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p. 9775-9782
Received: 24 October 2011; in revised form: 15 November 2011 / Accepted: 16 November 2011 / Published: 25 November 2011
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| Download PDF Full-text (185 KB) Abstract: Phytohemical investigation on the heartwood of Dalbergia odorifera resulted in the isolation of nine flavonoids. Their structures were elucidated as sativanone (1 ), (3R )-vestitone (2 ), (3R )-2',3',7-trihydroxy-4'-methoxyisoflavanone (3 ), (3R )-4'-methoxy-2',3,7-trihydroxyisoflavanone (4 ), carthamidin (5 ), liquiritigenin (6 ), isoliquiritigenin (7 ), (3R )-vestitol (8 ), and sulfuretin (9 ) based on their spectral data. All compounds were evaluated for their inhibitory activity against Ralstonia solanacearum . This is the first report about anti-R. solanacearum activity of the compounds from D. odorifera .
p. 9783-9791
Received: 14 November 2011; in revised form: 22 November 2011 / Accepted: 22 November 2011 / Published: 25 November 2011
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| Download PDF Full-text (256 KB) Abstract: Quercetin and quercetin glycosides are physiologically active flavonol molecules that have been attributed numerous health benefits. Recovery of such molecules from plant matrices depends on a variety of factors including polarity of the extraction solvent. Among the solvents of a wide range of dielectric constants, methanol recovered the most quercetin and its glycosides from dehydrated ‘Idared’ apple peels. When ultra-sonication was employed to facilitate the extraction, exposure of 15 min of ultrasound wavelengths of dehydrated apple peel powder in 80% to 100% (v/v) methanol in 1:50 (w:v) solid to solvent ratio provided the optimum extraction conditions for quercetin and its glycosides. Acidification of extraction solvent with 0.1% (v/v) or higher concentrations of HCl led to hydrolysis of naturally occurring quercetin glycosides into the aglycone as an extraction artifact.
p. 9792-9818
Received: 17 October 2011; in revised form: 31 October 2011 / Accepted: 4 November 2011 / Published: 25 November 2011
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| Download PDF Full-text (736 KB) Abstract: The present study describes an investigation by fluorescence quenching, circular dichroism and UV-visible spectroscopy of the interaction between norfloxacin (NRF) and human serum albumin (HSA) in the presence of electromagnetic fields (EMFs). The results obtained from this study indicated that NRF had a strong ability to quench HSA at λ ex = 280 nm. In addition, a slight blue shift occurred, which suggested that the microenvironment of the protein became more hydrophobic after addition of NRF. The interaction between the NRF and HSA, whether in the absence or presence of an EMF, was considered to be a static quenching mechanism. Moreover, synchronous fluorescence demonstrated that the microenvironment around Trp became modified. Data of HSA-NRF in the presence of EMFs between 1 Hz–1 MHz confirmed the results of quenching and blue shifts. Corresponding Stern-Volmer plots were also drawn and the resultant Ksv and kq values were compared. Moreover, the binding parameters, including the number of binding sites, the binding constant and the distance, r, between donor and acceptor, were calculated based on Förster’s non-radiative energy transfer theory. According to far and near UV-CD, the formation of the complex caused changes of the secondary and tertiary structures of HSA. The obtained results are significant for patients who are subjected to high-frequency radiation as this was found to reduce the affinity of NRF to HSA.
p. 9819-9826
Received: 1 August 2011; in revised form: 11 October 2011 / Accepted: 8 November 2011 / Published: 25 November 2011
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| Download PDF Full-text (217 KB) Abstract: The antibacterial activity of two bisbenzylisoquinoline alkaloids, tetrandrine (Tet) and demethyltetrandrine (d-Tet), alone and in combination with the antibiotics ampicillin (AMP), azithromycin (AZM), cefazolin (CFZ) and levofloxacin (LEV) against 10 clinical isolates of staphylococcal chromosomal cassette mec (SCCmec) III type methicillin-resistant Staphylococcus aureus (MRSA) was studied. Susceptibility to each agent alone was tested using a broth microdilution method. The chequerboard and time-kill tests were used for the combined evaluations. The minimal inhibitory concentrations/minimal bactericidal concentrations (MICs/MBCs, μg/mL) ranges alone were 64–128/256–1,024 for both Tet and d-Tet. Significant synergies against 90% of the isolates were observed for the Tet/CFZ combination, with their MICs being reduced by 75–94% [fractional inhibitory concentration indices (FICIs) ranged from 0.188 to 0.625], respectively. An additive bactericidal result was also observed for the Tet (d-Tet)/CFZ combination in the time-kill experiments. These results demonstrated that Tet and d-Tet enhanced the in vitro inhibitory efficacy of CFZ. Their potential for combinatory therapy of patients infected with MRSA warrants further pharmacological investigation.
p. 9827-9837
Received: 8 October 2011; in revised form: 18 November 2011 / Accepted: 18 November 2011 / Published: 25 November 2011
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| Download PDF Full-text (201 KB) Abstract: The chemical composition and antimicrobial activity of essential oils obtained from leaves of two Myrtaceae species–Eugenia uniflora L. and Plinia trunciflora (O. Berg) Kausel–were determined. Analysis by GC/MS as well as determination of Kovatz indexes indicated atractylone (26.78%) and curzerene (17.96%) as major constituents of E. uniflora oil and α-cadinol (19.15%), apiole (11.15%) and cubenol (5.43%) as main components in P. trunciflora oil. Both essential oils were tested for antimicrobial activity against yeasts and bacteria. E. uniflora and P. trunciflora essential oils were active towards two Gram-positive bacteria, Streptococcus equi and Staphylococcus epidermis . In addition, biological activity of both essential oils was detected for pathogenic yeasts of the genus Candida and Cryptococcu s. E. uniflora was active towards all yeast tested and exhibited interesting minimal inhibitory concentrations (0.11 to 3.75 mg/mL) across a broad spectrum of activity.
p. 9838-9849
Received: 21 October 2011; in revised form: 7 November 2011 / Accepted: 18 November 2011 / Published: 25 November 2011
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| Download PDF Full-text (390 KB) Abstract: Synthetic dyes are extensively used and rarely degraded. Microbial decomposition is a cost-effective alternative to chemical and physical degradation processes. In this study, the decomposition of simulated anthraquinone reactive dye (Reactive Blue 19; RB19) at a concentration of 400-mg/L in wastewater by a biofilm hydrolytic-aerobic recycling system was investigated over a range of recycling fluxes. The 16S rDNA-based fingerprint technique was also used to investigate the microbial community composition. Results indicated that the recycling flux was a key factor that influenced RB19 degradation. The RB19 and COD removal efficiency could reach values as high as 82.1% and 95.4%, respectively, with a recycling flux of 10 mL/min. Molecular analysis indicated that some strains were similar to Aeromonadales , Tolumonas , and some uncultured clones were assumed to be potential decolorization bacteria. However, the microbial community composition in the reactors remained relatively stable at different recycling fluxes. This study provided insights on the decolorization capability and the population dynamics during the decolorization process of anthraquinone dye wastewater.
p. 9850-9867
Received: 31 October 2011; in revised form: 20 November 2011 / Accepted: 21 November 2011 / Published: 25 November 2011
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| Download PDF Full-text (233 KB) Abstract: Two tartary buckwheat samples (Xingku No.2 and Diqing) grown at three locations were analyzed for free and bound phenolic content and antioxidant properties. Moreover, the relative contributions of variety and growing environment to phenolic content and antioxidant properties were determined, as well as correlations of these properties to growing conditions. The total phenolic contents varied from 5,150 to 9,660 μmol of gallic acid equivalents per 100 gram of dry weight (DW) of tartary buckwheat and the free phenolics accounted for 94% to 99%. Rutin content was in the range from 518.54 to 1,447.87 mg per 100 gram of DW of tartary buckwheat. p -Hydroxybenzoic, ferulic and protocatechuic acids were the prominent phenolic acids and other phenolics, including p -coumaric, gallic, caffeic, vanillic and syringic acids were also detected. Tartary buckwheat exhibited higher DPPH· and ABTS· + scavenging activities and was more effective at preventing the bleaching of β-carotene in comparison with reference antioxidant and plant phenolics constituents. Additionally, growing conditions and the interaction between variety and environment may have more contribution than variety to individual phenolics and antioxidant properties of tartary buckwheat. Environmental parameters such as higher altitudes may also have an increasing effect on rutin and phenolic acids. This study suggests that tartary buckwheat has potential health benefits because of its high phenolic content and antioxidant properties. These components could also be enhanced by optimizing the growing conditions of a selected variety.
p. 9868-9885
Received: 7 October 2011; in revised form: 5 November 2011 / Accepted: 7 November 2011 / Published: 28 November 2011
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| Download PDF Full-text (368 KB) | Abstract: The synthesis and aromatase inhibitory activity of androst-4-en-, androst-5-en-, 1β,2β-epoxy- and/or androsta-4,6-dien-, 4β,5β-epoxyandrostane-, and 4-substituted androst-4-en-17-oxime derivatives are described. Inhibition activity of synthesized compounds was assessed using aromatase enzyme and [1β-3 H]androstenedione as substrate. Most of the compounds displayed similar to or more aromatase inhibitory activity than formestane (74.2%). 4-Chloro-3β-hydroxy-4-androsten-17-one oxime (14 , 93.8%) showed the highest activity, while 4-azido-3β-hydroxy-4-androsten-17-one oxime (17 , 32.8%) showed the lowest inhibitory activity for aromatase.
p. 9886-9899
Received: 1 November 2011; in revised form: 18 November 2011 / Accepted: 22 November 2011 / Published: 28 November 2011
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| Download PDF Full-text (426 KB) | Abstract: Dimethyl lithosermate B (DLB) is a highly potent natural antioxidant and antidiabetic polyphenol with unknown mode of action. To determine its cellular targets, a photochemical and fluorescent dimethyl lithopermate B probe was designed and efficiently synthesized. The dual-labeled chemical probe for biological application was evaluated by UV and fluorescence to determine its electrochemical absorption and emission properties. This probe could be valuable for investigating ligand-protein interactions and subcellular localization.
p. 9900-9911
Received: 11 October 2011; in revised form: 23 November 2011 / Accepted: 24 November 2011 / Published: 29 November 2011
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| Download PDF Full-text (242 KB) Abstract: Polyamidoxime chelating resin was obtained from polyacrylonitrile (PAN) grafted starch. The nitrile groups of the starch-grafted polyacrylonitrile (St-g -PAN) were converted into amidoximes by reaction with hydroxylamine under basic conditions. The synthesized graft copolymer and polyamidoxime were characterized by FTIR, TGA and elemental microanalysis. Metal chelation of the polyamidoxime resin with iron, copper and zinc has been studied. The produced metal-polyamidoxime polymer complexes were used as catalysts for the oxidation of phenol using H2 O2 as oxidizing agent. The oxidation of phenol depends on the central metal ion present in the polyamidoxime complex. Reuse of M-polyamidoxime catalyst/H2 O2 system showed a slight decrease in catalytic activities for all M-polyamidoxime catalysts.
p. 9912-9924
Received: 3 October 2011; in revised form: 18 November 2011 / Accepted: 22 November 2011 / Published: 1 December 2011
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| Download PDF Full-text (209 KB) Abstract: It has been confirmed that diabetes mellitus (DM) carries increased oxidative stress. This study evaluated the effects of salidroside from Rhodiolae Radix on diabetes-induced oxidative stress in mice. After induction of diabetes, diabetic mice were administered daily doses of 50, 100 and 200 mg/kg salidroside for 28 days. Body weights, fasting blood glucose (FBG), serum insulin, TC (total cholesterol), TG (triglyceride), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were measured. Results showed that salidroside possessed hypoglycemic activity and protective effects against diabetes-induced oxidative stress, which could significantly reduce FBG, TC, TG and MDA levels, and at same time increase serum insulin levels, SOD, GPx and CAT activities. Therefore, salidroside should be considered as a candidate for future studies on diabetes.
p. 9925-9938
Received: 22 September 2011; in revised form: 6 November 2011 / Accepted: 14 November 2011 / Published: 1 December 2011
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| Download PDF Full-text (459 KB) Abstract: One of the oldest forms of medical practice is the use of plants for the treatment and prevention of diseases that affect humans. We have studied the antimicrobial activity and synergism of Piper gaudichaudianum Kuntze with different antibiotics. The crude extract from the leaves of P. gaudichaudianum was submitted to chromatographic separation, resulting in five fractions. Fraction F3 contained a chromone (2,2-dimethyl-6-carboxycroman-4-one), and fraction F2 contained isomers that are prenylated derivatives of benzoic acid [4-hydroxy-(3',7'-dimethyl-1'-oxo-octa-E -2'-6'-dienyl)benzoic acid and 4-hydroxy-(3',7'-dimethyl-1'-oxo-octa-2'-Z -6'-dienyl) benzoic acid]. The chemical structures of both compounds were determined by analysis of 1 H-NMR, 13 C-NMR, COZY, DEPT, HMQC, and HMBC spectral data, and by comparison with data in the literature. The crude extract, fraction F2, and fraction F3 showed good activity against Staphylococcus aureus , Bacillus subtilis, and Candida tropicalis . The two benzoic acid derivatives only showed activity against S. aureus and B. subtilis . The bioauthographic analysis showed an inhibition zone only in fraction F2. Fractions F2 and F3 showed synergism in combination with ceftriaxone, tetracycline, and vancomycin. Morphological changes in form and structure were found by scanning electron microscopy in S. aureus treated with the combination of fraction F2 with vancomycin.
p. 9939-9956
Received: 28 September 2011; in revised form: 25 November 2011 / Accepted: 28 November 2011 / Published: 1 December 2011
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| Download PDF Full-text (311 KB) Abstract: Three compounds were isolated from Maytenus acanthophylla Reissek (Celastraceae): the pentacyclic triterpenes lup-20(29)-en-3β -ol (lupeol, 1 ) and 3β -lup-20(29)-en-3-yl acetate (2 ) and the carbohydrate 1,2,3,4,5,6-hexa-O -acetyldulcitol (3 ); lupeol was also isolated from Xylosma flexuosa . The compounds’ structures were elucidated by spectroscopic and spectrometric analysis. Compound 1 acts as an energy transfer inhibitor, interacting with isolated CF1 bound to thylakoid membrane, and dulcitol hexaacetate 3 behaves as a Hill reaction inhibitor and as an uncoupler, as determined by polarography. Chlorophyll a (Chl a ) fluorescence induction kinetics from the minimum yield F0 to the maximum yield FM provides information of the filling up from electrons coming from water to plastoquinone pool with reducing equivalents. In this paper we have examined the effects of compounds 1 and 3 on spinach leaf discs. Compound 1 induces the appearance of a K-band, which indicates that it inhibits the water splitting enzyme. In vivo assays measuring the fluorescence of chl a in P. ixocarpa leaves sprayed with compound 1 , showed the appearance of the K-band and the PSII reaction centers was transformed to “heat sinks” or silent reaction centers unable to reduce QA . However, 3 also induced the appearance of a K band and a new band I appears in P. ixocarpa plants, therefore it inhibits at the water splitting enzyme complex and at the PQH2 site on b6 f complex. Compounds 1 and 3 did not affect chlorophyll a fluorescence of L. perenne plants.
p. 9957-9971
Received: 2 November 2011; in revised form: 22 November 2011 / Accepted: 22 November 2011 / Published: 1 December 2011
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| Download PDF Full-text (512 KB) Abstract: Structural parameters of a range of over 100 meso -substituted zinc porphyrins were reviewed and compared to show how far the nature of the functional group may affect the interatomic distances and bond angles within the porphyrin core. It was proved that even despite evident deformations of the molecular structure, involving twisting of the porphyrin's central plane, the coupled π-bonding system remains flexible and stable. DFT calculations were applied to a number of selected porphyrins representative for the reviewed compounds to emphasize the relevance of theoretical methods in structural investigations of complex macrocyclic molecular systems. Experimental and DFT-simulated IR spectral data were reported and analyzed in context of the individual molecular features introduced by the meso substituents into the porphyrin moiety base. Raw experimental spectral data, including 1 H- and 13 C-NMR, UV-Vis, FTIR, XRD, and other relevant physicochemical details have been provided for a specially chosen reference zinc porphyrin functionalized by tert -butylphenyl groups.
p. 9972-9982
Received: 7 November 2011; in revised form: 29 November 2011 / Accepted: 30 November 2011 / Published: 2 December 2011
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| Download PDF Full-text (271 KB) Abstract: Pentylphenols 1 and 2 , cyclopropane fatty acid 3 , and cyclopentenones 4 and 5 , were isolated from an ascidian, Diplosoma sp. The structures of 1 -5 were determined by spectroscopic analysis and/or synthesis. Compound 1 inhibited the division of fertilized sea urchin eggs and compound 4 showed mild cytotoxity against HCT116 cells (human colorectal cancer cell).
p. 9983-10001
Received: 2 November 2011; in revised form: 21 November 2011 / Accepted: 21 November 2011 / Published: 2 December 2011
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| Download PDF Full-text (254 KB) Abstract: The Leydig cells of the testis have the capacity to biosynthesize testosterone from cholesterol. Testosterone and its metabolically activated product dihydrotestosterone are critical for the development of male reproductive system and spermatogenesis. At least four steroidogenic enzymes are involved in testosterone biosynthesis: Cholesterol side chain cleavage enzyme (CYP11A1) for the conversion of cholesterol into pregnenolone within the mitochondria, 3β-hydroxysteroid dehydrogenase (HSD3B), for the conversion of pregnenolone into progesterone, 17α-hydroxylase/17,20-lyase (CYP17A1) for the conversion of progesterone into androstenedione and 17β-hydroxysteroid dehydrogenase (HSD17B3) for the formation of testosterone from androstenedione. Testosterone is also metabolically activated into more potent androgen dihydrotestosterone by two isoforms 5α-reductase 1 (SRD5A1) and 2 (SRD5A2) in Leydig cells and peripheral tissues. Many endocrine disruptors act as antiandrogens via directly inhibiting one or more enzymes for testosterone biosynthesis and metabolic activation. These chemicals include industrial materials (perfluoroalkyl compounds, phthalates, bisphenol A and benzophenone) and pesticides/biocides (methoxychlor, organotins, 1,2-dibromo-3-chloropropane and prochloraz) and plant constituents (genistein and gossypol). This paper reviews these endocrine disruptors targeting steroidogenic enzymes.
(This article belongs to the Special Issue
Steroids )
p. 10002-10012
Received: 3 November 2011; in revised form: 24 November 2011 / Accepted: 25 November 2011 / Published: 2 December 2011
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| Download PDF Full-text (173 KB) Abstract: The present study was undertaken to evaluate the protection potential of ethanol extract of Salvia miltiorrhiza (SMEE) against oxidative injury in the ischemia-reperfusion (I/R) model of rats in vivo . Rats were divided into six groups of 10 rats each. Group I/R model and sham were fed with a standard rat chow, groups SMEE I and SMEE II were fed with a standard rat chow and 400 or 800 mg/kg b.w. ethanol extract for 12 days before the beginning of I/R studies. Positive control group was fed with a standard rat chow and salvianolic acid B (55 mg/kg b.w.) or tanshinone II-A (55 mg/kg b.w.) for 12 days before the beginning of I/R studies. To produce I/R, the left anterior descending artery (LAD) was occluded in anesthetized rats for 15 min, followed by 120 min reperfusion. Infarct sizes were found significantly decreased in SMEE-treated and positive control groups compared to I/R model group. Serum AST, LDH and CK-MB activities were significantly reduced and myocardium Na+ -K+ ATPase, Ca2+ -Mg2+ ATPase activities and antioxidant enzyme activities (SOD, CAT, GSH-Px) were markedly increased in SMEE-treated and salvianolic acid B or tanshinone II-A positive control groups compared to the I/R model group. Pretreatment of S. miltiorrhiza ethanol extract and salvianolic acid B or tanshinone II-A dose-dependently reduced significantly myocardium MDA level, ROS and NOS activities and enhanced myocardium GSH level in I/R rats compared to I/R rats model. In conclusion, we clearly demonstrated that S. miltiorrhiza ethanol extract pretreatment can decrease oxidative injury in rats subjected to myocardial I/R.
p. 10013-10028
Received: 18 November 2011 / Accepted: 30 November 2011 / Published: 5 December 2011
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| Download PDF Full-text (316 KB) Abstract: YS-121 [2-(4-chloro-6-(2,3-dimethylphenylamino)pyrimidin-2-ylthio)octanoic acid] is the result of target-oriented structural derivatization of pirinixic acid. It is a potent dual PPARα /γ -agonist, as well as a potent dual 5-LO/mPGES-1-inhibitor. Additionally, recent studies showed an anti-inflammatory efficacy in vivo . Because of its interference with many targets, YS-121 is a promising drug candidate for the treatment of inflammatory diseases. Ongoing preclinical studies will thus necessitate huge amounts of YS-121. To cope with those requirements, we have optimized the synthesis of YS-121. Surprisingly, we isolated and characterized byproducts during the resulting from nucleophilic aromatic substitution reactions by different tertiary alkylamines at a heteroaromatic halide. These amines should actually serve as assisting bases, because of their low nucleophilicity. This astonishing fact was not described in former publications concerning that type of reaction and, therefore, might be useful for further reaction improvement in general. Furthermore, we could develop a proposal for the mechanism of that byproduct formation.
p. 10029-10045
Received: 5 September 2011; in revised form: 16 November 2011 / Accepted: 24 November 2011 / Published: 5 December 2011
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| Download PDF Full-text (430 KB) Abstract: The supercritical fluid extraction (SFE) of Lepidium apetalum seed oil and its anti-oxidant activity were studied. The SFE process was optimized using response surface methodology (RSM) with a central composite design (CCD). Independent variables, namely operating pressure, temperature, time and flow rate were evaluated. The maximum extraction of Lepidium apetalum seed oil by SFE-CO2 (about 36.3%) was obtained when SFE-CO2 extraction was carried out under the optimal conditions of 30.0 MPa of pressure, 70 °C of temperature, 120 min of extraction time and 25.95 L/h of flow rate. GC-MS analysis showed the presence of four fatty acids in Lepidium apetalum seed oil, with a high content (91.0%) of unsaturated fatty acid. The anti-oxidant activity of the oil was assessed by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay and 2,2′-azino- bis(3-ethylbenzthiazoline-6-sulphonic acid) diammonium salt (ABTS) test. Lepidium apetalum seed oil possessed a notable concentration-dependent antioxidant activity, with IC50 values of 1.00 and 3.75 mg/mL, respectively.
p. 10046-10058
Received: 4 November 2011; in revised form: 28 November 2011 / Accepted: 30 November 2011 / Published: 5 December 2011
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| Download PDF Full-text (931 KB) Abstract: Transglutaminase (TGase) was cross-linked with glutaraldehyde, and cross-linked crystalline transglutaminase was immobilized on a polypropylene microporous membrane by UV-induced grafting. Immobilized enzyme activity were calculated to be 0.128 U/cm2 polypropylene microporous membrane. The microstructure and enzyme characteristics of free, cross-linked and immobilized transglutaminase were compared. The optimum temperature of free transglutaminase was determined to be approximately 40 °C, while cross-linking and immobilization resulted in an increase to approximately 45 °C and 50 °C. At 60 °C, immobilized, cross-linked and free transglutaminase retained 91.7 ± 1.20%, 63.2 ± 1.05% and 37.9 ± 0.98% maximum activity, respectively. The optimum pH was unaffected by the state of transglutaminase. However, the thermal and pH stabilities of cross-linked and immobilized transglutaminase were shown to increase.
p. 10059-10077
Received: 10 October 2011; in revised form: 18 November 2011 / Accepted: 1 December 2011 / Published: 6 December 2011
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| Download PDF Full-text (1136 KB) Abstract: Gold nanoparticles were prepared by electrochemical deposition on highly oriented pyrolytic graphite (HOPG) and boron-doped, epitaxial 100-oriented diamond layers. Using a potentiostatic double pulse technique, the average particle size was varied in the range from 5 nm to 30 nm in the case of HOPG as a support and between < 1 nm and 15 nm on diamond surfaces, while keeping the particle density constant. The distribution of particle sizes was very narrow, with standard deviations of around 20% on HOPG and around 30% on diamond. The electrocatalytic activity towards hydrogen evolution and oxygen reduction of these carbon supported gold nanoparticles in dependence of the particle sizes was investigated using cyclic voltammetry. For oxygen reduction the current density normalized to the gold surface (specific current density) increased for decreasing particle size. In contrast, the specific current density of hydrogen evolution showed no dependence on particle size. For both reactions, no effect of the different carbon supports on electrocatalytic activity was observed.
p. 10078-10092
Received: 19 October 2011; in revised form: 25 November 2011 / Accepted: 28 November 2011 / Published: 6 December 2011
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| Download PDF Full-text (282 KB) | Abstract: Pecan is an important horticultural nut crop originally from North America and now widely cultivated in China for its high ecological, ornamental and economic value. Currently, there are over one hundred cultivars grown in China, including introduced American cultivars and Chinese seedling breeding cultivars. Molecular markers were used to assess the genetic diversity of these cultivars and to identify the pedigrees of fine pecan plants with good characteristics and no cultivar-related data. A total of 77 samples grown in China were studied, including 14 introduced cultivars, 12 domestic seedling breeding cultivars, and 49 fine pecan plants with no cultivar data, together with Carya cathayensis and Juglans nigra . A total of 77 ISSR and 19 SSR primers were prescreened; 10 ISSR and eight SSR primers were selected, yielding a total of 94 amplified bands (100% polymorphic) in the range of 140–1,950 bp for the ISSR and 70 amplified bands (100% polymorphic) in the range of 50–350 bp for SSR markers. Genetic diversity analyses indicated Chinese-grown pecan cultivars and fine plants had significant diversity at the DNA level. The dengrograms constructed with ISSR, SSR or combined data were very similar, but showed very weak grouping association with morphological characters. However, the progeny were always grouped with the parents. The great diversity found among the Chinese cultivars and the interesting germplasm of the fine pecan plants analyzed in this study are very useful for increasing the diversity of the pecan gene pool. All 77 accessions in this study could be separated based on the ISSR and SSR fingerprints produced by one or more primers. The results of our study also showed that ISSR and SSR techniques were both suitable for genetic diversity analyses and the identification of pecan resources.
p. 10093-10103
Received: 21 October 2011; in revised form: 24 November 2011 / Accepted: 29 November 2011 / Published: 6 December 2011
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| Download PDF Full-text (228 KB) Abstract: To investigate the protective effects of protopanaxadiol-type ginsenoside (PDG) and its metabolite ginsenoside M1 (G-M1) on carbon tetrachloride (CCl4 )-induced chronic liver injury in ICR mice, we carried out conversion of protopanaxadiol-type ginsenosides to ginsenoside M1 using snailase. The optimum time for the conversion was 24 h at a constant pH of 4.5 and an optimum temperature of 50 °C. The transformation products were identified by high-performance liquid chromatography and electrospray ion-mass spectrometry. Subsequently, most of PDG was decomposed and converted into G-M1 by 24 h post-reaction. During the study on hepatoprotective in a mice model of chronic liver injury, PDG or G-M1 supplement significantly ameliorated the CCl4 -induced liver lesions, lowered the serum levels of select hepatic enzyme markers (alanine aminotransferase, ALT, and aspartate aminotransferase, AST) and malondialdehyde and increased the activity of superoxide dismutase in liver. Histopathology of the liver tissues showed that PDG and G-M1 attenuated the hepatocellular necrosis and led to reduction of inflammatory cell infiltration. Therefore, the results of this study show that PDG and G-M1 can be proposed to protect the liver against CCl4 -induced oxidative injury in mice, and the hepatoprotective effect might be attributed to amelioration of oxidative stress.
p. 10104-10122
Received: 13 October 2011; in revised form: 22 November 2011 / Accepted: 23 November 2011 / Published: 6 December 2011
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| Download PDF Full-text (261 KB) Abstract: Total phenolic contents (TPC), total flavonoid contents (TFC), related antioxidative and antiradical capabilities of grape cane extracts from 11 varieties (five V. vinifera cultivars and six Chinese wild grapes) widely grown in China were evaluated. Antioxidant properties were determined as DPPH and ABTS radical-scavenging abilities, superoxide anion and hydroxyl radical and hydrogen peroxide scavenging assays, as well as reducing power. Phenolic profiles of the extracts were characterized by using high-performance liquid chromatography (HPLC) techniques. All extracts exhibited strong antioxidant and effective free radical inhibition activities (EC50 values), which generally correlated negatively with TPC (r = −0.804 to −0.918) and TFC (r = −0.749 to −0.888). In comparison with gallic acid, Trolox and tert -butylhydroquinone (positive controls), most grape cane extracts showed more efficient scavenging effects toward different reactive oxygen species. HPLC analysis revealed the presence of (+)-catechin, (−)-epicatechin, and trans -resveratrol as major phenolic components in the extracts. These results suggest that grape cane extracts may serve as a potential source of natural antioxidant for food and pharmaceutical application.
p. 10123-10133
Received: 4 November 2011; in revised form: 28 November 2011 / Accepted: 30 November 2011 / Published: 6 December 2011
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| Download PDF Full-text (1004 KB) Abstract: Icariin had been reported as a potential agent for osteogenesis, but the dose-effect relationship needed further research to realize the clinical application of icariin. We isolated and purified human bone mesenchymal stem cells (hBMSCs) and stimulated them with different concentrations of icariin. The cytotoxicity of icariin was evaluated by the methylthiazolytetrazolium (MTT) assay method. The proliferation and osteogenic differentiation of such hBMSCs were investigated for different concentrations of icariin. We found that icariin had a dose-dependent effect on the proliferation and osteogenic differentiation of hBMSCs in a suitable concentration range from 10− 9 M to 10− 6 M, but at concentrations above 10− 5 M, the cytotoxicity limited its use. The extremely low cost of icariin and its high abundance make it appealing for bone regeneration.
p. 10134-10145
Received: 10 October 2011; in revised form: 29 November 2011 / Accepted: 30 November 2011 / Published: 6 December 2011
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| Download PDF Full-text (767 KB) Abstract: Background and Aim: Clitoria ternatea , a medicinal herb native to tropical equatorial Asia, is commonly used in folk medicine to treat various diseases. The aim of the present study is to evaluate the hepatoprotective and antioxidant activity of C. ternatea against experimentally induced liver injury. Methods: The antioxidant property of methanolic extract (ME) of C. ternatea leaf was investigated by employing an established in vitro antioxidant assay. The hepatoprotective effect against paracetamol-induced liver toxicity in mice of ME of C. ternatea leaf was also studied. Activity was measured by monitoring the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and billirubin along with histopathological analysis. Results: The amount of total phenolics and flavonoids were estimated to be 358.99 ± 6.21 mg/g gallic acid equivalent and 123.75 ± 2.84 mg/g catechin equivalent, respectively. The antioxidant activity of C. ternatea leaf extract was 67.85% at a concentration of 1 mg/mL and was also concentration dependant, with an IC50 value of 420.00 µg/mL. The results of the paracetamol-induced liver toxicity experiments showed that mice treated with the ME of C. ternatea leaf (200 mg/kg) showed a significant decrease in ALT, AST, and bilirubin levels, which were all elevated in the paracetamol group (p < 0.01). C. ternatea leaf extract therapy also protective effects against histopathological alterations. Histological studies supported the biochemical findings and a maximum improvement in the histoarchitecture was seen. Conclusions: The current study confirmed the hepatoprotective effect of C. ternatea leaf extract against the model hepatotoxicant paracetamol. The hepatoprotective action is likely related to its potent antioxidative activity.
p. 10146-10156
Received: 20 October 2011; in revised form: 22 November 2011 / Accepted: 1 December 2011 / Published: 6 December 2011
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| Download PDF Full-text (442 KB) Abstract: Neurogenesis is a complex process, which contributes to the ability of the adult brain to function normally and adapt to diseases. Epidermal growth factor (EGF) is known to play an important role in neurogenesis; however, the underlying mechanism is still unclear. Here, we hypothesized that brain-derived neurotrophic factor (BDNF) can enhance the effect of EGF on neurogenesis. Using in vitro cell culture of aborted human fetal brain tissues, we investigated proliferation and migration of neural stem/progenitor cells (NSPCs) after treatment with EGF and different concentrations of BDNF. EGF stimulated proliferation and migration of NSPCs, and this effect was significantly enhanced by co-incubation with BDNF. In the NSPCs treated with 50 ng/mL BDNF, BrdU incorporation was significantly increased (from 7.91% to 17.07%), as compared with that in the control. Moreover, the number of migrating cells was at least 2-fold higher than that in the control. Furthermore, phosphorylation of Akt-1 was increased by BDNF treatment, as well. By contrast, the enhancing effect of BDNF on EGF-induced proliferation and migration of NSPCs were abolished by an inhibitor of PI3K, LY294002. These findings suggest that BDNF promotes EGF-induced proliferation and migration of NSPC through the PI3K/Akt pathway, providing significant insights into not only the mechanism underlying EGF-induced neurogenesis but also potential neuronal replacement strategies to treat brain damage.
p. 10157-10167
Received: 24 October 2011; in revised form: 23 November 2011 / Accepted: 29 November 2011 / Published: 7 December 2011
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| Download PDF Full-text (264 KB) Abstract: An activity-directed fractionation and purification process was used to isolate antioxidant components from cassava stems produced in Hainan. The ethyl acetate and n -butanol fractions showed greater DPPH˙and ABTS·+ scavenging activities than other fractions. The ethyl acetate fraction was subjected to column chromatography, to yield ten phenolic compounds: Coniferaldehyde (1 ), isovanillin (2 ), 6-deoxyjacareubin (3 ), scopoletin (4 ), syringaldehyde (5 ), pinoresinol (6 ), p -coumaric acid (7 ), ficusol (8 ), balanophonin (9 ) and ethamivan (10 ), which possess significant antioxidant activities. The relative order of DPPH· scavenging capacity for these compounds was ascorbic acid (reference) > 6 > 1 > 8 > 10 > 9 > 3 > 4 > 7 > 5 > 2 , and that of ABTS·+ scavenging capacity was 5 > 7 > 1 > 10 > 4 > 6 > 8 > 2 > Trolox (reference compound) > 3 > 9 . The results showed that these phenolic compounds contributed to the antioxidant activity of cassava.
p. 10168-10186
Received: 10 November 2011 / Accepted: 30 November 2011 / Published: 7 December 2011
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| Download PDF Full-text (635 KB) | Abstract: We present three versatile solid-supported scaffold building blocks based on the (deoxy)cholic acid framework and decorated with handles for further derivatization by modern ligation techniques such as click chemistry, Staudinger ligation or native chemical ligation. Straightforward procedures are presented for the synthesis and analysis of the steroid constructs. These building blocks offer a new, facile and shorter access route to bile acid-peptide conjugates on solid-phase with emphasis on heterodipodal conjugates with defined spatial arrangements. As such, we provide versatile new synthons to the toolbox for bile acid decoration.
(This article belongs to the Special Issue
Steroids )
p. 10187-10201
Received: 10 October 2011; in revised form: 1 December 2011 / Accepted: 2 December 2011 / Published: 7 December 2011
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| Download PDF Full-text (245 KB) Abstract: 2-(6,8-Dibromo-2-methylquinazolin-4-yloxy)-acetohydrazide (4 ) was prepared by the reaction of 6,8-dibromo-2-methylbenzo-[d ][1,3]oxazin-4-one with formamide to afford quinazolinone 2 , followed by alkylation with ethyl chloroacetate to give the ester 3 . Treatment of ester 3 with hydrazine hydrate and benzaldehyde afforded 4 and styryl quinazoline 5 . The hydrazide was reacted with triethyl orthoformate, acetylacetone and ethyl acetoacetate and benzaldehyde derivatives to afford the corresponding pyrazoles 6 , 7 , 9 and hydrazone derivatives 10a-c . Cyclization of hydrazones 10a-c with thioglycolic acid afforded the thiazole derivatives 11a-c . Reaction of the hydrazide with isothiocyanate derivatives afforded hydrazinecarbothioamide derivatives 12a-c , which cyclized to triazole-3-thiols and thiadiazoles 13a-c and 14a-c , respectively. Fusion of the hydrazide with phthalimide afforded the annelated compound 1,2,4-triazolo[3,4-a ]isoindol-5-one (15 ). The newly synthesized compounds were characterized by their spectral (IR, 1 H-, 13 C-NMR) data. Selected compounds were screened for analgesic activity.
p. 10202-10213
Received: 2 November 2011; in revised form: 20 November 2011 / Accepted: 24 November 2011 / Published: 8 December 2011
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| Download PDF Full-text (247 KB) Abstract: A ‘Heat treatment aqueous two phase system’ was employed for the first time to purify serine protease from kesinai (Streblus asper ) leaves. In this study, introduction of heat treatment procedure in serine protease purification was investigated. In addition, the effects of different molecular weights of polyethylene glycol (PEG 4000, 6000 and 8000) at concentrations of 8, 16 and 21% (w/w) as well as salts (Na-citrate, MgSO4 and K2 HPO4 ) at concentrations of 12, 15, 18% (w/w) on serine protease partition behavior were studied. Optimum conditions for serine protease purification were achieved in the PEG-rich phase with composition of 16% PEG6000-15% MgSO4 . Also, thermal treatment of kesinai leaves at 55 °C for 15 min resulted in higher purity and recovery yield compared to the non-heat treatment sample. Furthermore, this study investigated the effects of various concentrations of NaCl addition (2, 4, 6 and 8% w/w) and different pH (4, 7 and 9) on the optimization of the system to obtain high yields of the enzyme. The recovery of serine protease was significantly enhanced in the presence of 4% (w/w) of NaCl at pH 7.0. Based on this system, the purification factor was increased 14.4 fold and achieved a high yield of 96.7%.
p. 10214-10226
Received: 27 November 2011 / Accepted: 7 December 2011 / Published: 8 December 2011
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| Download PDF Full-text (357 KB) Abstract: Nine compounds have been isolated from the ethyl acetate soluble fraction of C. sinensis , namely protocatechuic acid (1 ), trans -caffeic acid (2 ), methyl rosmarinate (3 ), rosmarinic acid (4 ), kaempferide-3-O -β -D-glucopyranoside (5 ), kaempferol-3-O -β -D-glucopyranoside (6 ), quercetin-3-O -β -D-glucopyranoside (7 ), kaempferide-3-O -α-L-rhamnopyranosyl (1→6)-β -D-glucopyranoside (8 ) and kaempferol-3-O -α-L-rhamno-pyranosyl (1→6)-β -D-glucopyranoside (9 ), all reported for the first time from this species. The structures of these compounds were deduced on the basis of spectroscopic studies, including 1D and 2D NMR techniques. Compounds 1–9 were investigated for biological activity and showed significant anti-inflammatory activity in the carrageen induced rat paw edema test. The antioxidant activities of isolated compounds 1–9 were evaluated by the DPPH radical scavenging test, and compounds 1 , 2 , 4 and 7 –9 exhibited marked scavenging activity compared to the standard BHA. These compounds were further studied for their anti-glycation properties and some compounds showed significant anti-glycation inhibitory activity. The purity of compounds 2 –5 , 8 and 9 was confirmed by HPLC. The implications of these results for the chemotaxonomic studies of the genus Cordia have also been discussed.
p. 10227-10255
Received: 6 September 2011; in revised form: 6 December 2011 / Accepted: 8 December 2011 / Published: 8 December 2011
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| Download PDF Full-text (624 KB) Abstract: The M2 channel protein on the influenza A virus membrane has become the main target of the anti-flu drugs amantadine and rimantadine. The structure of the M2 channel proteins of the H3N2 (PDB code 2RLF) and 2009-H1N1 (Genbank accession number GQ385383) viruses may help researchers to solve the drug-resistant problem of these two adamantane-based drugs and develop more powerful new drugs against influenza A virus. In the present study, we searched for new M2 channel inhibitors through a combination of different computational methodologies, including virtual screening with docking and pharmacophore modeling. Virtual screening was performed to calculate the free energies of binding between receptor M2 channel proteins and 200 new designed ligands. After that, pharmacophore analysis was used to identify the important M2 protein-inhibitor interactions and common features of top binding compounds with M2 channel proteins. Finally, the two most potential compounds were determined as novel leads to inhibit M2 channel proteins in both H3N2 and 2009-H1N1 influenza A virus.
p. 10256-10268
Received: 11 November 2011; in revised form: 23 November 2011 / Accepted: 28 November 2011 / Published: 8 December 2011
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| Download PDF Full-text (399 KB) Abstract: Irradiation of 1-substituted benzotriazole arylhydrazones 3a –c , 4a ,b and 5a ,b with a 16 W low pressure mercury arc-lamp (254 nm) for 24 h gave phenanthridin-6-yl-2-phenyldiazines 9a –c , phenanthridin-6(5H )-ones 10a –c , 1-anilinobenzimidazoles 11a –c , 2-aryl-1H -benzimidazoles 12a –c , 1-arylamino-1H- benzimidazol-2-carboxylic acid ethyl esters 14a ,b , 1-aryl-1H , 9H -benzo [4,5][1,2,3] triazolo[1,2-a ]tetrazole-3-carboxylic acid ethyl esters 16a ,b , 1-arylamino-2-benzoylbenzimidazoles 18a ,b and 2-benzoylbenzoxazole 21 .
p. 10269-10291
Received: 14 October 2011; in revised form: 5 November 2011 / Accepted: 10 November 2011 / Published: 9 December 2011
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| Download PDF Full-text (834 KB) Abstract: This study reports the synthesis and characterization of novel ruthenium (II) complexes with the polydentate dipeptide, L-carnosine (2-[(3-aminopropanoyl)amino]-3-(1H -imidazol-5-yl)propanoic acid). Mixed-ligand complexes with the general composition [MLp (Cl)q (H2 O)r ]·xH2 O (M = Ru(II); L = L-carnosine; p = 3 − q; r = 0–1; and x = 1–3) were prepared by refluxing aqueous solutions of the ligand with equimolar amounts of ruthenium chloride (black-alpha form) at 60 °C for 36 h. Physical properties of the complexes were characterized by elemental analysis, DSC/TGA, and cyclic voltammetry. The molecular structures of the complexes were elucidated using UV-Vis, ATR-IR, and heteronuclear NMR spectroscopy, then confirmed by density function theory (DFT) calculations at the B3LYP/LANL2DZ level. Two-dimensional NMR experiments (1 H COSY, 13 C gHMBC, and 15 N gHMBC) were also conducted for the assignment of chemical shifts and calculation of relative coordination-induced shifts (RCIS) by the complex formed. According to our results, the most probable coordination geometries of ruthenium in these compounds involve nitrogen (N1) from the imidazole ring and an oxygen atom from the carboxylic acid group of the ligand as donor atoms. Additional thermogravimetric and electrochemical data suggest that while the tetrahedral-monomer or octahedral-dimer are both possible structures of the formed complexes, the metal in either structure occurs in the (2+) oxidation state. Resulting RCIS values indicate that the amide-carbonyl, and the amino-terminus of the dipeptide are not involved in chelation and these observations correlate well with theoretical shift predictions by DFT.
p. 10292-10302
Received: 11 November 2011; in revised form: 28 November 2011 / Accepted: 29 November 2011 / Published: 12 December 2011
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| Download PDF Full-text (245 KB) Abstract: A series of new coumarin derivatives 4 containing a 4-arylbut-3-en-2-one moiety were synthesized by condensation of 3-acetylcoumarin 1 with aryl aldehydes 2 in chloroform in the presence of piperidine. The interactions of 3-formyl-4-chlorocoumarin (3 ) with nitrogen-containg nucleophiles leading to the corresponding substituted chromen-[4,3-c]pyrazol-4-ones 5 are described. The structures of the obtained compounds were established on the basis of 1D NMR, 2D NMR and IR and further the compounds were evaluated for possible antioxidant activities. The coumarinic chalcone 4a has been found to be the most active (IC50 = 2.07 μM) in this study.
p. 10303-10313
Received: 31 October 2011; in revised form: 25 November 2011 / Accepted: 5 December 2011 / Published: 13 December 2011
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| Download PDF Full-text (379 KB) Abstract: In the course of our studies on the regioselective carbon-oxygen bond cleavage of the benzylidene acetal group of hexopyranosides with a reducing agent, we found that a combination of a Lewis acid and a reducing agent triggered a ring-opening reaction of the pyranose ring of methyl α-D-allopyranosides. The formation of an acyclic boronate ester by the attachment of a hydride ion at C-1 indicated that the unexpected endocyclic cleavage of the bond between the anomeric carbon atom and the pyranose ring oxygen atom proceeded via an oxacarbenium ion intermediate produced by the chelation between O5/O6 of the pyranoside and the Lewis acid, followed by nucleophile substitution with a hydride ion at C1.
p. 10314-10323
Received: 3 November 2011; in revised form: 1 December 2011 / Accepted: 5 December 2011 / Published: 13 December 2011
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| Download PDF Full-text (368 KB) Abstract: Antimony(V) and bismuth(V) complexes of lapachol have been synthesized by the reaction of Ph3 SbCl2 or Ph3 BiCl2 with lapachol (Lp) and characterized by several physicochemical techniques such as IR, and NMR spectroscopy and X-ray crystallography. The compounds contain six-coordinated antimony and bismuth atoms. The antimony(V) complex is a monomeric derivative, (Lp)(Ph3 Sb)OH, and the bismuth(V) complex is a dinuclear compound bridged by an oxygen atom, (Lp)2 (Ph3 Bi)2 O. Both compounds inhibited the growth of a chronic myelogenous leukemia cell line and the complex of Bi(V) was about five times more active than free lapachol. This work provides a rare example of an organo-Bi(V) complex showing significant cytotoxic activity.
p. 10324-10336
Received: 7 November 2011; in revised form: 4 December 2011 / Accepted: 6 December 2011 / Published: 13 December 2011
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| Download PDF Full-text (227 KB) Abstract: The immunomodulatory function of longan pulp polysaccharide-protein complex (LP3) was investigated in immunosuppressed mice models. Compared with the model control, peroral administration of 100 mgkg−1 d−1 LP3 could significantly increase/enhance antibody production against chicken red blood cell (CRBC), concanavalin A (ConA)-induced splenocyte proliferation, macrophage phagocytosis, NK cell cytotoxicity against YAC-1 lymphoma cell, and interferon-gamma (INF-γ) and interleukin-2 (IL-2) secretion in serum (P < 0.05). The immunomodulatory effects, except for those on splenocytes and macrophages (P > 0.05), were also observed in mice administered with 50 or 200 mgkg−1 d−1 LP3 (P < 0.05). The beneficial effects of 50–200 mgkg−1 d−1 LP3 were comparable to those of 50 mgkg−1 d−1 ganoderan. The strong immunomodulatory activity of LP3 confirmed its good potential as an immunotherapeutic adjuvant.
p. 10337-10346
Received: 20 November 2011; in revised form: 5 December 2011 / Accepted: 6 December 2011 / Published: 14 December 2011
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| Download PDF Full-text (265 KB) Abstract: The synthesis of some novel alkyl/aryl substituted tertiary alcohols was accomplished in two steps. The synthetic route involves preparation of Grignard reagents by treating alkyl/aryl bromides with magnesium turnings in dry ether. Then substituted chalcones were reacted with the Grignard reagents to afford alkyl/aryl substituted tertiary alcohols 1-10. The structures of the synthesized compounds were assigned on the basis of FT-IR, 1 H-NMR, 13 C-NMR and mass spectroscopic data. The in vivo anti-inflammatory activity of the synthesized compounds was evaluated using the carrageenan-induced hind paw edema method and was compared with that of ibuprofen. Some of the newly synthesized compounds showed promising anti-inflammatory activity. The tertiary alcohols 1-10 were also screened for antibacterial activity against ten bacterial strains using seven Gram-positive and three Gram-negative bacteria and for antifungal activity against Aspergillus Flavus , Aspergillus Niger and Aspergillus pterus. Tertiary alcohols 1-10 were found to exhibit good to excellent antimicrobial activities compared to levofloxacin and fluconazole used as standard drugs.
p. 10347-10356
Received: 10 November 2011; in revised form: 25 November 2011 / Accepted: 5 December 2011 / Published: 14 December 2011
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| Download PDF Full-text (254 KB) | Abstract: The purpose of this research was to prepare floating calcium alginate beads of berberine for targeting the gastric mucosa and prolonging their gastric residence time. The floating beads were prepared by suspending octodecanol and berberine in sodium alginate (SA) solution. The suspension was then dripped into a solution of calcium chloride. The hydrophobic and low-density octodecanol enhanced the sustained-release properties and floating ability of the beads. The bead formulation was optimized for different weight ratios of octodecanol and SA and evaluated in terms of diameter, floating ability and drug loading, entrapment and release. In vitro release studies showed that the floating and sustained release time were effectively increased in gastric media by addition of octodecanol. In vivo studies with rats showed that a significant increase in gastric residence time of beads had been achieved.
p. 10357-10369
Received: 10 November 2011; in revised form: 5 December 2011 / Accepted: 7 December 2011 / Published: 14 December 2011
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| Download PDF Full-text (293 KB) | Abstract: By bioguided fractionation of the hexane extract of Commiphora erythraea resin we isolated four furanosesquiterpenoids that were tested for their protective activity against oxidative stress. Furanodienone and 1,10(15)-furanogermacra-dien-6-ones showed to be potent inhibitors of lipid peroxidation (IC50 of ~0.087 μM), being more active than the methoxylated analogues. Furthermore, using BV2 microglial cells, we found that furanodienone from C. erythraea is able to counteract LPS-induced cell death and decrease LPS-induced NO generation thus protecting microglial cells from LPS-induced cytotoxicity. Finally, docking studies were undertaken to gain insight into the possible binding mode of the isolated compounds at 5-LOX binding site.
p. 10370-10386
Received: 16 October 2011; in revised form: 17 November 2011 / Accepted: 21 November 2011 / Published: 14 December 2011
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| Download PDF Full-text (582 KB) Abstract: The photocatalytic degradation of two commercial textile azo dyes, namely C.I Reactive Black 5 and C.I Reactive Red 239, has been studied. TiO2 P25 Degussa was used as catalyst and photodegradation was carried out in aqueous solution under artificial irradiation with a 125 W mercury vapor lamp. The effects of the amount of TiO2 used, UV-light irradiation time, pH of the solution under treatment, initial concentration of the azo dye and addition of different concentrations of hydrogen peroxide were investigated. The effect of the simultaneous photodegradation of the two azo dyes was also investigated and we observed that the degradation rates achieved in mono and bi-component systems were identical. The repeatability of photocatalytic activity of the photocatalyst was also tested. After five cycles of TiO2 reuse the rate of colour lost was still 77% of the initial rate. The degradation was followed monitoring the change of azo dye concentration by UV-Vis spectroscopy. Results show that the use of an efficient photocatalyst and the adequate selection of optimal operational parameters may easily lead to a complete decolorization of the aqueous solutions of both azo dyes.
p. 10387-10408
Received: 3 October 2011; in revised form: 2 November 2011 / Accepted: 16 November 2011 / Published: 15 December 2011
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| Download PDF Full-text (390 KB) Abstract: The formation of (E )-3-{2-(2,5-diphenylpyrazolo[1,5-c ]pyrimidin-7-yl)hydrazono}indolin-2-ones 3 has been achieved by condensation of equimolar amounts of 7-hydrazino-2,5-diphenylpyrazolo[1,5-c ]pyrimidine (1 ) and isatin (or isatin derivatives) 2 at room temperature. The (E )-products could be isomerized into corresponding the (Z )-3 isomers. Reactions of the latter fused heterocyclic hydrazones towards different electro-philic reagents yielded the corresponding 3-substituted derivatives 4 – 7 . Dehydrative cyclisation of the hydrazones 3 using phosphorus oxychloride afforded the 2,5-diphenyl- indolo[2,3-e ]pyrazolo[1',5':3",4"]pyrimido[2",1"-c ][1,2,4] triazines 13 . The polyfused heterocyclic ring system 13 underwent electrophilic substitution reactions at position 4 rather than at position 3. The 3-bromo isomer of 17 was prepared by a sequence of reactions starting from 2,5-diphenylpyrazolo[1,5-c ]pyrimidine-7(6H )-thione (11 ). The orientation of the electrophilic attack was supported by spectroscopic and chemical evidence. Some of the synthesized compounds were found to possess slight to moderate activity against the microorganisms Bacillus subtilis , Micrococcus luteus , Staphylococcus aureus , Escherichia coli and Pseudomonas aeruginosa .
p. 10409-10419
Received: 16 November 2011; in revised form: 3 December 2011 / Accepted: 7 December 2011 / Published: 15 December 2011
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| Download PDF Full-text (204 KB) Abstract: Simple synthesis and biological activities of modafinil derivatives are described. The key reactions include condensation of acid and propargyl alcohol, subsequent 1,3-dipolar cycloaddition reaction of alkynes and (3-azido-propyl)cyclohexane or (4-azido-butyl)benzene in the presence of sodium ascorbate and CuSO4 ·5H2 O in excellent yield. They were then evaluated for the suppression of LPS-induced NO generation in vitro . It was found that all compounds showed moderate effects for suppression of LPS-induced NO generation.
p. 10420-10432
Received: 25 October 2011; in revised form: 1 December 2011 / Accepted: 5 December 2011 / Published: 15 December 2011
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| Download PDF Full-text (207 KB) Abstract: A new series of thiadiazole-enaminones 4 were synthesized via reactions of 5-acetyl-1,3,4-thiadiazoles 3 with dimethylformamide-dimethylacetal (DMF-DMA). The simple phenyl substituted thiadiazole-enaminone 4f was used as a synthetic precursor for the preparation of a wide variety of new heterocyclic compounds, including the 5-substituted-1,3,4-thiadiazole derivatives 5 , 6 , 11 , 12 and 13 , which were obtained via reactions of 4f with nitrogen nucleophiles. Also, reactions of enaminone 4f with carbon nucleophiles afforded the respective 1,3,4-thiadiazoles 8a–d . In addition, the results of the antimicrobial activities of thiadiazole-enaminones 4 and their precursors 2 and 3 indicate that some members of this series display promising activities against all tested microorganisms.
p. 10433-10442
Received: 10 November 2011; in revised form: 27 November 2011 / Accepted: 7 December 2011 / Published: 15 December 2011
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| Download PDF Full-text (197 KB) Abstract: Oxidative stress is involved in the development and progression of otitis media (OM). In this study, we investigated the effect of Ginkgo leaf parenteral solution on blood and cochlea antioxidant and immunity indexs in OM rats. In OM model rats, blood and cochlea malondialdehyde (MDA), nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8) and interleukin-10 (IL-10) levels were significantly increased, whereas antioxidant enzymes activities (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and glutathione reductase (GR)) were significantly decreased compared with normal rats. Treatment with Ginkgo leaf parenteral solution restored the altered parameters in a dose-dependent manner. We conclude that Ginkgo leaf parenteral solution confers protection against oxidative injuries in OM rats by increasing activities of antioxidants and immunity, suggesting a potential drug for the prevention and therapy of OM.
p. 10443-10456
Received: 26 November 2011; in revised form: 2 December 2011 / Accepted: 8 December 2011 / Published: 15 December 2011
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| Download PDF Full-text (437 KB) Abstract: Agricultural wastes have great potential for the removal of heavy metal ions from aqueous solution. The contamination of water by toxic heavy metals is a worldwide environmental problem. Unlike organic pollutants, the majority of which are susceptible to biological degradation, heavy metals do not degrade into harmless end products. Discharges containing cadmium, in particular, are strictly controlled because of the highly toxic nature of this element and its tendency to accumulate in the tissues of living organisms. This work aims to develop inexpensive, highly available, effective metal ion adsorbents from natural wastes as alternatives to existing commercial adsorbents. In particular, Tamrix articulata wastes were modified chemically by esterification with maleic acid to yield a carboxyl-rich adsorbent. The adsorption behavior of treated Tamrix articulata wastes toward cadmium ions in aqueous solutions in a batch system has been studied as a function of equilibration time, adsorbent dose, temperature and pH. Results showed that the maximum adsorption capacity was 195.5 mg/g in a pH 4 solution at 30 °C with a contact time of 120 min, an initial concentration of 400 mg/L and an adsorbent dose of 0.3 g/L. The kinetic data were analyzed using pseudo-first-order and pseudo-second-order kinetic models. It was shown that the adsorption of cadmium could be described by a pseudo-second-order equation. The experimental data were also analyzed using the Langmuir and Freundlich models of adsorption. Thermodynamic parameters such as ΔGo , ΔHo and ΔSo have been evaluated and it has been found that the sorption process was spontaneous and exothermic in nature. From all of our data, we conclude that the treated Tamrix articulata wastes investigated in this study showed good potential for cadmium removal from aqueous solutions.
p. 10457-10470
Received: 14 October 2011; in revised form: 5 December 2011 / Accepted: 7 December 2011 / Published: 15 December 2011
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| Download PDF Full-text (978 KB) Abstract: The radical-scavenging activity of dietary phytophenols has been investigated by many researches due to their antioxidant, anti-inflammatory and anticancer property but the radical-scavenging effect of 2-phytophenol and the phytophenol:co-antioxidants, vitamin C and thiol combination under nearly anaerobic conditions still remains unknown. The radical-scavenging activity for seventeen phytophenols and for six synthetic phenols (positive controls) was investigated using the induction period method in the polymerization of methyl methacrylates (MMA) initiated by thermal decomposition of benzoyl peroxide (BPO) by monitoring differential scanning calorimetery (DSC). The kinh for the phytophenols was likely with the range 0.5 × 103 M−1 s−1 −2.2 × 103 M−1 s−1 , whereas that for synthetic phenols, hydroquinone and galvinoxyl, was with the range 7 × 103 M−1 s−1 −8 × 103 M−1 s−1 . Also, the additive scavenging effect of the (−)-epigallocatechin (EGC):(−)-epicatechin (EC) and the (+)-catechin:epicatechin (EC) combination was observed at 1:1 molar ratio, whereas that of the EC:quercetin combination showed the cancel (prooxidative) effect. Furthermore, the EGC:ASDB (L-ascorbyl 2,6-dibutylate) or 2-ME (2-mercaptoethanol) combination showed the prooxidative effect. Such enhancement of prooxidation in the combination may increase their toxic effects due to their cooxidation. Also, the synergic, additive or cancel effects of the flavonoid:vitamins E combination on the induction period in the BPO (a PhCOO* radical) and 2,2′-azobisisobutyronitrile (AIBN, an R* radical) systems are discussed.
p. 10471-10478
Received: 22 November 2011; in revised form: 5 December 2011 / Accepted: 12 December 2011 / Published: 16 December 2011
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| Download PDF Full-text (207 KB) Abstract: A new rosane diterpenoid, 3a-hydroxy-5,15-rosadien-11-one (3 ), was isolated, together with a known rosane diterpenoid, 5,15-rosadiene-3,11-dione (4 ), and an aromadendrane sesquiterpenoid, ent -cyclocolorenone (5 ), from the Et2 O extract of an unidentified Argentine liverwort Anastrophyllum species. Moreover, four known sesquiterpene lactones 6 –9 and two known bibenzyls 10 , 11 were isolated from the Et2 O extracts of Argentine Frullania brasiliensis and Radula voluta , respectively. The structures of compounds 3 –11 were determined by the use of NMR techniques.
(This article belongs to the Special Issue
Terpenoids )
p. 10479-10490
Received: 1 November 2011; in revised form: 1 December 2011 / Accepted: 5 December 2011 / Published: 16 December 2011
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| Download PDF Full-text (221 KB) Abstract: Chemical fractionation of the methanolic extract of leaves of Leiothrix spiralis Ruhland afforded the flavonoids luteolin-6-C -b-D-glucopyranoside (1 ), 7-methoxyluteolin-6-C -b-D-glucopyranoside (2 ), 7-methoxyluteolin-8-C -b-D-glucopyranoside (3 ), 4′-methoxyluteolin-6-C -b-D-glucopyranoside (4 ), and 6-hydroxy-7-methoxyluteolin (5 ), and the xanthones 8-carboxymethyl-1,5,6-trihydroxy-3-methoxyxanthone (6 ), 8-carboxy-methyl-1,3,5,6-tetrahydroxyxanthone (7 ). Methanolic extract, fractions, and isolated compounds of the leaves of L. spiralis were assayed against Gram-positive (Staphylococcus aureus , Bacillus subtilis and Enterococcus faecalis ) and Gram-negative bacteria (Escherichia coli , Pseudomonas aeruginosa , Salmonella setubal and Helicobacter pylori ) and fungi (the yeasts Candida albicans , C. tropicalis , C. krusei and C. parapsilosis ). We observed the best minimum inhibitory concentration values for the methanolic extract against Candida parapsilosis , for the fraction 5 + 6 against Gram-negative bacteria E. coli and P. aeruginosa , and compound 7 against all tested Candida strains. The methanolic extract contents suggest that this species may be a promising source of compounds to produce natural phytomedicines.
p. 10491-10506
Received: 17 November 2011; in revised form: 3 December 2011 / Accepted: 8 December 2011 / Published: 16 December 2011
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| Download PDF Full-text (213 KB) Abstract: The human skin, as the boundary organ between the human body and the environment, is under the constant influence of free radicals (FR), both from the outside in and from the inside out. Carotenoids are known to be powerful antioxidant substances playing an essential role in the reactions of neutralization of FR (mainly reactive oxygen species ROS). Carotenoid molecules present in the tissue are capable of neutralizing several attacks of FR, especially ROS, and are then destroyed. Human skin contains carotenoids, such as α-, γ-, β-carotene, lutein, zeaxanthin, lycopene and their isomers, which serve the living cells as a protection against oxidation. Recent studies have reported the possibility to investigate carotenoids in human skin quickly and non-invasively by spectroscopic means. Results obtained from in-vivo studies on human skin have shown that carotenoids are vital components of the antioxidative protective system of the human skin and could serve as marker substances for the overall antioxidative status. Reflecting the nutritional and stress situation of volunteers, carotenoids must be administered by means of antioxidant-rich products, e.g., in the form of fruit and vegetables. Carotenoids are degraded by stress factors of any type, inter alia , sun radiation, contact with environmental hazards, illness, etc. The kinetics of the accumulation and degradation of carotenoids in the skin have been investigated.
(This article belongs to the Special Issue
Carotenoids )
p. 10507-10540
Received: 11 November 2011; in revised form: 3 December 2011 / Accepted: 9 December 2011 / Published: 16 December 2011
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| Download PDF Full-text (327 KB) Abstract: The transdermal route of administration offers an alternative pathway for systemic drug delivery with numerous advantages over conventional routes. Regrettably, the stratum corneum forms a formidable barrier that hinders the percutaneous penetration of most drugs, offering an important protection mechanism to the organism against entrance of possible dangerous exogenous molecules. Different types of penetration enhancers have shown the potential to reversibly overcome this barrier to provide effective delivery of drugs across the skin. Although certain chemical and physical skin penetration enhancers are already employed by the pharmaceutical industry in commercially available transdermal products, some skin penetration enhancers are associated with irritating and toxic effects. This emphasizes the need for the discovery of new, safe and effective skin penetration enhancers. Penetration enhancers from natural origin have become popular as they offer several benefits over their synthetic counterparts such as sustainable mass production from a renewable resource and lower cost depending on the type of extraction used. The aim of this article is to give a comprehensive summary of the results from scientific research conducted on skin penetration enhancers of natural origin. The discussions on these natural penetration enhancers have been organized into the following chemical classes: essential oils, terpenes, fatty acids and polysaccharides.
p. 10541-10555
Received: 4 November 2011; in revised form: 5 December 2011 / Accepted: 12 December 2011 / Published: 19 December 2011
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| Download PDF Full-text (235 KB) Abstract: Biotransformation of (1S )-2-carene and (1S )-3-carene by Picea abies suspension culture led to the formation of oxygenated products. (1S )-2-Carene was transformed slowly and the final product was identified as (1S )-2-caren-4-one. On the other hand, the transformation of (1S )-3-carene was rapid and finally led to the formation of (1S )-3-caren-5-one and (1S )-2-caren-4-one as equally abundant major products. The time-course of the reaction indicates that some products abundant at the beginning of the reaction (e.g. (1S ,3S ,4R )-3,4-epoxycarane and (1R )-p -mentha-1(7),2-dien-8-ol) were consumed by a subsequent transformations. Thus, a precise selection of the biotransformation time may be used for a production of specific compounds.
(This article belongs to the Special Issue
Terpenoids )
p. 10556-10569
Received: 31 October 2011; in revised form: 25 November 2011 / Accepted: 5 December 2011 / Published: 19 December 2011
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| Download PDF Full-text (433 KB) Abstract: Non-small cell lung cancer (NSCLC) is the leading cause of cancer death worldwide. Clinical and laboratory studies have suggested that multi-targeting approaches against neoplastic cells could help to increase patient survival and might reduce the emergence of cells that are resistant to single-target inhibitors. Artesunate (ART) is one of the most potent and rapidly acting antimalarial agents known, and it also exerts a profound cytotoxic activity toward cancer cells and reverses multi-drug resistance. In the present study, we found that artesunate inhibited NSCLC A549 cell growth and proliferation, induced apoptosis and suppressed tumor growth in a dose-dependent manner in A549 cells and a mouse xenograft model. Furthermore, artesunate down-regulated the expression of epidermal growth factor receptor (EGFR), Akt and ATP-binding cassette subfamily G member 2 (ABCG2) at the mRNA and protein levels in vitro and in vivo . In conclusion, artesunate is an effective anti-cancer drug that may enhance the effectiveness of other anticancer drugs and may reverse multi-drug resistance by suppressing the transcription of ABCG2, which inhibits drug efflux.
p. 10570-10591
Received: 24 November 2011 / Accepted: 29 November 2011 / Published: 19 December 2011
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| Download PDF Full-text (1729 KB) | Abstract: Three starches from the wheat varieties AK58, ZM18 and YZ4110 were separated into large (A) and small (B) granules, which were characterized structurally and evaluated for their functional properties. SEM results showed that the size of A-granules from ZM18 and YZ4110 were about the same, but the sizes of A-granules and B-granules from AK58 were larger than those of ZM18 and YZ4110. FTIR spectra showed that all the samples exhibited a similar pattern, with seven main modes with maximum absorbance peaks near 3,500, 3,000, 1,600, 1,400, 1,000, 800, 500 cm−1 . The B-granules of ZM18 and YZ4110 had less amylose content, although the difference among the total amylose contents of the three unfractionated starches was not significant. X-ray diffraction (XRD) patterns showed predominantly A-type crystallinity for all the starches. The A-granules showed sharper XRD patterns than the other starches. DSC analysis showed that the A-granules had broader ranges of gelatinization temperatures than the B-granules from the same wheat variety. The gelatinization enthalpy (ΔH) of A-granules was higher than that of B-granules. AK58 exhibited the smallest enthalpy, while ZM18 showed the largest enthalpy. In pasting tests, the A-granule starch of AK58 had higher peak, final and setback viscosity, lower breakdown and pasting temperature, and the B-granule starch and unfractionated starch of AK58 had lower peak, breakdown, final and setback viscosity and higher pasting temperature than ZM18 and YZ4110.
p. 10592-10603
Received: 3 October 2011; in revised form: 23 November 2011 / Accepted: 2 December 2011 / Published: 19 December 2011
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| Download PDF Full-text (258 KB) Abstract: In this work, an evaluation of the biological activities of Globularia alypum L. extracts and their global chemical composition was realized. Extracts from G. alypum were obtained by two extraction methods. The composition of polyphenols (8.5–139.95 g gallic acid equivalent/Kg of dry mass), tannins (1.39–18.65 g catechin equivalent/Kg of dry mass), anthocyanins (8.17–70.69 mg cyanidin equivalent/Kg of dry mass) and flavonoids (0.31–19.28 g quercetin equivalent/Kg of dry mass) was evaluated. The samples were subjected to a screening for their antioxidant activities using the DPPH· and ABTS· + assays. For the first time, the anti-tuberculosis activity (H37 Rv) for G. alypum was tested against Mycobacterium tuberculosis . The strongest antioxidant activity was obtained for the methanol extract (IC50 = 15.58 ± 0.168 mg/L) and the best anti-tuberculosis activity was obtained for the petroleum ether extract (IC50 = 77 mg/L). We have found a positive correlation between the total phenolics content and the antioxidant activity R2 = 0.88 (DPPH· ) and R2 = 0.97 (ABTS· + ). We have found also a positive correlation between the flavonoid content and the antioxidant activity R2 = 0.91 (DPPH· ) and R2 = 0.91 (ABTS· + ).
p. 10604-10618
Received: 13 November 2011; in revised form: 2 December 2011 / Accepted: 12 December 2011 / Published: 19 December 2011
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| Download PDF Full-text (283 KB) Abstract: This work reviews the production of terpenoids by endophytic fungi and their biological activities, in period of 2006 to 2010. Sixty five sesquiterpenes, 45 diterpenes, five meroterpenes and 12 other terpenes, amounting to 127 terpenoids were isolated from endophytic fungi.
(This article belongs to the Special Issue
Terpenoids )
p. 10619-10630
Received: 25 October 2011; in revised form: 9 December 2011 / Accepted: 16 December 2011 / Published: 19 December 2011
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| Download PDF Full-text (465 KB) Abstract: Panax ginseng has long been used in Asia as a herbal medicine for the prevention and treatment of various diseases, including cancer. The current study evaluated the cytotoxic potency against a variety of cancer cells by using ginseng ethanol extracts (RSE), protopanaxadiol (PPD)-type, protopanaxatriol (PPT)-type ginsenosides fractions, and their hydrolysates, which were prepared by stepwise hydrolysis of the sugar moieties of the ginsenosides. The results showed that the cytotoxic potency of the hydrolysates of RSE and total PPD-type or PPT-type ginsenoside fractions was much stronger than the original RSE and ginsenosides; especially the hydrolysate of PPD-type ginsenoside fractions. Subsequently, two derivatives of protopanaxadiol (1 ), compounds 2 and 3 , were synthesized via hydrogenation and dehydration reactions of compound 1 . Using those two derivatives and the original ginsenosides, a comparative study on various cancer cell lines was conducted; the results demonstrated that the cytotoxic potency was generally in the descending order of compound 3 > 20(S )-dihydroprotopanaxadiol (2 ) > PPD (1 ) > 20(S )-Rh2 > 20(R )-Rh2 ≈ 20(R )-Rg3 ≈ 20(S )-Rg3. The results clearly indicate the structure-related activities in which the compound with less polar chemical structures possesses higher cytotoxic activity towards cancer cells.
p. 10631-10644
Received: 16 November 2011; in revised form: 2 December 2011 / Accepted: 9 December 2011 / Published: 19 December 2011
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| Download PDF Full-text (203 KB) | Abstract: The effects of the oligosaccharides from the endophytic fungus Fusarium oxysporum Dzf17 as elicitors on diosgenin production in cell suspension cultures of its host Dioscorea zingiberensis were investigated. Three oligosaccharides, DP4, DP7 and DP10, were purified from the oligosaccharide fractions DP2-5, DP5-8 and DP8-12, respectively, which were prepared from the water-extracted mycelial polysaccharide of the endophytic fungus F. oxysporum Dzf17. When the cell cultures were treated with fraction DP5-8 at 20 mg/L on day 26 and harvested on day 32, the maximum diosgenin yield (2.187 mg/L) was achieved, which was 5.65-fold of control (0.387 mg/L). When oligosaccharides DP4, DP7 and DP10 were individually added to 26-day-old D. zingiberensis cell cultures at concentrations of 2, 4, 6, 8 and 10 mg/L in medium, DP7 at 6 mg/L was found to significantly enhance diosgenin production, with a yield of 3.202 mg/L, which was 8.27-fold of control. When the cell cultures were treated with DP7 twice on days 24 and 26, and harvested on day 30, both diosgenin content and yield were significantly increased and reached the maximums of 1.159 mg/g dw and 4.843 mg/L, both of which were higher than those of single elicitation, and were 9.19- and 12.38-fold of control, respectively.
p. 10645-10652
Received: 22 November 2011; in revised form: 9 December 2011 / Accepted: 16 December 2011 / Published: 19 December 2011
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| Download PDF Full-text (262 KB) Abstract: Two samples of Cremanthodium stenactinium (Asteraceae) were collected in Sichuan Province, China. From the ethyl acetate extracts of the roots, three new eremophilane-type sesquiterpenoids and one new trinoreremophilane compound were isolated, together with other known eremophilanes. Their structures were determined based on the spectroscopic data. This is the first report of isolation of eremophilane-type compounds from the genus Cremanthodium .
(This article belongs to the Special Issue
Terpenoids )
p. 10653-10667
Received: 11 November 2011; in revised form: 25 November 2011 / Accepted: 7 December 2011 / Published: 20 December 2011
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| Download PDF Full-text (501 KB) Abstract: Seventeen diterpenes belonging to the labdane, abietane and isopimarane skeleton classes were isolated from the resin of the Chilean gymnosperm Austrocedrus chilensis and identified by spectroscopic and spectrometric methods. The diterpene 12-oxo-labda-8(17),13E -dien-19 oic acid is reported for the first time as a natural product and 14 diterpenes are reported for the first time for the species.
p. 10668-10684
Received: 5 October 2011; in revised form: 6 December 2011 / Accepted: 16 December 2011 / Published: 20 December 2011
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| Download PDF Full-text (257 KB) Abstract: We present an efficient procedure for the synthesis of thirty-six N 1 ,N 4 -substituted thiosemicarbazones, including twenty-five ones that are reported for the first time, using a microwave-assisted methodology for the reaction of thiosemicarbazide intermediates with aldehydes in the presence of glacial acetic acid in ethanol and under solvent free conditions. Overall reaction times (20–40 min when ethanol as solvent, and 3 min under solvent free conditions) were much shorter than with the traditional procedure (480 min); satisfactory yields and high-purity compounds were obtained. The thiosemicarbazide intermediates were obtained from alkyl or aryl isothiocyanates and hydrazine hydrate or phenyl hydrazine by stirring at room temperature for 60 min or by microwave irradiation for 30 min, with lower yields for the latter. The preliminary in vitro antifungal activity of thiosemicarbazones was evaluated against Aspergillus parasiticus and Candida albicans .
p. 10685-10694
Received: 20 November 2011; in revised form: 2 December 2011 / Accepted: 13 December 2011 / Published: 20 December 2011
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| Download PDF Full-text (364 KB) Abstract: In a cell-based screen of novel anticancer agents, the hit compound 1a which bears a pyrazolo[3,4-d ]pyrimidine scaffold exhibited high inhibitory activity against a panel of four different types of tumor cell lines. In particular, the IC50 for A549 cells was 2.24 µM, compared with an IC50 of 9.20 µM for doxorubicin, the positive control. Four synthetic routes of the key intermediate 3 of 1a were explored and 1a was prepared via route D on the gram scale for further research. Two analogs of 1a were synthesized and their preliminary structure-activity relationships were studied. Flow cytometric analysis revealed that compound 1a could significantly induce apoptosis in A549 cells in vitro at low micromolar concentrations. These results suggest that the target compound 1a and its analogs with the pyrazolo[3,4-d ]pyrimidine scaffold might potentially constitute a novel class of anticancer agents, which requires further studies.
p. 10695-10708
Received: 1 November 2011; in revised form: 9 December 2011 / Accepted: 13 December 2011 / Published: 20 December 2011
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| Download PDF Full-text (503 KB) | Abstract: Double-stranded DNA (dsDNA) templates can hybridize to and accelerate cleavage of oligonucleotides containing a P3’→N5’ phosphoramidate (P-N) linkage. This dsDNA-templated cleavage of P-N linkages could be due to conformational strain placed on the linkage upon triplex formation. To determine whether duplex formation also induced conformational strain, we examined the reactivity of the oligonucleotides with a P-N linkage in the presence of single-stranded templates, and compared these reactions to those with dsDNA templates. P-N oligonucleotides that are cleaved upon duplex formation could be used as probes to detect single-stranded nucleic acids.
p. 10709-10721
Received: 4 November 2011; in revised form: 6 December 2011 / Accepted: 13 December 2011 / Published: 20 December 2011
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| Download PDF Full-text (417 KB) Abstract: A disintegrin and metalloprotease with thrombospondin type I motifs-1 (ADAMTS1) plays a crucial role in inflammatory joint diseases and its inhibitors are potential candidates for anti-arthritis drugs. For the purposes of drug discovery, we reported the development and validation of fluorescence resonance energy transfer (FRET) assay for high-throughput screening (HTS) of the ADAMTS1 inhibitors. A FRET substrate was designed for a quantitative assay of ADAMTS1 activity and enzyme kinetics studies. The assay was developed into a 50-µL, 384-well assay format for high throughput screening of ADAMTS1 inhibitors with an overall Z’ factor of 0.89. ADAMTS1 inhibitors were screened against a diverse library of 40,960 total compounds with the established HTS system. Four structurally related hits, naturally occurring compounds, kuwanon P, kuwanon X, albafuran C and mulberrofuran J, extracted from the Chinese herb Morus alba L., were identified for further investigation. The results suggest that this FRET assay is an excellent tool, not only for measurement of ADAMTS1 activity but also for discovery of novel ADAMTS1 inhibitors with HTS.
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