis of variance and only p < 0.05 F-values were presented. Significant reduction in blood glucose in the male group (35%; p < 0.01), transaminases activity in both sexes (AST and ALT; ~35%; p < 0.05), and urea (20%; p < 0.01) in the female group was observed with the lasiodiplodan treatment. The results showed that sub-chronic treatments with lasiodiplodan did not generate hematological and histopathological alterations leading to signs of toxicity in healthy mice, independent of gender.
p. 14310-14322
Received: 13 September 2012; in revised form: 27 November 2012 / Accepted: 28 November 2012 / Published: 3 December 2012
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| Download PDF Full-text (274 KB) Abstract: The phytochemical investigation of the n -hexane extract from callus and cell suspension culture of Arnebia euchroma (Royle) Jonst. resulted in the isolation of nine isohexenylnaphthazarins: deoxyalkannin (1 ), alkannin (2 ), acetylalkannin (3 ), isobutyrylalkannin (4 ), β- hydroxyisovalerylalkannin (5 ), 2''-(S )-α-methylbutyrylalkannin (6 ), propionylalkannin (7 ), teracrylalkannin (8 ) and acetylshikonin (9 ). Their structures were determined by MS and NMR spectroscopy. Pigments 2 –8 are isolated for the first time from Arnebia in vitro cultures, 4 and 7 are reported in the present work as novel metabolites within the Arnebia genus, while 9 is a known constituent of both natural roots and in vitro cultures of A. euchroma. Moreover, methyl jasmonate and 1-monoglyceryl olate, palmitate and stearate are reported for the first time within the Boraginaceae family. The antimicrobial and cytotoxic activities of all isolated pigment compounds were tested, revealing a very interesting profile.
p. 14323-14335
Received: 31 October 2012; in revised form: 20 November 2012 / Accepted: 24 November 2012 / Published: 3 December 2012
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| Download PDF Full-text (666 KB) | Download XML Full-text Abstract: An ionic liquids (IL)-based microwave-assisted approach for extraction and determination of flavonoids from Bauhinia championii (Benth.) Benth . was proposed for the first time. Several ILs with different cations and anions and the microwave-assisted extraction (MAE) conditions, including sample particle size, extraction time and liquid-solid ratio, were investigated. Two M 1-butyl-3-methylimidazolium bromide ([bmim] Br) solution with 0.80 M HCl was selected as the optimal solvent. Meanwhile the optimized conditions a ratio of liquid to material of 30:1, and the extraction for 10 min at 70 °C. Compared with conventional heat-reflux extraction (CHRE) and the regular MAE, IL-MAE exhibited a higher extraction yield and shorter extraction time (from 1.5 h to 10 min). The optimized extraction samples were analysed by LC-MS/MS. IL extracts of Bauhinia championii (Benth.) Benth consisted mainly of flavonoids, among which myricetin, quercetin and kaempferol, β-sitosterol, triacontane and hexacontane were identified. The study indicated that IL-MAE was an efficient and rapid method with simple sample preparation. LC-MS/MS was also used to determine the chemical composition of the ethyl acetate/MAE extract of Bauhinia championii (Benth.) Benth , and it maybe become a rapid method to determine the composition of new plant extracts.
p. 14336-14348
Received: 21 September 2012; in revised form: 7 November 2012 / Accepted: 13 November 2012 / Published: 3 December 2012
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| Download PDF Full-text (276 KB) Abstract: The well-known antioxidant activity of red wine is explained mostly by its polyphenols content, where the final effect is based on the wine components’ interaction. The aim of our work was the study of the interaction of three red wine polyphenols—quercetin, resveratrol and caffeic acid—alone and in their equimolar binary and ternary mixtures in different antioxidant/scavenging assays (inhibition of 2-deoxy-D-ribose degradation by hydroxyl radical, FRAP, Fe(III) reducing power, DPPH, ABTS and NO scavenging, respectively). Interaction analysis, based on median effect equation, was performed for the determination of synergy and/or antagonism. The obtained results indicate that the mutual interactions of tested polyphenols in their mixtures are markedly different from each other, depending on the reaction mechanism of the assay used. The measured antioxidant activity of individual polyphenols is not a constant value when other substances are present in the mixture with this polyphenol. Interactions can cause the finally observed synergy/antagonism/additive effects without any possibility of predicting them from the known activities of single compounds. This “unpredictability” claim based on in vitro assay results should be very important in multiple systems and processes in Nature, where the interactions among compounds in mixtures need to be take into account.
p. 14349-14360
Received: 15 October 2012; in revised form: 18 November 2012 / Accepted: 30 November 2012 / Published: 3 December 2012
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| Download PDF Full-text (191 KB) | Download XML Full-text Abstract: Malaria, leishmaniasis and human African trypanosomiasis continue to be major public health problems in need of new and more effective drugs. The aim of this study was to evaluate in vitro antiprotozoal activity of twenty endemic medicinal plants collected from the island of Soqotra in the Indian Ocean. The plant materials were extracted with methanol and tested for antiplasmodial activity against erythrocytic schizonts of Plasmodium falciparum , for antileishmanial activity against intracellular amastigotes of Leishmania infantum and for antitrypanosomal activity against intracellular amastigotes of Trypanosoma cruzi and free trypomastigotes of T. brucei . To assess selectivity, cytotoxicity was determined against MRC-5 fibroblasts. Selective activity was obtained for Punica protopunica against Plasmodium (IC50 2.2 µg/mL) while Eureiandra balfourii and Hypoestes pubescens displayed activity against the three kinetoplastid parasites (IC50 < 10 µg/mL). Acridocarpus socotranus showed activity against T. brucei and T. cruzi (IC50 3.5 and 8.4 µg/mL). Ballochia atrovirgata , Dendrosicycos socotrana , Dracaena cinnabari and Euphorbia socotrana displayed non-specific inhibition of the parasites related to high cytotoxicity.
p. 14361-14376
Received: 22 October 2012; in revised form: 23 November 2012 / Accepted: 30 November 2012 / Published: 5 December 2012
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| Download PDF Full-text (333 KB) Abstract: We have demonstrated that oxime-based mixed carbonates are very effective reagents for both N- protection and peptide coupling.
p. 14377-14392
Received: 16 November 2012; in revised form: 29 November 2012 / Accepted: 29 November 2012 / Published: 5 December 2012
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| Download PDF Full-text (369 KB) Abstract: Five sulfonyl aromatic alcohols, namely 4-((2-hydroxyethyl)sulfonyl)phenol, 4-((2-(2-((4-hydroxyphenyl)sulfonyl)ethoxy)vinyl)sulfonyl)phenol, 4-(ethylsulfonyl)phenol, 4-(vinylsulfonyl)phenol and 5-((4-aminophenyl)sulfonyl)-2-penten-1-ol were identified by LC-ESI-Qq-TOF-MS as products formed by electrolysis of the bisazo reactive dye Reactive Black 5 (RB5). Since electrolyses were performed in an undivided cell equipped with Ni electrodes in alkaline medium, amines like 4-(2-methoxyethylsulfonyl)benzene-amine (MEBA) with m/z 216 were also suspected to be formed due to the plausible chemical reaction in the bulk or the cathodic reduction of RB5 and its oxidation by-products. Aiming to check this hypothesis, a method was used for the preparation of MEBA with 98% purity, via chemical reduction also of the dye RB5. The logP of the synthesized sulfonyl aromatic compounds was calculated and their logkw values were determined chromatographically. These data were discussed in regard to the relationship between hydrophobicity/lipophilicity and toxicity.
p. 14393-14408
Received: 25 October 2012; in revised form: 30 November 2012 / Accepted: 3 December 2012 / Published: 5 December 2012
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| Download PDF Full-text (821 KB) Abstract: The application of the exopolysaccharide-producing strains for improving the texture and technical properties of reduced-fat cheese looks very promising. Streptococcus thermophilus TM11 was evaluated for production of reduced-fat cheese using reconstituted milk powder (CRMP). The physicochemical analysis of fresh and stored cheeses showed that this strain slightly increased moisture content resulting in cheese with higher yield and lower protein content compared to the direct acidified cheese. The volatiles of cheese were determined by SPME and GC equipped with a mass spectrometer. The results indicated that the major compounds included aldehydes, ketones and acids, whereas, alcohols and branched-chain aldehydes that contribute to exciting and harsh flavors were not found in CRMP. By the textural profile analysis, we found the cheese made with S. thermophilus TM11 had lower cohesiveness, resilience and higher adhesiveness than the direct acidified cheese, and had similar hardness. Further, S. thermophilus TM11 greatly changed the protein matrix with more opened cavities according to observation by scanning electron microscopy. Consequently, use of S. thermophilus TM11 could endow CRMP with the novel and suitable flavor properties and improved texture quality.
p. 14409-14417
Received: 8 October 2012; in revised form: 20 November 2012 / Accepted: 23 November 2012 / Published: 5 December 2012
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| Download PDF Full-text (223 KB) Abstract: Following our previous results on an environmentally benign one-pot Sonogashira- cyclization protocol to obtain substituted furopyrimidine nucleosides under aqueous conditions, we investigate herein the Suzuki-Miyaura cross-coupling reactions of aryl and heteroaryl derivatives at the C5 position of unprotected 2'-deoxyuridine in the same media with a common catalyst system avoiding exotic ligands, since palladium acetate and triphenylphosphine afforded the expected products in moderate to good yields.
p. 14418-14433
Received: 19 October 2012; in revised form: 31 October 2012 / Accepted: 20 November 2012 / Published: 5 December 2012
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| Download PDF Full-text (236 KB) Abstract: Mucormycoses are emerging infections that have high rates of morbidity and mortality. They show high resistance to antifungal agents, and there is a limited therapeutic arsenal currently available, therefore, there is a great need to give priority to testing therapeutic agents for the treatment of mucormycosis. Along this line, the use of essential oils and phytoconstituents has been emphasized as a new therapeutic approach. The objective of this work was to investigate the antifungal activity of the essential oil (EO) of Thymus vulgaris , and its constituents thymol and p -cymene against Rhizopus oryzae , through microbiological screening, determination of minimal inhibitory concentration (MICs) and minimal fungicidal concentration (MFCs), effects on mycelial growth and germination of sporangiospores and interaction with ergosterol. The MIC of EO and thymol varied 128–512 µg/mL, but the MFC of EO and thymol varied 512–1024 µg/mL and 128–1024 µg/mL, respectively. The results also showed that EO and thymol significantly inhibited mycelial development and germination of sporangiospores. Investigation of the mechanism of antifungal action showed that EO and thymol interact with ergosterol. These data indicate that EO of T. vulgari s and thymol possess strong antifungal activity, which can be related to their interaction with ergosterol, supporting the possible use of these products in the treatment of mucormycosis.
p. 14434-14448
Received: 9 October 2012; in revised form: 26 November 2012 / Accepted: 3 December 2012 / Published: 5 December 2012
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| Download PDF Full-text (251 KB) | Download XML Full-text Abstract: New 3-substituted 1-(3-hydroxyphenyl)-5-oxopyrrolidine derivatives containing hydrazone, azole, diazole, oxadiazole fragments, as well as 2-phenoxy- and 2,3-diphenoxy-1,4-naphthoquinone derivatives were synthesized. The structure of all compounds has been confirmed by NMR, IR, mass spectra, and elemental analysis data. Methyl 1-{3-[(3-chloro-1,4-dioxo-1,4-dihydro-2-naphthalenyl)oxy]phenyl}-5-oxo-3-pyrrolidinecarboxylate demonstrated potential antibacterial and antifungal activities as determined by diffusion and serial dilution methods, while N '-[(4-bromophenyl)methylidene]-1-{3-[(3-chloro-1,4-dioxo-1,4-dihydro-2-naphthalenyl)oxy]phenyl}-5-oxo-3-pyrrolidinecarbohydrazide and 2-{3-[4-(1,2,3-oxadiazol-5-yl)-2-oxo-1-pyrrolidinyl]phenoxy}-3-{3-[4-(1,3,4-oxadiazol-2-yl)-2-oxo- 1-pyrrolidinyl]phenoxy}naphthoquinone showed antifungal activity against Candida tenuis and Aspergillus niger at low concentrations, as determined by the serial dilution method. The substitution of the methoxy fragment by N- containing substituents in monophenoxy substituted naphthoquinones was found to decrease their activity against Mycobacterium luteum . Besides, introduction of the second phenoxy substituted fragment increased the antifungal activity against Candida tenuis and Aspergillus niger at lower concentrations.
p. 14449-14463
Received: 8 October 2012; in revised form: 6 November 2012 / Accepted: 13 November 2012 / Published: 5 December 2012
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| Download PDF Full-text (1003 KB) | Download XML Full-text Abstract: The traditional use of Murraya koenigii as Asian folk medicine prompted us to investigate its wound healing ability. Three carbazole alkaloids (mahanine (1 ), mahanimbicine (2 ), mahanimbine (3 )), essential oil and ethanol extract of Murraya koenigii were investigated for their efficacy in healing subcutaneous wounds. Topical application of the three alkaloids, essential oil and crude extract on 8 mm wounds created on the dorsal skin of rats was monitored for 18 days. Wound contraction rate and epithelialization duration were calculated, while wound granulation and collagen deposition were evaluated via histological method. Wound contraction rates were obvious by day 4 for the group treated with extract (19.25%) and the group treated with mahanimbicine (2 ) (12.60%), while complete epithelialization was achieved on day 18 for all treatment groups. Wounds treated with mahanimbicine (2 ) (88.54%) and extract of M. koenigii (91.78%) showed the highest rate of collagen deposition with well-organized collagen bands, formation of fibroblasts, hair follicle buds and with reduced inflammatory cells compared to wounds treated with mahanine (1 ), mahanimbine (3 ) and essential oil. The study revealed the potential of mahanimbicine (2 ) and crude extract of M. koenigii in facilitation and acceleration of wound healing.
p. 14464-14483
Received: 24 October 2012; in revised form: 25 November 2012 / Accepted: 27 November 2012 / Published: 6 December 2012
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| Download PDF Full-text (294 KB) | Abstract: The synthesis of 3-methyl-1,4-diphenyl-7-thioxo-4,6,8,9-tetrahydropyrazolo[5,4-b ] pyrimidino[5,4-e ]pyridine-5-one (6) was achieved by two different one-pot multi-component synthesis (one-pot three-component and one-pot four component synthesis). Mono and dialkylation of 6 under different conditions gave compounds 7 –11 . The hydrazine 12 produced from reaction of 9 with N2 H4 was subjected to reactions with some aromatic aldehydes, ethyl acetoacetate, acetyl acetone, ethyl cyanoacetate and triethyl orthoformate to give 13 –17 , respectively. Compound 12 upon reaction with CS2 , nitrous acid, benzoin, chloroacetone and phenacyl bromide gave 18 ,20 ,21 ,22 . Alkylation of 18 with ethyl iodide, ethyl chloroacetate and phenacyl bromide gave 19a –c . The antibacterial and antifungal activities of selected derivatives were evaluated.
p. 14484-14489
Received: 9 October 2012; in revised form: 14 November 2012 / Accepted: 26 November 2012 / Published: 6 December 2012
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| Download PDF Full-text (827 KB) Abstract: Dispersed particle gel (DPG) has been first successfully prepared using cross-linked gel systems through a simple high speed shearing method with the aid of a colloid mill at room temperature. The gel microstructure and particle size were investigated by scanning electron microscope (SEM), transmission electron microscope (TEM), and dynamic light scattering (DLS) measurements. The results clearly show that the prepared DPG particles have highly uniformly spherical structures with an average size of 2.5 μm. A possible mechanism for the formation of DPG has been put forward and discussed in details. The high speed shearing method is considered to be the simple and rapid method for the preparation of DPG.
p. 14490-14509
Received: 27 September 2012; in revised form: 26 November 2012 / Accepted: 29 November 2012 / Published: 6 December 2012
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| Download PDF Full-text (236 KB) Abstract: Chinese hawthorn (Crataegus pinnatifida Bge.) fruits are rich in polyphenols (e.g., epicatechin, procyanidin B2, procyanidin B5, procyanidin C1, hyperoside, isoquercitrin and chlorogenic acid)—active compounds that exert beneficial effects. This review summarizes all information available on polyphenolic content and methods for their quantification in Chinese hawthorn berries and the relationships between individual polyphenolic compounds as well. The influence of species or cultivars, the locality of cultivation, the stage of maturity, and extract preparation conditions on the polyphenolic content were discussed as well. Currently, only fruits of C. pinnatifida and C. pinnatifida var. major are included in the Chinese Pharmacopoeia. Recent trials have demonstrated the efficacy of Chinese hawthorn fruit in lowering blood cholesterol and the risk of cardiovascular diseases. The fruit has also demonstrated anti-inflammatory and anti-tumour activities. This review deals mainly with the biological activity of the fruit related to its antioxidant properties.
p. 14510-14521
Received: 17 September 2012; in revised form: 26 November 2012 / Accepted: 28 November 2012 / Published: 6 December 2012
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| Download PDF Full-text (198 KB) Abstract: A series of macrocyclic imides and Schiff-bases have been prepared via the cyclocondensation of pyridine-2,6-dicarbonyl dichloride (1 ) with L-ornithine methyl ester to give the corresponding macrocyclic bisester 2 . Treatment of 2 with hydrazine hydrate gave macrocyclic bisacid hydrazide 3 , which was used as starting material. Condensation of bishydrazide 3 with diacid anhydrides or aromatic aldehydes in refluxing acetic acid or ethanol gave the corresponding macrocyclic bisimides 4 , 5a ,b and macrocyclic bis- hydrazones 6a –j , respectively. The structure assignments of the new compounds were based on chemical and spectroscopic evidence. The antimicrobial screening showed that many of these newly synthesized compounds have good antimicrobial activities, comparable to ampicillin and ketaconazole used as reference drugs.
p. 14522-14530
Received: 1 November 2012; in revised form: 28 November 2012 / Accepted: 30 November 2012 / Published: 7 December 2012
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| Download PDF Full-text (299 KB) Abstract: In order to study the effect of heterocyclic core conformational state of leucamide A on its anti-influenza virus A activity, five conformational analogues were prepared by replacing the Pro-Leu dipeptide in the molecule with various amino acids. The amino acids used were of 2 to 6 carbons. The results showed that these replacements not only changed the conformational relationship between the 4,2-bisheterocycle tandem pair and the third heterocycle, but also had dramatic effect on its activity against influenza virus A.
p. 14531-14554
Received: 30 October 2012; in revised form: 29 November 2012 / Accepted: 3 December 2012 / Published: 7 December 2012
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| Download PDF Full-text (546 KB) | Abstract: Attempted RCM of 2,2'-bis(allyloxy)-1,1'-binaphthyl resulted in a Claisen-type rearrangement of a postulated labile dioxacyclodecine proceeding at room temperature and followed by [2+2] cycloaddition. Structures of products were confirmed by X-ray crystallography. A mechanistic rationalisation based on relative stabilities of proposed intermediates and transition states is provided.
p. 14555-14564
Received: 10 October 2012; in revised form: 6 December 2012 / Accepted: 7 December 2012 / Published: 7 December 2012
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| Download PDF Full-text (340 KB) Abstract: A sensitive and accurate high performance liquid chromatography with ultraviolet/visible light detection (HPLC-UV/VIS) method for the quantification of 2,6-bis-(4-hydroxy-3-methoxybenzylidene)-cyclohexanone (BHMC) in rat plasma was developed and validated. BHMC and the internal standard, harmaline, were extracted from plasma samples by a simple liquid–liquid extraction using 95% ethyl acetate and 5% methanol. Plasma concentration of BHMC and internal standard were analyzed by reversed phase chromatography using a C18 column (150 × 4.6 mm I.D., particle size 5 µm) and elution with a gradient mobile phase of water and methanol at a flow rate of 1.0 mL/min. Detection of BHMC and internal standard was done at a wavelength of 380 nm. The limit of quantification was 0.02 µg/mL. The calibration curves was linear (R2 > 0.999) over the concentration range of 0.02–2.5 µg/mL. Intra- and inter-day precision were less than 2% coefficient of variation. The validated method was then applied to a pharmacokinetic study in rats by intravenous administration of BHMC at a single dose of 10 mg/kg. Pharmacokinetic parameters such as half-life, maximum plasma concentration, volume of distribution, clearance and elimination rate constant for BHMC were calculated.
p. 14565-14572
Received: 9 November 2012; in revised form: 3 December 2012 / Accepted: 5 December 2012 / Published: 7 December 2012
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| Download PDF Full-text (211 KB) Abstract: Cadmium (Cd) is a heavy metal that poses a hazard to animal health due to its toxicity. Selenium (Se) is an important nutritional trace element. However, the potential protective effects of Se against Cd-induced toxicity remain to be elucidated. To investigate the cytotoxicity of Cd on bird immunocytes in vitro and the protective effects of Se against exposure to Cd, chicken splenic lymphocytes received Cd (10−6 mol/L), Se (10−7 mol/L), and the mixture of 10−7 mol/L Se and 10−6 mol/L Cd and were incubated for 12 h, 24 h, 36 h, 48 h, respectively. The transcription of heat shock protein (HSP) 27, HSP40, HSP60, HSP70 and HSP90 mRNA was tested by fluorescence quantitative PCR. The results showed that the mRNA expression of HSPs exposed to 10−6 mol/L Cd showed a sustained decrease at 12–48 h exposure. A statistically significant increase in the mRNA expression of HSPs in the case of Se group was observed, as compared to the control group of chicken splenic lymphocytes. Concomitantly, treatment of chicken splenic lymphocytes with Se in combination with Cd enhanced the mRNA expression of HSPs which were reduced by Cd treatment. This indicated that the protective effect of Se against the toxicity of Cd might, at least partially, be attributed to stimulation of the level of HSPs.
p. 14573-14587
Received: 23 November 2012; in revised form: 29 November 2012 / Accepted: 5 December 2012 / Published: 7 December 2012
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| Download PDF Full-text (263 KB) Abstract: Alkynylphosphines or their borane complexes are available either through C–P bond forming reactions or through modification of the phosphorus or the alkynyl function of various alkynyl phosphorus derivatives. The latter strategy, and in particular the one involving phosphoryl reduction by alanes or silanes, is the method of choice for preparing primary and secondary alkynylphosphines, while the former strategy is usually employed for the synthesis of tertiary alkynylphosphines or their borane complexes. The classical C–P bond forming methods rely on the reaction between halophosphines or their borane complexes with terminal acetylenes in the presence of a stoichiometric amount of organometallic bases, which precludes the access to alkynylphosphines bearing sensitive functional groups. In less than a decade, efficient catalytic procedures, mostly involving copper complexes and either an electrophilic or a nucleophilic phosphorus reagent, have emerged. By proceeding under mild conditions, these new methods have allowed a significant broadening of the substituent scope and structure complexity.
p. 14588-14601
Received: 9 October 2012; in revised form: 5 November 2012 / Accepted: 28 November 2012 / Published: 7 December 2012
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| Download PDF Full-text (842 KB) Abstract: C80 is a fullerene species which appears in different isomeric configurations. A general homodesmotic reaction previously designed to study the energy of fullerenes was implemented, in order to analyze the energy of this family of isomers. These results concur with some of the experimental data, but energy differences referring to all the configurations yield novel propositions about their particular behavior. The corresponding lanthanum complexes are also analyzed here and a new isodesmic reaction was designed for this particular case.
p. 14602-14624
Received: 16 November 2012; in revised form: 26 November 2012 / Accepted: 5 December 2012 / Published: 7 December 2012
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| Download PDF Full-text (505 KB) Abstract: Cyclopia subternata plants are traditionally used for the production of the South African herbal tea, honeybush, and recently as aqueous extracts for the food industry. A C. subternata aqueous extract and mangiferin (a major constituent) are known to have anti-diabetic properties. Variation in phenolic composition and antioxidant capacity is expected due to cultivation largely from seedlings, having implications for extract standardization and quality control. Aqueous extracts from 64 seedlings of the same age, cultivated under the same environmental conditions, were analyzed for individual compound content, total polyphenol (TP) content and total antioxidant capacity (TAC) in a number of assays. An HPLC method was developed and validated to allow quantification of xanthones (mangiferin, isomangiferin), flavanones (hesperidin, eriocitrin), a flavone (scolymoside), a benzophenone (iriflophenone-3-C -β-glucoside) and dihydrochalcones (phloretin-3',5'-di-C -β-glucoside, 3-hydroxyphloretin-3',5'-di-C -hexoside). Additional compounds were tentatively identified using mass spectrometric detection, with the presence of the 3-hydroxyphloretin-glycoside, an iriflophenone-di-O ,C -hexoside, an eriodictyol-di-C -hexoside and vicenin-2 being demonstrated for the first time. Variability of the individual phenolic compound contents was generally higher than that of the TP content and TAC values. Among the phenolic compounds, scolymoside, hesperidin and iriflophenone-3-C -β-glucoside contents were the most variable. A combination of the measured parameters could be useful in product standardization by providing a basis for specifying minimum levels.
p. 14625-14636
Received: 16 October 2012; in revised form: 23 November 2012 / Accepted: 26 November 2012 / Published: 10 December 2012
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| Download PDF Full-text (199 KB) Abstract: New series of 1,3,4-thiadiazoles have been prepared via reaction of 1,3,4-thiadiazolenaminones 1 with N -phenyl 2-oxopropanehydrazonoyl chloride (2 ) in dioxane in the presence of triethylamine. Also, some new heterocycles incorporating 1,3,4-thiadiazole ring were obtained by reaction of 1,3,4-thiadiazolenaminones 1 with nitrogen-nucleophiles like hydrazine hydrate, 3-amino-1,2,4-triazole and 2-aminobenzimidazole. The structure of the new products was established based on elemental and spectral analysis. The relation between the structure of the products and their activity towards some microorganisms was studied and promising results were obtained.
p. 14637-14650
Received: 25 October 2012; in revised form: 9 November 2012 / Accepted: 5 December 2012 / Published: 10 December 2012
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| Download PDF Full-text (239 KB) Abstract: Caffeic acid phenethyl ester (CAPE) is a bioactive component isolated from propolis. A series of CAPE analogues was synthesized and their antiradical/antioxidant effects analyzed. The effect of the presence of the double bond and of the conjugated system on the antioxidant effect is evaluated with the analogues obtained from 3-(3,4-dihydroxyphenyl) propanoic acid. Those obtained from 2-(3,4-dihydroxyphenyl) acetic acid and 3,4-dihydroxybenzoic acid allow the evaluation of the effect of the presence of two carbons between the carbonyl and aromatic system.
p. 14651-14672
Received: 17 October 2012; in revised form: 19 November 2012 / Accepted: 5 December 2012 / Published: 10 December 2012
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| Download PDF Full-text (908 KB) Abstract: In this paper we report the design, synthesis and pharmacological evaluation of a new series of phenyl sulfonamide derivatives 2a –h and 3 –8 planned by structural modification on the anti-inflammatory prototype LASSBio-468 (1 ). Among the synthesized analogues, the tetrafluorophthalimide LASSBio-1439 (2e ) stands out showing an in vitro anti-TNF-α effect similar to the standard thalidomide. The relevance of tetrafluorination of the phthalimide nucleus was also confirmed by the anti-inflammatory profile of 2e , through oral administration, in a murine model of pulmonary inflammation. The corresponding tetrafluorocarboxyamide metabolite LASSBio-1454 (15 ), generated from partial hydrolysis of the derivative 2e , presented a significant in vitro effect and a pronounced anti-inflammatory activity in vivo .
p. 14673-14684
Received: 8 October 2012; in revised form: 6 December 2012 / Accepted: 7 December 2012 / Published: 11 December 2012
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| Download PDF Full-text (296 KB) Abstract: Wu-Chia-Pi medicated wine, composed nine Chinese medicines soaked in 35% alcohol, is widely used in Asia for its health-promoting functions. However, long-term consumption of alcohol could result in liver dysfunction. In this study, Wu-Chia-Pi solution (WCPS) and extract (WCPE) were prepared by modification of the principals given by the Committee on Chinese Medicine and Pharmacy in Taiwan. The aim of this study was to explore the protective effect of WCPS against carbon tetrachloride (CCl4 )-induced liver injury and to clarify its active component(s). Antioxidative effects of the test samples were evaluated via MDA inhibition, catalase activity and DPPH-scavenging assays. HPLC was used to analysis the active components. Results showed that WCPS (1 and 5 mL/kg) significantly prevented CCl4 -induced liver injury without chronic liver toxicity. Referring to the antioxidative activities, WCPE displayed significant MDA inhibitory and DPPH-scavenging activities with IC50 values of 0.91 ± 0.03 and 0.60 ± 0.04 mg/mL, respectively. Catalase activity was also enhanced by treatment of WCPE, acteoside and quercetin. Therefore, we suggest that acteoside and quercetin are the major contributors to the antioxidative and hepatoprotective activities of WCPS, and a possible mechanism could be mediated through reduction of oxidative stress.
p. 14685-14699
Received: 21 November 2012; in revised form: 1 December 2012 / Accepted: 6 December 2012 / Published: 11 December 2012
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| Download PDF Full-text (333 KB) | Abstract: The well-known Ugi reaction of aldehydes with amines, carboxylic acids and isocyanides leads to the formation of acyclic α-acylaminocarboxamides. Replacement of the carboxylic acid derivatives with β-acyl substituted acrylic acids gives access to highly substituted 2,5-diketopiperazines in one single reaction-step without additives or complex reaction procedures. The obtained diketopiperazines show anti-proliferative effects on activated T cells and represent therefore potential candidates for targeting unwanted T cell-mediated immune responses.
p. 14700-14732
Received: 31 October 2012; in revised form: 28 November 2012 / Accepted: 6 December 2012 / Published: 11 December 2012
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| Download PDF Full-text (781 KB) Abstract: Titanium complexes have been widely used as catalysts for C‑C bond-forming processes via free-radical routes. Herein we provide an overview of some of the most significant contributions in the field, that covers the last decade, emphasizing the key role played by titanium salts in the promotion of selective reactions aimed at the synthesis of multifunctional organic compounds, including nucleophilic radical additions to imines, pinacol and coupling reactions, ring opening of epoxides and living polymerization.
p. 14733-14747
Received: 20 November 2012; in revised form: 3 December 2012 / Accepted: 6 December 2012 / Published: 11 December 2012
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| Download PDF Full-text (652 KB) Abstract: MicroRNA (miRNA) actively participates in a broad range of cellular processes such as proliferation, differentiation, cell survival and apoptosis. Deregulated expression of miRNA may affect cell growth and eventually lead to cancer. In this study, we found that hsa-miR491-5p (miR491-5p) displays a significantly high level of expression in normal human pancreas tissue versus pancreatic cancer cells. Targeted site prediction indicated that both Bcl-XL and TP53 contain miR-491-5p recognizing sites in their 3' UTRs. Overexpression of miR-491-5p in the pancreatic cancer cell line SW1990 effectively inhibited both endogenous Bcl-XL and TP53 gene expressions. Mutagenesis at the seed match region of both targeted genes further confirmed the specificity of miR491-5p recognition. Cell proliferation rate was inversely related to the increased doses of miR-491-5p. Flow cytometric analysis showed that the proportions of total apoptotic and early apoptotic cells were significantly induced as the dose of miR491-5p increased. Moreover, a mechanistic study indicated that miR-R491-5p-mediated cell apoptosis was associated with the activation of intrinsic mitochondria mediated pathways. miR491-5p also markedly inhibited mitogenic signaling pathways such as STAT3 and PI-3K/Akt, but not Ras/MAPK. Thus, our results demonstrated that miR491-5p could effectively target both Bcl-xL and TP53 and induce cell apoptosis independent of TP53.
p. 14748-14764
Received: 30 October 2012; in revised form: 30 November 2012 / Accepted: 5 December 2012 / Published: 11 December 2012
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| Download PDF Full-text (1686 KB) Abstract: A series of nitrogen-containing apigenin analogs 4a –j was synthesized via Mannich reactions to develop anticancer, antibacterial, and antioxidant agents from plant-derived flavonoids. The chemical structures of these compounds were confirmed using 1 H-NMR, 13 C-NMR, and ESI-MS. The in vitro biological activities of the analogs were evaluated via assays of their antiproliferative, antibacterial, and antioxidant activities. The prepared apigenin analogs exhibited different antiproliferative activities against four human cancer cell lines, namely human cervical (HeLa), human hepatocellular liver (HepG2), human lung (A549), and human breast (MCF-7) cancer cells. Compound 4i showed the most favorable in vitro antiproliferative activity with IC50 values of 40, 40, 223, and 166 μg/mL against HeLa, HepG2, A549, and MCF-7, respectively. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity assay also showed that 4i had the most potent antioxidant activity, with the smallest IC50 value (334.8 μg/mL). The antibacterial activities of the analogs were determined using a two-fold serial dilution technique against four pathogenic bacteria, namely Staphylococcus aureus , Bacillus subtilis , Escherichia coli , and Pseudomonas aeruginosa . All the prepared apigenin analogs exhibited more potent activities than the parent apigenin. Compounds 4h and 4j , in particular, exhibited the best inhibitory activities against the Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis with MIC values of 3.91 and 1.95 μg/mL, respectively.
p. 14765-14777
Received: 6 November 2012; in revised form: 6 December 2012 / Accepted: 7 December 2012 / Published: 11 December 2012
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| Download PDF Full-text (340 KB) Abstract: This study evaluated the anti-obesity effects of HT048, a combination of C. pinnatifida fruit and C. unshiu peel extracts, in high-fat diet (HFD)-induced obese rats. 4-Week-old male Sprague Dawley (SD) rats were divided into normal and high fat diet (HFD) groups. The HFD groups were further divided into five groups treated with distilled water, orlistat (40 mg/kg, twice daily, p.o) and HT048 (30, 100 and 300 mg/kg, twice daily, p.o.) for 12 weeks. Orlistat, an anti-obesity drug, was used as positive control in the HFD-induced obese rats. We measured the food intake, body weight, epididymal adipose tissue and liver weights, and serum total cholesterol (TC), triglyceride (TG), alanine transaminase (ALT), and aspartate aminotransferase (AST) levels. The body weight and epididymal adipose tissue and liver weights of the HT048 100 and 300 mg/kg treated groups were significantly lower than that of the HFD control group. Also, serum TC, TG, ALT, and AST levels in the HT048 100 and 300 mg/kg treated groups were significantly decreased. Moreover, the orlistat treated group showed significantly reduced body weight and improved serum lipoprotein, compared with the HFD control group. These results show that HT048 supplements improved obesity-related body weight and serum lipoprotein parameters in a HFD-induced obese rat model.
p. 14778-14794
Received: 1 November 2012; in revised form: 30 November 2012 / Accepted: 7 December 2012 / Published: 11 December 2012
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| Download PDF Full-text (830 KB) Abstract: Ginkgo biloba seeds are widely used as a food and traditional medicine in China. In the present study, a novel antioxidant protein named GBSP was purified from Ginkgo biloba seeds. The protein (GBSP) was purified by homogenization of Ginkgo biloba seed powder in saline solution, 70% ammonium sulphate precipitation, filtration on a DEAE-Cellulose52 anion exchange column, gel filtration on a Sephadex G-50 column, and preparative chromatography on a C18 column using RP-HPLC. GBSP showed an apparent molecular weight of 18 kDa by SDS-PAGE and MALDI-TOF/MS analyses. The amino acid sequence obtained by MALDI-TOF/TOF MS analysis showed GBSP was a novel protein, as no matching protein in was found the database. The protein exhibited significant antioxidant activities against free radicals such as DPPH, ABTS and superoxide anion and showed higher activity than α-tocopherol in a linoleic acid emulsion assay system. Furthermore, GBSP exhibited notable reducing power and a strong chelating effect on Cu2+ and Fe2+ . Therefore, the present study demonstrates, for the first time, that this novel protein from Ginkgo biloba seeds is an excellent antioxidant.
p. 14795-14809
Received: 9 November 2012; in revised form: 20 November 2012 / Accepted: 6 December 2012 / Published: 11 December 2012
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| Download PDF Full-text (822 KB) Abstract: Methyl-2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oate (CDDO-Me) is an synthetic oleanane triterpenoid with strong antiprolifertive and proapoptotic activities in cancer cells. However, the effect of CDDO-Me on human telomerase reverse transcriptase (hTERT) and its telomerase activity in prostate cancer cells has not been studied. We investigated the role of hTERT in mediating the anticancer activity of CDDO-Me in prostate cancer cells in vitro and in vivo . The inhibition of cell proliferation and induction of apoptosis by CDDO-Me in LNCaP and PC-3 prostate cancer cell lines was associated with the inhibition of hTERT gene expression, hTERT telomerase activity and a number of proteins that regulate hTERT transcriptionally and post-translationally. Furthermore, ablation of hTERT protein increased the sensitivity of cancer cells to CDDO-Me, whereas its overexpression rendered them resistant to CDDO-Me. In addition, inhibition of progression of preneoplastic lesions (i.e. , low and high-grade prostate intraepithelial neoplasms, PINs) to adenocarcinoma of the prostate by CDDO-Me in TRAMP mice was associated with significant decrease in TERT and its regulatory proteins in the prostate gland. These data provide evidence that telomerase is a potential target of CDDO-Me for the prevention and treatment of prostate cancer.
p. 14810-14820
Received: 2 November 2012; in revised form: 16 November 2012 / Accepted: 30 November 2012 / Published: 11 December 2012
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| Download PDF Full-text (203 KB) Abstract: Microbial transformations of racemic 7-methoxyflavanone using strains of the genus Aspergillus (A. niger KB, A. ochraceus 456) and the strain Penicillium chermesinum 113 were described. The strain A. niger KB catalysed carbonyl group reduction, leading to (±)-2,4-cis -7-methoxyflavan-4-ol. Biotransformation with the help of A. ochraceus 456 gave two products: (+)-2,4-trans -7-methoxyflavan-4-ol and 4'-hydroxy-7-methoxyflavone. Transformation by means of P. chermesinum 113 resulted in a dihydrochalcone product, 4,2'-dihydroxy-4'-methoxydihydrochalcone. DPPH scavenging activity test proved that all the biotransformations products have higher antioxidant activity that the substrate.
p. 14821-14840
Received: 16 November 2012; in revised form: 7 December 2012 / Accepted: 10 December 2012 / Published: 13 December 2012
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| Download PDF Full-text (634 KB) Abstract: The comprehensive identification of phenolic compounds in food and beverages is a crucial starting point for assessing their biological, nutritional, and technological properties. Pomegranate (Punica granatum L.) has been described as a rich source of (poly)phenolic components, with a broad array of different structures (phenolic acids, flavonoids, and hydrolyzable tannins) and a quick, high throughput, and accurate screening of its complete profile is still lacking. In the present work, a method for UHPLC separation and linear ion trap mass spectrometric (MSn ) characterization of pomegranate juice phenolic fraction was optimized by comparing several different analytical conditions. The best solutions for phenolic acids, anthocyanins, flavonoids, and ellagitannins have been delineated and more than 70 compounds have been identified and fully characterized in less than one hour total analysis time. Twenty-one compounds were tentatively detected for the first time in pomegranate juice. The proposed fingerprinting approach could be easily translated to other plant derived food extracts and beverages containing a wide array of phytochemical compounds.
p. 14841-14845
Received: 15 November 2012; in revised form: 5 December 2012 / Accepted: 5 December 2012 / Published: 13 December 2012
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| Download PDF Full-text (177 KB) Abstract: The one-pot synthesis of three dragmacidin derivatives is reported. Sarcosine anhydride (4 ) is brominated and immediately reacted with the corresponding indole to produce the products, namely 3,6-bis(5′-methoxy-3′-indolyl)-1,4-dimethylpiperazine-2,5-dione (1 ), 3,6-bis(7′-methyl-3′-indolyl)-1,4-dimethylpiperazine-2,5-dione (2 ) and 3,6-bis-(6′-chloro-3′-indolyl)-1,4-dimethylpiperazine-2,5-dione (3 ), which are characterized by 1 H-NMR.
p. 14846-14857
Received: 19 November 2012; in revised form: 9 December 2012 / Accepted: 11 December 2012 / Published: 13 December 2012
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| Download PDF Full-text (337 KB) Abstract: Synthesis of 1,3-diphenylethenylcarbazolyl-based charge transporting materials involving electron donating hydrazone moieties and an electron withdrawing 1,3-indandione moiety is reported. The obtained materials were examined by various techniques, including differential scanning calorimetry, UV-Vis spectroscopy, xerographic time of flight technique and the electron photoemission in air method. Photoemission spectra of the amorphous films of the investigated compounds showed ionization potentials of 5.54–5.90 eV. The hole drift mobility was measured by the xerographic time of flight technique. The highest hole drift mobility, exceeding 10−5 cm2 /V·s at 6.4 × 105 V/cm electric field, was observed for the 1,3-diphenylethenylcarbazolyl derivative molecularly doped with a N,N -diphenylhydrazone moiety in the polymeric host bisphenol-Z polycarbonate (PC-Z).
p. 14858-14869
Received: 11 October 2012; in revised form: 2 December 2012 / Accepted: 10 December 2012 / Published: 13 December 2012
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| Download PDF Full-text (295 KB) Abstract: Three heat resistant cross-linked PVC foam plastics were prepared and their performances were compared with universal cross-linked PVC structural foam. The results show that these three heat resistant foams have higher glass transition temperatures (close to 100 °C) than universal structural foam (83.2 °C). Compared with the universal structural foam, the three heat resistant foams show much higher decomposition temperature and better chemical stability due to the crosslinking of PVC macromolecular chains. The heat distortion temperature (HDT) values of the three heat resistant foam plastics are just a little higher than that of universal structural foam. The three heat resistant foam plastics have good dimensional stability at 140 °C, and when used as core material can closely adhere to the face plates in medium temperature curing processes. Compared with universal structural foam, the three heat resistant foam plastics have slightly better mechanical properties.
p. 14870-14881
Received: 23 November 2012; in revised form: 10 December 2012 / Accepted: 11 December 2012 / Published: 13 December 2012
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| Download PDF Full-text (278 KB) Abstract: The aim of this research was to determine chemical composition and insecticidal activity of the essential oil of Illicium pachyphyllum fruits against two grain storage insects, Sitophilus zeamais and Tribolium castaneum , and to isolate any insecticidal constituents from the essential oil. The essential oil of I . pachyphyllum fruits was obtained by hydrodistillation and analyzed by GC-MS. A total of 36 components of the essential oil were identified, with the principal compounds in the essential oil being trans -ρ-mentha-1(7),8-dien-2-ol (24.56%), D-limonene (9.79%), caryophyllene oxide (9.32%), and cis -carveol (5.26%) followed by β-caryophyllene (4.63%) and bornyl acetate. Based on bioactivity-guided fractionation, the three active constituents were isolated and identified as trans -ρ-mentha-1(7),8-dien-2-ol, D-limonene and caryophyllene oxide. The essential oil of I . pachyphyllum fruits exhibited contact toxicity against S. zeamais and T. castaneum adults, with LD50 values of 17.33 μg/adult and 28.94 μg/adult, respectively. trans -p -Mentha-1(7),8-dien-2-ol (LD50 = 8.66 μg/adult and 13.66 μg/adult, respectively) exhibited stronger acute toxicity against S . zeamais and T. castaneum adults than either caryophyllene oxide (LD50 = 34.09 μg/adult and 45.56 μg/adult) and D-limonene (LD50 = 29.86 μg/adult and 20.14 μg/adult). The essential oil of I . pachyphyllum possessed fumigant toxicity against S . zeamais and T. castaneum adults with LC50 values of 11.49 mg/L and 15.08 mg/L, respectively. trans -p -Mentha-1(7),8-dien-2-ol exhibited stronger fumigant toxicity against S . zeamais and T. castaneum adults, respectively, with LC50 values of 6.01 mg/L and 8.14 mg/L, than caryophyllene oxide (LC50 = 17.02 mg/L and 15.98 mg/L) and D-limonene (LC50 = 33.71 mg/L and 21.24 mg/L). The results indicate that the essential oil of I . pachyphyllum fruits and its constituent compounds have potential for development into natural insecticides or fumigants for the control of insects in stored grains.
p. 14882-14898
Received: 21 September 2012; in revised form: 3 December 2012 / Accepted: 5 December 2012 / Published: 13 December 2012
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| Download PDF Full-text (379 KB) Abstract: The in vitro antioxidant activities of eight 3-carboxycoumarin derivatives were assayed by the quantitative 1,1-diphenyl-2-picrylhydrazil (DPPH•) radical scavenging activity method. 3-Acetyl-6-hydroxy-2H -1-benzopyran-2-one (C1 ) and ethyl 6-hydroxy-2-oxo-2H -1-benzopyran-3-carboxylate (C2 ) presented the best radical-scavenging activity. A quantitative structure-activity relationship (QSAR) study was performed and correlated with the experimental DPPH• scavenging data. We used structural, geometrical, topological and quantum-chemical descriptors selected with Genetic Algorithms in order to determine which of these parameters are responsible of the observed DPPH• radical scavenging activity. We constructed a back propagation neural network with the hydrophilic factor (Hy) descriptor to generate an adequate architecture of neurons for the system description. The mathematical model showed a multiple determination coefficient of 0.9196 and a root mean squared error of 0.0851. Our results shows that the presence of hydroxyl groups on the ring structure of 3-carboxy-coumarins are correlated with the observed DPPH• radical scavenging activity effects.
p. 14899-14907
Received: 9 November 2012; in revised form: 29 November 2012 / Accepted: 30 November 2012 / Published: 13 December 2012
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| Download PDF Full-text (230 KB) Abstract: Two new oleanane-type triterpenoids, named platycodonoids A and B (1 , 2 ), together with five known saponins, including platycodin D (3 ), deapioplatycodin D (4 ), 3-O -β-D-glucopyranosyl polygalacic acid (5 ), 3-O -β-D-glucopyranosyl platycodigenin (6 ) and polygalacin D (7 ), were isolated from the roots of Platycodon grandiflorum . On the basis of spectral data and chemical evidence, the structures of the new compounds were elucidated as 2β,3β,23,24-tetrahydroxy-28-nor-olean-12-en-16-one (1 ) and 2β,3β,23,24- tetrahydroxy-28-nor-olean-12-en-16-one-3-O -β-D-glucopyranoside (2 ). Compounds 1 –7 were evaluated for their in vitro anti-proliferative activity against the HSC-T6 cell line.
p. 14908-14917
Received: 6 November 2012; in revised form: 15 November 2012 / Accepted: 30 November 2012 / Published: 13 December 2012
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| Download PDF Full-text (263 KB) Abstract: Shaoyao-Gancao (Paeoniae Radix Alba and Glycyrrhizae Radix et Rhizoma ) is a traditional Chinese drug pair widely used in decoctions for relieving pains, especially abdominal pain. We aimed to determine the intestinal absorption and interaction of three active compounds (glycyrrhizic acid, liquiritin, and paeoniflorin) in this drug pair. We investigated the transport of these compounds across intestinal epithelial cells by using the Caco-2 cell monolayer in both the apical-to-basolateral (A-B) and B-A directions. All compounds could only travel through the Caco-2 cell monolayer at a low level when the cells were treated with single component solutions. In the presence of verapamil, an inhibitor of P-glycoprotein (P-gp), the absorptive permeability (PAB ) of paeoniflorin and liquiritin increased significantly (p < 0.05) and efflux ratios decreased, while the absorption of glycyrrhizic acid did not change significantly, which indicated that paeoniflorin and liquiritin might be P-gp substrates. In addition, when liquiritin and glycyrrhizic acid in Gancao extract and paeoniflorin in Shaoyao extract were examined, PAB of paeoniflorin and liquiritin were significantly higher, while glycyrrhizic acid retained the same absorption level compared to the corresponding single component solutions, which suggested that some certain ingredients in the extracts can promote the absorption of paeoniflorin and liquiritin, but not that of glycyrrhizic acid. Furthermore, compared to the results of treatment with individual extracts, treatment of cells with a mixture of the two extracts considerably increased (p < 0.05) the absorption of glycyrrhizic acid and paeoniflorin and showed no change in the absorption of liquiritin, which implied that the transport of glycyrrhizic acid and paeoniflorin is increased by some ingredients from the complementary drug in the drug pair, while that of liquiritin remains unaffected.
p. 14918-14927
Received: 22 October 2012; in revised form: 19 November 2012 / Accepted: 7 December 2012 / Published: 13 December 2012
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| Download PDF Full-text (368 KB) Abstract: Flowers of Carthamus tinctorius L. are traditionally used in China to treat cerebrovascular and cardiovascular diseases. Hydroxysafflor yellow A (HSYA), the main constituent of Carthamus tinctorius L. flowers, is known for its multiple biological activities. In the present study, HSYA was isolated from Carthamus tinctorius L. flowers by a macroporous resin adsorption chromatography method coupled with a Waters high-throughput auto-purification system and it's vasodilatation effects on pulmonary artery (PA) were explored by an assay of tension study on rat pulmonary artery (PA) rings. Results suggest that HSYA possesses vascular relaxation effects on rat PA by activating the KV channel in pulmonary vascular smooth muscle cells (PVSMCs).
p. 14928-14936
Received: 26 October 2012; in revised form: 12 November 2012 / Accepted: 21 November 2012 / Published: 14 December 2012
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| Download PDF Full-text (663 KB) Abstract: Herein we report a synthesis of copper nanoparticles (Cu-NPs) in chitosan (Cts) media via a chemical reaction method. The nanoparticles were synthesized in an aqueous solution in the presence of Cts as stabilizer and CuSO4 ·5H2 O precursor. The synthesis proceeded with addition of NaOH as pH moderator, ascorbic acid as antioxidant and hydrazine as the reducing agent. The characterization of the prepared NPs was done using ultraviolet-visible spectroscopy, which showed a 593 nm copper band. The Field Emission Scanning Electron Microscope (FESEM) images were also observed, and found to be in agreement with the UV-Vis result, confirming the formation of metallic Cu-NPs. The mean size of the Cu-NPs was estimated to be in the range of 35–75 nm using X-ray diffraction. XRD was also used in analysis of the crystal structure of the NPs. The interaction between the chitosan and the synthesized NPs was studied using Fourier transform infrared (FT-IR) spectroscopy, which showed the capping of the NPs by Cts.
p. 14937-14953
Received: 10 September 2012; in revised form: 12 December 2012 / Accepted: 13 December 2012 / Published: 17 December 2012
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| Download PDF Full-text (530 KB) | Abstract: Volatile organic compounds (VOCs) are contained in a variety of chemicals that can be found in household products and may have undesirable effects on health. Thereby, it is important to model blood-to-liver partition coefficients (log Pliver ) for VOCs in a fast and inexpensive way. In this paper, we present two new quantitative structure-property relationship (QSPR) models for the prediction of log Pliver , where we also propose a hybrid approach for the selection of the descriptors. This hybrid methodology combines a machine learning method with a manual selection based on expert knowledge. This allows obtaining a set of descriptors that is interpretable in physicochemical terms. Our regression models were trained using decision trees and neural networks and validated using an external test set. Results show high prediction accuracy compared to previous log Pliver models, and the descriptor selection approach provides a means to get a small set of descriptors that is in agreement with theoretical understanding of the target property.
p. 14954-14967
Received: 13 October 2012; in revised form: 5 December 2012 / Accepted: 11 December 2012 / Published: 17 December 2012
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| Download PDF Full-text (253 KB) Abstract: Litchi fruit pericarp (LFP) contains significant amounts of phenolics which have been found to exhibit diverse biological activities. The purpose of this work was to determine the varietal differences in phenolic profiles and antioxidant activity of LFP from nine commercially available cultivars. The total phenolic and flavonoid contents ranged from 9.39 to 30.16 mg gallic acid equivalents/g fresh weight (FW) and from 7.12 to 23.46 mg catechin equivalents/g FW, respectively. The total anthocyanin contents ranged from 1.77 to 20.94 mg cyanidin-3-glucoside equivalents/100 g FW. Three anthocyanins, including cyanidin-3-rutinoside, cyanidin-3-glucoside, malvidin-3-glucoside, were detected, and cyanidin-3-rutinoside was the predominant constituent which contributes from 68.8% to 100% to total anthocyanins, The total procyanidin contents ranged from 4.35 to 11.82 mg epicatechin equivalents/g FW. Procyanidin B2, epicatechin, A-type procyanidin trimer, and procyanidin A2 were detected in all nine litchi varieties. The oxygen radical absorbance capacity activities and DPPH radical-scavenging activities ranged from 430.49 to 1752.30 μmol TE/100 g FW and from 4.70 to 11.82 mg/g (IC50), respectively. These results indicate that there are significant differences in phytochemical profiles and antioxidant activity among the tested varieties. Knowing the phenolic profiles and antioxidant activity of LFP of different varieties gives the insights into its potential application to promote health.
p. 14968-14974
Received: 31 October 2012; in revised form: 27 November 2012 / Accepted: 11 December 2012 / Published: 17 December 2012
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| Download PDF Full-text (350 KB) Abstract: pH-Zone-refining counter-current chromatography (pH-zone-refining CCC) was successfully applied for the large-scale separation of alkaloids from Corydalis bungeana . The crude extract was separated by a two-phase solvent system composed of petroleum ether–ethyl acetate–methanol–water (5:5:2:8, v/v) where triethylamine (10 mM ) was added to the upper organic stationary phase as a retainer and hydrochloric acid (5 mM ) to the aqueous mobile phase as a displacer. As a result, 285 mg of protopine, 86 mg of corynoloxine, 430 mg of coryno1ine, and 115 mg of acetylcorynoline were obtained from 3.0 g of crude extract in a one-step separation. The purities of these compounds were 99.1%, 98.3%, 99.0% and 98.5%, respectively, as determined by HPLC. The chemical structures of these isolated compounds were confirmed by ESI-MS, 1 H-NMR and 13 C-NMR.
p. 14975-14994
Received: 7 November 2012; in revised form: 11 December 2012 / Accepted: 12 December 2012 / Published: 17 December 2012
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| Download PDF Full-text (1111 KB) Abstract: Adult cardiomyocytes (CMs) have very limited capacity to regenerate. Therefore, there is a great interest in developing strategies to treat infarcted CMs that are able to regenerate cardiac tissue and promote revascularization of infarcted zones in the heart. Recently, stem cell transplantation has been proposed to replace infarcted CMs and to restore the function of the affected tissue. This area of research has become very active in recent years due to the huge clinical need to improve the efficacy of currently available therapies. Slingshot (SSH) is a family of protein phosphatases, which can specifically dephosphorylate and reactivate cofilin and inhibit the polymerization of actin filaments and actively involved in cytoskeleton rearrangement. In this study, we found that SSH1L promoted morphology changes of microfilaments during differentiation but was inhibited by the inhibitors of actin polymerization such as cytochalasin D. Overexpression of SSH1L could promote cardiac-specific protein and genes expression. 5-Aza can induce the differentiation of hMSCs into cardiomyocyte-like cells in vitro. We also observed that SSH1L efficiently promotes hMSCs differentiation into cardiomyocyte-like cells through regulation and rearrangement of cytoskeleton. Our work provides evidence that supports the positive role of SSH1L in the mechanism of stem cell differentiation into cardiomyocyte-like cells.
p. 14995-15012
Received: 16 November 2012; in revised form: 11 December 2012 / Accepted: 13 December 2012 / Published: 17 December 2012
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| Download PDF Full-text (1424 KB) Abstract: Oil palm empty fruit bunch (OPEFB) was pretreated using white-rot fungus Pleurotus floridanus , phosphoric acid or their combination, and the results were evaluated based on the biomass components, and its structural and morphological changes. The carbohydrate losses after fungal, phosphoric acid, and fungal followed by phosphoric acid pretreatments were 7.89%, 35.65%, and 33.77%, respectively. The pretreatments changed the hydrogen bonds of cellulose and linkages between lignin and carbohydrate, which is associated with crystallinity of cellulose of OPEFB. Lateral Order Index (LOI) of OPEFB with no pretreatment, with fungal, phosphoric acid, and fungal followed by phosphoric acid pretreatments were 2.77, 1.42, 0.67, and 0.60, respectively. Phosphoric acid pretreatment showed morphological changes of OPEFB, indicated by the damage of fibre structure into smaller particle size. The fungal-, phosphoric acid-, and fungal followed by phosphoric acid pretreatments have improved the digestibility of OPEFB’s cellulose by 4, 6.3, and 7.4 folds, respectively.
p. 15013-15021
Received: 12 November 2012; in revised form: 6 December 2012 / Accepted: 11 December 2012 / Published: 18 December 2012
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| Download PDF Full-text (287 KB) Abstract: Three new germacrane-type sesquiterpenoids, heishuixiecaoline A–C (compounds 1 –3 ), were isolated along with ten known compounds 4 –13 from fraction of Valeriana amurensis roots and rhizomes effective against Alzheimer’s disease (AD). The structures of 1 –3 were elucidated on the basis of their spectroscopic data. We also investigated the protective effect of compounds 1 –13 on the neurotoxicity of PC12 cells induced by amyloid-beta (Aβ25–25 ), respectively. As a result, germacrane-type sesquiterpenoids 1 –4 and lignans 5 –7 were seen to afford protection against Aβ-induced toxicity in PC 12 cells. This study will contribute to revealing the chemical basis for the therapeutic effect of V. amurensis against AD.
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