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Special Issue "Antioxidants 2012"

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A special issue of Molecules (ISSN 1420-3049).

Deadline for manuscript submissions: closed (30 November 2012)

Special Issue Editor

Guest Editor
Dr. Dejian Huang (Website)

Food Science & Technology Programme, c/o Department of Chemistry, 3 Science Drive 3, Faculty of Science, National University of Singapore, 117543 Singapore
Fax: +65 6775 7895
Interests: fabrication of quantum dots; transition metal complex; polyphenolic compounds; antioxidant; pro-oxidant activity

Special Issue Information

Dear Colleagues,

Mounting evidence suggests that oxidative stress is the causative factor for chronic diseases including cardiovascular diseases, cancer, diabetes, neurodegenerative diseases and ageing. Preventing these chronic diseases through antioxidants (or radical scavengers) has been a very attractive idea as evidenced by the large amount of scholarly articles published. As a result, the notion that dietary antioxidant are beneficial to our health is widely accepted in general public. Scientifically, the action mechanisms of antioxidant are much more complex and remain to be a hotly pursued research field.  Antioxidants may work as oxidase (e.g. lipoxygenases and cyclooxygenase) inhibitor, transition metal chelators (preventing Fenton reaction), and scavengers of wide range of biologically relevant reactive oxygen species including superoxide, peroxyl radicals, hypochlorite, peroxynitrite and nitrogen dioxide, and singlet oxygen. In this special issue on “antioxidants” the contributions may cover chemical, cell line, and in vivo protocols or methods in evaluation of antioxidant activity against  oxidants or oxidative stress; chemical synthesis of novel antioxidant compounds and their activity and action mechanisms; extraction, isolation and structural characterization of dietary antioxidants from natural resources; activity and mechanisms of antioxidants in chemical, food, and biological models; replacement of synthetic radical scavengers (e.g. BHT) by naturally occurring antioxidants; digestion, absorption, and metabolism of dietary antioxidants in animal model and human study; efficacy of antioxidants in mitigating oxidative stress status in human clinical trials.

Dr. Dejian Huang
Guest Editor

Keywords

•    bioactivity
•    antioxidants
•    radical scavengers
•    analytical methods
•    structure elucidation
•    mechanism of action
•    oxidative stress
•    natural products

Published Papers (27 papers)

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Open AccessArticle Superoxide Scavenging Effects of Some Novel Bis-Ligands and Their Solvated Metal Complexes Prepared by the Reaction of Ligands with Aluminum, Copper and Lanthanum Ions
Molecules 2013, 18(6), 6128-6141; doi:10.3390/molecules18066128
Received: 4 March 2013 / Revised: 20 May 2013 / Accepted: 20 May 2013 / Published: 23 May 2013
Cited by 3 | PDF Full-text (705 KB) | HTML Full-text | XML Full-text
Abstract
Novel antioxidants have been synthesized and characterized by their chemical properties as antioxidants with high superoxide scavenging activity. (2R,3R)-diphenylethylenediamine is a spacer in antioxidants, and we synthesized targets 11a and 11b by conjugation with o-hydroquinone and p [...] Read more.
Novel antioxidants have been synthesized and characterized by their chemical properties as antioxidants with high superoxide scavenging activity. (2R,3R)-diphenylethylenediamine is a spacer in antioxidants, and we synthesized targets 11a and 11b by conjugation with o-hydroquinone and p-hydroquinone at the two N-termini, respectively. Superoxide scavenging activities of the plant flavonoid-like 11a and 11b were compared with those of known antioxidants, and shown to increase in the following order: curcumin << ascorbic acid < Trolox < ()-epicatechin < 11a < quercetin ≤ 11b . Compound 11a also formed a solvated 11a–metal complex with metal ions. The 11a–Cu2+ complex was shown to have higher superoxide scavenging activity than that of 11a, 11b, Cu2+, and the 11a–Al3+ and 11a–La3+ complexes, whereas the 11a–Al3+ complex increased rather than decreased superoxide levels. The 11a–Al3+ complex did not abstract one electron from the SOMO of O2−. since the HOMO and LUMO phases of Al3+ do not exist in the center of the 11a–Al3+ complex. However, the SOMO of the 11a–Cu2+ complex distributed in the center of Cu2+ may abstract one electron from the SOMO of O2−.. These results suggest that 11a and 11b are powerful antioxidants. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle The Ameliorative Effects of L-2-Oxothiazolidine-4-Carboxylate on Acetaminophen-Induced Hepatotoxicity in Mice
Molecules 2013, 18(3), 3467-3478; doi:10.3390/molecules18033467
Received: 23 January 2013 / Revised: 31 January 2013 / Accepted: 14 March 2013 / Published: 18 March 2013
Cited by 7 | PDF Full-text (1658 KB) | HTML Full-text | XML Full-text
Abstract
The aim of the study was to investigate the ameliorative effects and the mechanism of action of L-2-oxothiazolidine-4-carboxylate (OTC) on acetaminophen (APAP)-induced hepatotoxicity in mice. Mice were randomly divided into six groups: normal control group, APAP only treated group, APAP + 25 [...] Read more.
The aim of the study was to investigate the ameliorative effects and the mechanism of action of L-2-oxothiazolidine-4-carboxylate (OTC) on acetaminophen (APAP)-induced hepatotoxicity in mice. Mice were randomly divided into six groups: normal control group, APAP only treated group, APAP + 25 mg/kg OTC, APAP + 50 mg/kg OTC, APAP + 100 mg/kg OTC, and APAP + 100 mg/kg N-acetylcysteine (NAC) as a reference control group. OTC treatment significantly reduced serum alanine aminotransferase and aspartate aminotransferase levels in a dose dependent manner. OTC treatment was markedly increased glutathione (GSH) production and glutathione peroxidase (GSH-px) activity in a dose dependent manner. The contents of malondialdehyde and 4-hydroxynonenal in liver tissues were significantly decreased by administration of OTC and the inhibitory effect of OTC was similar to that of NAC. Moreover, OTC treatment on APAP-induced hepatotoxicity significantly reduced the formation of nitrotyrosin and terminal deoxynucleotidyl transferase dUTP nick end labeling positive areas of liver tissues in a dose dependent manner. Furthermore, the activity of caspase-3 in liver tissues was reduced by administration of OTC in a dose dependent manner. The ameliorative effects of OTC on APAP-induced liver damage in mice was similar to that of NAC. These results suggest that OTC has ameliorative effects on APAP-induced hepatotoxicity in mice through anti-oxidative stress and anti-apoptotic processes. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Differences in the Phenolic Composition and Antioxidant Properties between Vitis coignetiae and Vitis vinifera Seeds Extracts
Molecules 2013, 18(3), 3410-3426; doi:10.3390/molecules18033410
Received: 30 November 2012 / Revised: 8 March 2013 / Accepted: 12 March 2013 / Published: 14 March 2013
Cited by 10 | PDF Full-text (302 KB) | HTML Full-text | XML Full-text
Abstract
Phenolic compounds were extracted from European and Japanese grapevine species (Vitis vinifera and V. coignetiae) seeds using 80% methanol or 80% acetone. The total content of phenolic compounds was determined utilizing Folin-Ciocalteu’s phenol reagent, while the content of tannins was [...] Read more.
Phenolic compounds were extracted from European and Japanese grapevine species (Vitis vinifera and V. coignetiae) seeds using 80% methanol or 80% acetone. The total content of phenolic compounds was determined utilizing Folin-Ciocalteu’s phenol reagent, while the content of tannins was assayed by the vanillin and BSA precipitation methods. Additionally, the DPPH free radical and ABTS cation radical scavenging activities and the reduction power of the extracts were measured. The HPLC method was applied to determine the phenolic compounds, such as phenolic acids and catechins. The seeds contained large amounts of tannins and gallic acid and observable quantities of catechins, p-coumaric, ferulic and caffeic acids. The dominant form of phenolic acids in the extracts was the ester-bound form. The content of total phenolics was higher in the European grape V. vinifera seeds, which also contained more tannins, catechins and phenolic acids, except for caffeic acid. Extracts from V. vinifera seeds showed better radical scavenger properties and stronger reducing power. The total contents of phenolic compounds and tannins in acetone extracts were higher than in methanolic extracts. Acetone extracts also exhibited stronger antiradical properties as well as stronger reducing power. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Antioxidant Activity of Extracts of Momordica Foetida Schumach. et Thonn.
Molecules 2013, 18(3), 3241-3249; doi:10.3390/molecules18033241
Received: 31 December 2012 / Revised: 16 January 2013 / Accepted: 6 March 2013 / Published: 13 March 2013
Cited by 2 | PDF Full-text (340 KB) | HTML Full-text | XML Full-text
Abstract
Momordica foetida Schumach. et Thonn. (Cucurbitaceae) is a perennial climbing herb with tendrils, found in swampy areas in Central Uganda. Antidiabetic and antilipogenic activities were reported for some Momordica species, however the mechanism of action is still unknown. Oxidative stress may represent [...] Read more.
Momordica foetida Schumach. et Thonn. (Cucurbitaceae) is a perennial climbing herb with tendrils, found in swampy areas in Central Uganda. Antidiabetic and antilipogenic activities were reported for some Momordica species, however the mechanism of action is still unknown. Oxidative stress may represent an important pathogenic mechanism in obesity-associated metabolic syndrome. The present study evaluated free radical scavenging capacity of different concentrations of aqueous, methanolic and dichloromethane leaf extracts of Momordica foetida Schumach. et Thonn. and the ability of these extracts to inhibit in vitro plasma lipid peroxidation; in addition, healthy human adipose mesenchymal stem cell cultures were used in order to test the hypothesis that these extracts may affect adipocyte differentiation. Results obtained in this study suggested that aqueous extract might be useful in preventing metabolic syndrome. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Antioxidant Activity of the Extracts of Some Cowpea (Vigna unguiculata (L) Walp.) Cultivars Commonly Consumed in Pakistan
Molecules 2013, 18(2), 2005-2017; doi:10.3390/molecules18022005
Received: 23 November 2012 / Revised: 28 January 2013 / Accepted: 31 January 2013 / Published: 5 February 2013
Cited by 16 | PDF Full-text (277 KB)
Abstract
The present investigation has been carried out to determine the antioxidant activity of the methanolic extracts obtained from four cultivars of cowpea (Vigna unguiculata (L) Walp.) seeds. Phenolic compounds present in the extracts showed the antioxidant and antiradical properties when investigated [...] Read more.
The present investigation has been carried out to determine the antioxidant activity of the methanolic extracts obtained from four cultivars of cowpea (Vigna unguiculata (L) Walp.) seeds. Phenolic compounds present in the extracts showed the antioxidant and antiradical properties when investigated using a linoleic acid peroxidation model, FRAP, ORAC and TRAP assays, as well as DPPH, hydroxyl, nitric oxide and superoxide radical scavenging activity. The HPLC analysis of the cowpea extracts showed the presence of neochlorogenic acid, chlorogenic acid and caffeic acids. The results indicated that methanolic extract of the cowpea resembled in the aforementioned activities those from other leguminous seeds and pulses. Phenolic constituents contained in cowpea may have a future role as ingredients in the development of functional foods. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Study of Total Antioxidant Activity of Human Serum Blood in the Pathology of Alcoholism
Molecules 2013, 18(2), 1811-1818; doi:10.3390/molecules18021811
Received: 28 November 2012 / Revised: 10 January 2013 / Accepted: 15 January 2013 / Published: 30 January 2013
Cited by 3 | PDF Full-text (220 KB)
Abstract
The total antioxidant activity (TAA) of human serum blood of patients suffering from alcoholism was tested by cathode voltammetry with a model process of oxygen electroreduction. A known spectrophotometrical method was used for comparison. As results the total antioxidant activity of serum [...] Read more.
The total antioxidant activity (TAA) of human serum blood of patients suffering from alcoholism was tested by cathode voltammetry with a model process of oxygen electroreduction. A known spectrophotometrical method was used for comparison. As results the total antioxidant activity of serum blood of patients with alcoholism was estimated by voltammetry during therapy in hospital. It was shown the TAA of serum blood of patients in pathology before and after treatment is lower than that one of healthy people. However, during the process of 10 days of alcoholism treatment the TAA coefficient increases. The relationship between the coefficient of total antioxidant activity of human serum blood and the stage of treatment was detected. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Antioxidant and Antimicrobial Activities of 7-Hydroxy-calamenene-Rich Essential Oils from Croton cajucara Benth.
Molecules 2013, 18(1), 1128-1137; doi:10.3390/molecules18011128
Received: 29 November 2012 / Revised: 4 January 2013 / Accepted: 11 January 2013 / Published: 16 January 2013
Cited by 9 | PDF Full-text (199 KB)
Abstract
Croton cajucara is a shrub native to the Amazon region locally known as “sacaca”. Two morphotypes are known: white and red “sacaca”. The essential oils (EO) obtained by hydrodistillation from leaves of the red morphotype were, in general, rich in 7-hydroxycalamenene (28.4%–37.5%). [...] Read more.
Croton cajucara is a shrub native to the Amazon region locally known as “sacaca”. Two morphotypes are known: white and red “sacaca”. The essential oils (EO) obtained by hydrodistillation from leaves of the red morphotype were, in general, rich in 7-hydroxycalamenene (28.4%–37.5%). The effectiveness of these EO regarding the antimicrobial activity against pathogenic microorganisms was initially investigated by the drop test method, showing significant inhibition zones. Among the microorganisms tested, the essential oils rich in 7-hydroxycalamenene were more effective against methicillin resistant Staphylococcus aureus (MRSA), Enterococcus faecalis, Mycobacterium tuberculosis, M. smegmatis, Mucor circinelloides and Rhizopus oryzae. The minimum inhibitory concentrations (MIC) of the oils were determined using the broth dilution assay. It was possible to observe that 7-hydroxycalamenene-rich oils presented high antimicrobial activity, with MIC of 4.76 × 10−3 μg/mL for MRSA, 4.88 μg/mL for M. tuberculosis, 39.06 μg/mL for M. smegmatis, and 0.152 μg/mL for R. oryzae and 3.63 × 10−8 μg/mL for M. circinelloides. The antioxidant activity of this EO suggests that 7-hydroxycalamenene provides more antioxidant activity according with EC50 less than 63.59 μg/mL. Considering the bioactive potential of EOs and 7-hydroxycalamenene could be of great interest for development of antimicrobials for therapeutic use in treatment of bacterial and fungal infections in humans and/or veterinary practice. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Sulfation and Enhanced Antioxidant Capacity of an Exopolysaccharide Produced by the Medicinal Fungus Cordyceps sinensis
Molecules 2013, 18(1), 167-177; doi:10.3390/molecules18010167
Received: 22 November 2012 / Revised: 10 December 2012 / Accepted: 19 December 2012 / Published: 24 December 2012
Cited by 11 | PDF Full-text (215 KB)
Abstract
EPS-1 was an exopolysaccharide produced by the medicinal fungus Cordyceps sinensis (Cs-HK1). In the present study, EPS-1 was sulfated with chlorosulfonic acid (CSA)-pyridine (Pyr) at different volume ratios, yielding four sulfated derivatives, SEPS-1A, B, C and D, with different degrees of substitution [...] Read more.
EPS-1 was an exopolysaccharide produced by the medicinal fungus Cordyceps sinensis (Cs-HK1). In the present study, EPS-1 was sulfated with chlorosulfonic acid (CSA)-pyridine (Pyr) at different volume ratios, yielding four sulfated derivatives, SEPS-1A, B, C and D, with different degrees of substitution (DS: 0.25–1.38) and molecular weights (17.1–4.1 kDa). The sulfation of EPS-1 occurred most frequently at the C-6 hydroxyl groups due to their higher reactivity. In aqueous solution, the native EPS-1 formed random coils or aggregated networks, but the sulfated derivatives formed single helices. The antioxidant activities of the sulfated EPS-1 derivatives for scavenging hydroxyl radicals (•OH) and 2,2-azinobis-3-ehtylbenzothiazolin-6-sulfonic acid radicals (ABTS•+) were significantly increased with increasing DS and decreasing molecular weight (MW). Sulfation has thus been shown to be an effective and favorable strategy for improving the physico-chemical properties and bioactivities of fungal polysaccharides. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Stability and Antioxidant Activity of Semi-synthetic Derivatives of 4-Nerolidylcatechol
Molecules 2013, 18(1), 178-189; doi:10.3390/molecules18010178
Received: 26 October 2012 / Revised: 16 November 2012 / Accepted: 20 November 2012 / Published: 24 December 2012
Cited by 7 | PDF Full-text (294 KB)
Abstract
4-nerolidylcatechol (4-NC) is an unstable natural product that exhibits important antioxidant, anti-inflammatory and other properties. It is readily obtainable on a multi-gram scale through straightforward solvent extraction of the roots of cultivated Piper peltatum or P. umbellatum, followed by column chromatography [...] Read more.
4-nerolidylcatechol (4-NC) is an unstable natural product that exhibits important antioxidant, anti-inflammatory and other properties. It is readily obtainable on a multi-gram scale through straightforward solvent extraction of the roots of cultivated Piper peltatum or P. umbellatum, followed by column chromatography on the resulting extract. Semi-synthetic derivatives of 4-NC with one or two substituent groups (methyl, acetyl, benzyl, benzoyl) on the O atoms have been introduced that have increased stability compared to 4-NC and significant in vitro inhibitory activity against the human malaria parasite Plasmodium falciparum. Antioxidant and anti-inflammatory properties may be important for the antiplasmodial mode of action of 4-NC derivatives. Thus, we decided to investigate the antioxidant properties, cytotoxicity and stability of 4-NC derivatives as a means to explore the potential utility of these compounds. 4-NC showed high antioxidant activity in the DPPH and ABTS assays and in 3T3-L1 cells (mouse embryonic fibroblast), however 4-NC was more cytotoxic (IC50 = 31.4 µM) and more unstable than its derivatives and lost more than 80% of its antioxidant activity upon storage in solution at −20 °C for 30 days. DMSO solutions of mono-O-substituted derivatives of 4-NC exhibited antioxidant activity and radical scavenging activity in the DPPH and ABTS assays that was comparable to that of BHA and BHT. In the cell-based antioxidant model, most DMSO solutions of derivatives of 4-NC were less active on day 1 than 4-NC, quercetin and BHA and more active antioxidants than BHT. After storage for 30 days at −20 °C, DMSO solutions of most of the derivatives of 4-NC were more stable and exhibited more antioxidant activity than 4-NC, quercetin and BHA and exhibited comparable antioxidant activity to BHT. These findings point to the potential of derivatives of 4-NC as antioxidant compounds. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Synthesis and Antiradical/Antioxidant Activities of Caffeic Acid Phenethyl Ester and Its Related Propionic, Acetic, and Benzoic Acid Analoguesc
Molecules 2012, 17(12), 14637-14650; doi:10.3390/molecules171214637
Received: 25 October 2012 / Revised: 9 November 2012 / Accepted: 5 December 2012 / Published: 10 December 2012
Cited by 14 | 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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Antioxidants 2012)
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Open AccessArticle Food Ingredient Extracts of Cyclopia subternata (Honeybush): Variation in Phenolic Composition and Antioxidant Capacity
Molecules 2012, 17(12), 14602-14624; doi:10.3390/molecules171214602
Received: 16 November 2012 / Revised: 26 November 2012 / Accepted: 5 December 2012 / Published: 7 December 2012
Cited by 24 | 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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle In Vitro Antioxidant Activities of Three Red Wine Polyphenols and Their Mixtures: An Interaction Study
Molecules 2012, 17(12), 14336-14348; doi:10.3390/molecules171214336
Received: 21 September 2012 / Revised: 7 November 2012 / Accepted: 13 November 2012 / Published: 3 December 2012
Cited by 12 | 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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Red Ginseng Marc Oil Inhibits iNOS and COX-2 via NFκB and p38 Pathways in LPS-Stimulated RAW 264.7 Macrophages
Molecules 2012, 17(12), 13769-13786; doi:10.3390/molecules171213769
Received: 11 October 2012 / Revised: 19 November 2012 / Accepted: 20 November 2012 / Published: 22 November 2012
Cited by 16 | PDF Full-text (443 KB) | HTML Full-text | 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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle α-Lipoic Acid Reduces Hypertension and Increases Baroreflex Sensitivity in Renovascular Hypertensive Rats
Molecules 2012, 17(11), 13357-13367; doi:10.3390/molecules171113357
Received: 13 September 2012 / Revised: 26 October 2012 / Accepted: 31 October 2012 / Published: 9 November 2012
Cited by 12 | PDF Full-text (266 KB)
Abstract
Renovascular hypertension has robust effects on control of blood pressure, including an impairment in baroreflex mechanisms, which involves oxidative stress. Although α-lipoic acid (LA) has been described as a potent antioxidant, its effect on renovascular hypertension and baroreflex sensitivity (BRS) has not [...] Read more.
Renovascular hypertension has robust effects on control of blood pressure, including an impairment in baroreflex mechanisms, which involves oxidative stress. Although α-lipoic acid (LA) has been described as a potent antioxidant, its effect on renovascular hypertension and baroreflex sensitivity (BRS) has not been investigated. In the present study we analyzed the effects caused by chronic treatment with LA on blood pressure, heart rate and baroreflex sensitivity (sympathetic and parasympathetic components) in renovascular hypertensive rats. Male Wistar rats underwent 2-Kidney-1-Clip (2K1C) or sham surgery and were maintained untouched for four weeks to develop hypertension. Four weeks post-surgery, rats were treated with LA (60 mg/kg) or saline for 14 days orally. On the 15th day mean arterial pressure (MAP) and heart rate (HR) were recorded. In addition, baroreflex sensitivity test using phenylephrine (8 µg/kg, i.v.) and sodium nitroprusside (25 µg/kg, i.v.) was performed. Chronic treatment with LA decreased blood pressure in hypertensive animals; however, no significant changes in baseline HR were observed. Regarding baroreflex, LA treatment increased the sensitivity of both the sympathetic and parasympathetic components. All parameters studied were not affected by treatment with LA in normotensive animals. Our data suggest that chronic treatment with LA promotes antihypertensive effect and improves baroreflex sensitivity in rats with renovascular hypertension. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle In Vitro Antioxidant Effects of Aloe barbadensis Miller Extracts and the Potential Role of These Extracts as Antidiabetic and Antilipidemic Agents on Streptozotocin-Induced Type 2 Diabetic Model Rats
Molecules 2012, 17(11), 12851-12867; doi:10.3390/molecules171112851
Received: 27 August 2012 / Revised: 2 September 2012 / Accepted: 21 September 2012 / Published: 1 November 2012
Cited by 12 | PDF Full-text (265 KB) | HTML Full-text | XML Full-text
Abstract
In this study, the total phenolic and flavonoid contents, the 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging ability and the ferric reducing power (FRAP) of Aloe vera were measured to determine the antioxidant activity of this species. The in vivo antidiabetic effects of the [...] Read more.
In this study, the total phenolic and flavonoid contents, the 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging ability and the ferric reducing power (FRAP) of Aloe vera were measured to determine the antioxidant activity of this species. The in vivo antidiabetic effects of the plant were also investigated using streptozotocin-induced type 2 diabetic model rats that were divided into five groups based on the treatment received: (1) water (WC); (2) glibenclamide; (3) concentrated gel extract (Gel-C); (4) ethanol (80%) gel extract (Gel-Et); and (5) ethanol (80%) skin extract of Aloe vera (Skin-Et). Skin-Et, which contained the highest level of total phenolics (62.37 ± 1.34 mggallic acid/kg) and flavonoids (20.83 ± 0.77 mg/kg), exhibited the highest scavenging activity (85.01 ± 0.52%) and the greatest reducing power (185.98 ± 0.41 µM), indicating that the skin contained the highest level of antioxidants. The oral consumption of Gel-Et for 4 weeks a caused significant reduction in the fasting serum glucose levels of the rats. The rats in the Gel-C-, Gel-Et- and Skin-Et-treated groups experienced a reduction in their total cholesterol levels by 11%, 17% and 25%, respectively and a reduction in their LDL cholesterol levels by 45%, 3% and 69%, respectively. The in vivo experimental antioxidant parameter MDA is strongly correlated with the in vitro antioxidant parameters of flavonoids and polyphenols, namely the DPPH and FRAP values (r = 0.94, 0.92, 0.93, 0.90), thus confirming the antioxidant potential of the Aloe vera extracts. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Evaluation of Deoxyribonucleic Acid Toxicity Induced by the Radiopharmaceutical 99mTechnetium-Methylenediphosphonic Acid and by Stannous Chloride in Wistar Rats
Molecules 2012, 17(11), 12974-12983; doi:10.3390/molecules171112974
Received: 25 September 2012 / Revised: 10 October 2012 / Accepted: 25 October 2012 / Published: 1 November 2012
Cited by 3 | PDF Full-text (203 KB) | HTML Full-text | XML Full-text
Abstract
Radiopharmaceuticals are employed in patient diagnostics and disease treatments. Concerning the diagnosis aspect, technetium-99m (99mTc) is utilized to label radiopharmaceuticals for single photon computed emission tomography (SPECT) due to its physical and chemical characteristics. 99mTc fixation on pharmaceuticals depends [...] Read more.
Radiopharmaceuticals are employed in patient diagnostics and disease treatments. Concerning the diagnosis aspect, technetium-99m (99mTc) is utilized to label radiopharmaceuticals for single photon computed emission tomography (SPECT) due to its physical and chemical characteristics. 99mTc fixation on pharmaceuticals depends on a reducing agent, stannous chloride (SnCl2) being the most widely-utilized. The genotoxic, clastogenic and anegenic properties of the 99mTc-MDP(methylene diphosphonate used for bone SPECT) and SnCl2 were evaluated in Wistar rat blood cells using the Comet assay and micronucleus test. The experimental approach was to endovenously administer NaCl 0.9% (negative control), cyclophosphamide 50 mg/kg b.w. (positive control), SnCl2 500 μg/mL or 99mTc-MDP to animals and blood samples taken immediately before the injection, 3, and 24 h after (in the Comet assay) and 36 h after, for micronucleus test. The data showed that both SnCl2 and 99mTc-MDP-induced deoxyribonucleic acid (DNA) strand breaks in rat total blood cells, suggesting genotoxic potential. The 99mTc-MDP was not able to induce a significant DNA strand breaks increase in in vivo assays. Taken together, the data presented here points to the formation of a complex between SnCl2 in the radiopharmaceutical 99mTc-MDP, responsible for the decrease in cell damage, compared to both isolated chemical agents. These findings are important for the practice of nuclear medicine. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Preparation, Characterization and Efficacy Evaluation of Synthetic Biocompatible Polymers Linking Natural Antioxidants
Molecules 2012, 17(11), 12734-12745; doi:10.3390/molecules171112734
Received: 13 July 2012 / Revised: 18 September 2012 / Accepted: 22 October 2012 / Published: 26 October 2012
Cited by 4 | PDF Full-text (738 KB) | HTML Full-text | XML Full-text
Abstract
The purpose of this work was the synthesis, characterization and efficacy evaluation of new biocompatible antioxidant polymers linking trans-ferulic acid or a-lipoic acid. In particular, ferulic or lipoic acid were introduced in the preformed polymeric backbone. The new antioxidant biopolymers [...] Read more.
The purpose of this work was the synthesis, characterization and efficacy evaluation of new biocompatible antioxidant polymers linking trans-ferulic acid or a-lipoic acid. In particular, ferulic or lipoic acid were introduced in the preformed polymeric backbone. The new antioxidant biopolymers were characterized by Fourier transform infrared spectroscopy and gel permeation chromatography. The degree of functionalization (moles of antioxidant per gram of polymer) was determined by the Gaur-Gupta method for free amino group determination and by the Folin method for the phenolic groups. Their ability to inhibit lipid peroxidation were estimated in rat liver microsomal membranes induced in vitro by tert-BOOH (tert-butyl hydroperoxide), as a source of free radicals. The DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging effect was also evaluated. The obtained systems, with different solubility, showed strong antioxidant and antiradical activities, suggesting potential use as packaging materials for foods, cosmetics, pharmaceuticals and personal care products. Moreover, the cytotoxicity of the synthesized polymers was also evaluated on Caco-2 cell cultures in order to verify their biocompatibility when exposed to an absorptive epithelial cell line. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle TLC Screening for Antioxidant Activity of Extracts from Fifteen Bamboo Species and Identification of Antioxidant Flavone Glycosides from Leaves of Bambusa. textilis McClure
Molecules 2012, 17(10), 12297-12311; doi:10.3390/molecules171012297
Received: 10 September 2012 / Revised: 19 September 2012 / Accepted: 12 October 2012 / Published: 19 October 2012
Cited by 10 | PDF Full-text (317 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Interest in the antioxidant activity of bamboo leaves is growing. To discover new sources of natural antioxidants, a TLC bioautography method combined with a new image processing method was developed to evaluate the antioxidant activity of leaf extracts from 15 different species [...] Read more.
Interest in the antioxidant activity of bamboo leaves is growing. To discover new sources of natural antioxidants, a TLC bioautography method combined with a new image processing method was developed to evaluate the antioxidant activity of leaf extracts from 15 different species of bamboo. The results showed that the methanolic extract of Bambusa. textilis McClure possessed the highest antioxidant activity among the selected bamboo species. To rapidly identify the antioxidant compounds, the crude extract of B. textilis McClure was analysed by HPLC-UV, and HPLC-micro-fractionation of the extract was carried out. Based on TLC bioautography-guided fractionation, three antioxidant fractions were isolated from B. textilis McClure by preparative chromatography. These three antioxidant compounds were identified as isoorientin 4''-O β-D-xylopyranoside (1), isoorientin 2''-O-α-L-rhamnoside (2) and isoorientin (3) according to their UV, MS, and NMR data. The proposed TLC screening method could therefore be an easy way to evaluate the antioxidant activity of bamboo leaves, and the results achieved should prove very helpful for promoting their utilization, as B. textilis McClure can be considered a promising plant source of natural antioxidants. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle Inhibitory Effects of Resveratrol Analogs on Mushroom Tyrosinase Activity
Molecules 2012, 17(10), 11816-11825; doi:10.3390/molecules171011816
Received: 26 July 2012 / Revised: 28 September 2012 / Accepted: 30 September 2012 / Published: 9 October 2012
Cited by 16 | PDF Full-text (240 KB) | HTML Full-text | XML Full-text
Abstract
Skin pigmentation disorders typically involve an overproduction or uneven distribution of melanin, which results in skin spots. Resveratrol can inhibit tyrosinase, the active enzyme in the synthesis of melanin, but it does not inhibit the synthesis of melanin to an extent that [...] Read more.
Skin pigmentation disorders typically involve an overproduction or uneven distribution of melanin, which results in skin spots. Resveratrol can inhibit tyrosinase, the active enzyme in the synthesis of melanin, but it does not inhibit the synthesis of melanin to an extent that enables its use alone as a skin whitening agent in pharmaceutical formulations, so its use as a coadjuvant in treatment of hyperpigmentation is suggested. Six resveratrol analogs were tested for tyrosinase inhibitory activity in vitro. Among the analogs tested, compound D was the most powerful tyrosinase inhibitor (IC50 = 28.66 µg/mL), two times more active than resveratrol (IC50 = 57.05 µg/mL), followed by the analogs A, E, B, F and C, respectively. This demonstrated that the hydroxylation at C4' on the phenolic ring was the molecular modification with most importance for the observed activity. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Figures

Open AccessArticle Evaluation of the Antioxidant and Anti-glication Effects of the Hexane Extract from Piper auritum Leaves in Vitro and Beneficial Activity on Oxidative Stress and Advanced Glycation End-Product-Mediated Renal Injury in Streptozotocin-Treated Diabetic Rats
Molecules 2012, 17(10), 11897-11919; doi:10.3390/molecules171011897
Received: 15 September 2012 / Revised: 21 September 2012 / Accepted: 7 October 2012 / Published: 9 October 2012
Cited by 11 | PDF Full-text (377 KB) | HTML Full-text | XML Full-text
Abstract
The aim of this study was to investigate the antioxidant activity of hexane extracts from leaves of Piper auritum (HS). Eight complementary in vitro test methods were used, including inhibition of DPPH· radicals, nitric oxide, superoxide anion, ion-chelating, ABTS, oxygen radical absorbance [...] Read more.
The aim of this study was to investigate the antioxidant activity of hexane extracts from leaves of Piper auritum (HS). Eight complementary in vitro test methods were used, including inhibition of DPPH· radicals, nitric oxide, superoxide anion, ion-chelating, ABTS, oxygen radical absorbance capacity, β-carotene bleaching and peroxy radical scavenging. The results indicated that HS possesses high antioxidant activity. To add to these finding we tested the effect against oxidative stress in liver, pancreas and kidney in diabetic rats. Low levels of SOD, CAT, GPx and GSH in diabetic rats were reverted to near normal values after treatment with HS. These results suggest that P. auritum prevents oxidative stress, acting as a suppressor of liver cell damage. Given the link between glycation and oxidation, we proposed that HS might possess significant in vitro antiglycation activity. Our data confirmed the inhibitory effect of HS on bovine serum albumin, serum glycosylated protein, glycation of LDL, and glycation hemoglobin. The effect of HS on diabetic renal damage was investigated using streptozotocin-induced diabetic rats. The oral administration of HS at a dose of 200 and 400 mg/kg body weight/day for 28 days significantly reduced advanced glycation endproduct (AGE) formation, elevated renal glucose and thiobarbituric acid-reactive substance levels in the kidneys of diabetic rats. This implies that HS would alleviate the oxidative stress under diabetes through the inhibition of lipid peroxidation. These findings indicate that oxidative stress is increased in the diabetic rat kidney and that HS can prevent renal damage associated with diabetes by attenuating the oxidative stress. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle The Antioxidant and Anti-inflammatory Effects of Phenolic Compounds Isolated from the Root of Rhodiola sachalinensis A. BOR
Molecules 2012, 17(10), 11484-11494; doi:10.3390/molecules171011484
Received: 4 July 2012 / Revised: 28 August 2012 / Accepted: 21 September 2012 / Published: 27 September 2012
Cited by 15 | PDF Full-text (283 KB)
Abstract
Isolation of compounds from the root of Rhodiola sachalinensis (RRS) yielded tyrosol (1), salidroside (2), multiflorin B (3), kaempferol-3,4′-di-O-β-D-glucopyranoside (4), afzelin (5), kaempferol (6), rhodionin (7), [...] Read more.
Isolation of compounds from the root of Rhodiola sachalinensis (RRS) yielded tyrosol (1), salidroside (2), multiflorin B (3), kaempferol-3,4′-di-O-β-D-glucopyranoside (4), afzelin (5), kaempferol (6), rhodionin (7), and rhodiosin (8). Quantification of these compounds was performed by high-performance liquid chromatography (HPLC). To investigate the antioxidant and anti-inflammatory effects of the compounds, DPPH radical scavenging, NBT superoxide scavenging and nitric oxide production inhibitory activities were examined in LPS-stimulated Raw 264.7 cells. We suggest that the major active components of RRS are herbacetin glycosides, exhibiting antioxidant activity, and kaempferol, exhibiting anti-inflammatory activity. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessCommunication Effects of Cultivar and Process Variables on Dynamic-Mechanical and Sensorial Behavior of Value-Added Grape-Based Smoothies
Molecules 2012, 17(10), 11421-11434; doi:10.3390/molecules171011421
Received: 7 August 2012 / Revised: 19 September 2012 / Accepted: 20 September 2012 / Published: 26 September 2012
Cited by 2 | PDF Full-text (301 KB) | HTML Full-text | XML Full-text
Abstract
The effects of either cooking temperature (45, 80, and 100 °C) or inclusion of seed particles on the dynamic-mechanical and sensorial properties of value-added Crimson seedless, Black Pearl, or Baresana grape-based smoothies were studied. The inclusion of seed particles resulted in significant [...] Read more.
The effects of either cooking temperature (45, 80, and 100 °C) or inclusion of seed particles on the dynamic-mechanical and sensorial properties of value-added Crimson seedless, Black Pearl, or Baresana grape-based smoothies were studied. The inclusion of seed particles resulted in significant increases of the phenolic content, both in Black Pearl and Baresana, but it did not affect in a negative way the sensorial characteristics of smoothies whereas it caused an increase of the viscoelastic behavior of Black Pearl and a slight decrease in Baresana grape-based smoothies. In particular, the investigated rheological parameters were the loss and storage modulus. Moreover, the loss tangent value (the ratio between loss and storage modulus) remained unchanged, indicating a pseudoplastic behavior of all samples, independent on the process conditions. The smoothies produced from Crimson grapes at the intermediate temperature (80 °C) showed sensorial and rheological characteristics similar to those manufactured at 45 °C and better than those manufactured at 100 °C. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle The Dual Action of Epigallocatechin Gallate (EGCG), the Main Constituent of Green Tea, against the Deleterious Effects of Visible Light and Singlet Oxygen-Generating Conditions as Seen in Yeast Cells
Molecules 2012, 17(9), 10355-10369; doi:10.3390/molecules170910355
Received: 12 June 2012 / Revised: 9 August 2012 / Accepted: 13 August 2012 / Published: 29 August 2012
Cited by 4 | PDF Full-text (2307 KB)
Abstract
Green tea extracts (GTEs) as well as their main component, the polyphenol epigallocatechin gallate (EGCG), are known for their versatile antioxidant, antimicrobial, antitumoral or anti-inflammatory effects. In spite of the huge beneficial action, there is increasing evidence that under certain conditions green [...] Read more.
Green tea extracts (GTEs) as well as their main component, the polyphenol epigallocatechin gallate (EGCG), are known for their versatile antioxidant, antimicrobial, antitumoral or anti-inflammatory effects. In spite of the huge beneficial action, there is increasing evidence that under certain conditions green tea and its components can be detrimental to living organisms. Using Saccharomyces cerevisiae strains with various defects in the response to oxidative stress, we found that GTEs or EGCG act in synergy with visible light, exhibiting either deleterious or protective effects depending on the solvent employed. Similar synergistic effects could be observed under singlet oxygen-generating conditions, such as light exposure in the presence of photosensitizers or UV-A irradiation, therefore solvent variance may represent a powerful tool to modulate the preparation of green tea extracts, depending on the intended target. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessArticle 6-Shogaol-Rich Extract from Ginger Up-Regulates the Antioxidant Defense Systems in Cells and Mice
Molecules 2012, 17(7), 8037-8055; doi:10.3390/molecules17078037
Received: 21 May 2012 / Revised: 23 June 2012 / Accepted: 2 July 2012 / Published: 4 July 2012
Cited by 29 | PDF Full-text (766 KB)
Abstract
The rhizome of ginger (Zingiber officinale Roscoe) is known to have several bioactive compounds including gingerols and shogaols which possess beneficial health properties such as anti-inflammatory and chemopreventive effects. Based on recent observations that 6-shogaol may have more potent bioactivity than [...] Read more.
The rhizome of ginger (Zingiber officinale Roscoe) is known to have several bioactive compounds including gingerols and shogaols which possess beneficial health properties such as anti-inflammatory and chemopreventive effects. Based on recent observations that 6-shogaol may have more potent bioactivity than 6-gingerol, we obtained a 6-shogaol-rich extract from ginger and examined its effects on the nuclear factor E2-related factor2 (Nrf2)/antioxidant response element (ARE) pathway in vitro and in vivo. 6-Shogaol-rich extract was produced by extracting ginger powder with 95% ethanol at 80 °C after drying at 80 °C (GEE8080). GEE8080 contained over 6-fold more 6-shogaol compared to the room temperature extract (GEE80RT). In HepG2 cells, GEE8080 displayed much stronger inductions of ARE-reporter gene activity and Nrf2 expression than GEE80RT. GEE8080 stimulated phosphorylations of mitogen-activated protein kinases (MAPKs) such as ERK, JNK, and p38. Moreover, the GEE8080-induced expressions of Nrf2 and HO-1 were attenuated by treatments of SB202190 (a p38 specific inhibitor) and LY294002 (an Akt specific inhibitor). In a mouse model, the GEE8080 decreased the diethylnitrosamine (DEN)-mediated elevations of serum aspartate transaminase and alanine transaminase as well as the DEN-induced hepatic lipid peroxidation. Inductions of Nrf2 and HO-1 by GEE8080 were also confirmed in the mice. In addition, the administration of GEE8080 to the mice also restored the DEN-reduced activity and protein expression of hepatic antioxidant enzymes such as superoxide dismutase, glutathione peroxidase and catalase. In conclusion, GEE8080, a 6-shogaol-rich ginger extract, may enhance antioxidant defense mechanism through the induction of Nrf2 and HO-1 regulated by p38 MAPK and PI3k/Akt pathway in vitro and in vivo. Full article
(This article belongs to the Special Issue Antioxidants 2012)

Review

Jump to: Research

Open AccessReview Antioxidant Action and Therapeutic Efficacy of Allium sativum L.
Molecules 2013, 18(1), 690-700; doi:10.3390/molecules18010690
Received: 23 November 2012 / Revised: 14 December 2012 / Accepted: 28 December 2012 / Published: 4 January 2013
Cited by 33 | PDF Full-text (164 KB)
Abstract
Allium sativum (L.) is rich in antioxidants which help destroy free radicals particles that can damage cell membranes and DNA, and may contribute to the aging process as well as the development of a number of conditions, including heart disease and cancer. [...] Read more.
Allium sativum (L.) is rich in antioxidants which help destroy free radicals particles that can damage cell membranes and DNA, and may contribute to the aging process as well as the development of a number of conditions, including heart disease and cancer. Antioxidants neutralize free radicals and may reduce or even help prevent some of the damage they cause over time. The antioxidant activity of fresh Allium sativum L. (garlic) is well known and is mainly due to unstable and irritating organosulphur compounds. Fresh garlic extracted over a prolonged period (up to 20 months) produces odourless aged garlic extract (AGE) containing stable and water soluble organosulphur compounds that prevent oxidative damage by scavenging free radicals. The aim of this review was to understand the mechanism of antioxidant action and therapeutic efficacy of garlic. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessReview Polyphenolic Profile and Biological Activity of Chinese Hawthorn (Crataegus pinnatifida BUNGE) Fruits
Molecules 2012, 17(12), 14490-14509; doi:10.3390/molecules171214490
Received: 27 September 2012 / Revised: 26 November 2012 / Accepted: 29 November 2012 / Published: 6 December 2012
Cited by 28 | 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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Antioxidants 2012)
Open AccessReview Recent Updates in Redox Regulation and Free Radical Scavenging Effects by Herbal Products in Experimental Models of Parkinson’s Disease
Molecules 2012, 17(10), 11391-11420; doi:10.3390/molecules171011391
Received: 30 August 2012 / Revised: 12 September 2012 / Accepted: 21 September 2012 / Published: 26 September 2012
Cited by 11 | PDF Full-text (353 KB) | HTML Full-text | XML Full-text
Abstract
Parkinson’s disease (PD) is a complex multifactorial disease marked by extensive neuropathology in the brain with selective yet prominent and progressive loss of mid-brain dopaminergic neurons. The etiological factors involved in the development of PD are still elusive, but oxidative stress arising [...] Read more.
Parkinson’s disease (PD) is a complex multifactorial disease marked by extensive neuropathology in the brain with selective yet prominent and progressive loss of mid-brain dopaminergic neurons. The etiological factors involved in the development of PD are still elusive, but oxidative stress arising when reactive oxygen species (ROS) exceed amounts required for normal redox signaling is considered one of the major factors. ROS cause oxidative damage to proteins, lipids, and DNA and are one of the most prominent factors related to neurodegeneration. Pre-clinical and clinical studies clearly demonstrate the effectiveness of oxidative stress in the pathogenesis of PD. Therefore, regulation of redox signaling and inhibiting excess ROS would contribute greatly not only to extend longevity but also to ameliorate the progression of dopaminergic cell death seen in patients with PD. Several herbal products are beneficial for maintaining nerve cell function and for treating various neurodegenerative disorders by reducing oxidative stress. Here, we summarize the recent knowledge concerning promising herbs that have shown significant beneficial effects based on regulation of redox status and ROS inhibition in toxin-induced PD models. Full article
(This article belongs to the Special Issue Antioxidants 2012)

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