Effect of antioxidant flavanone, naringenin, from Citrus junoson neuroprotection

Amyloid beta protein (Abeta)-induced free radical-mediated neurotoxicity is known as a leading hypothesis for a cause of Alzheimer's disease. Abeta increased free radical production and lipid peroxidation in PC12 nerve cells, resulting in apoptosis and cell death. The protective effect of naringenin, a major flavanone constituent isolated from Citrus junos, against Abeta-induced neurotoxicity was investigated using PC12 cells. Pretreatment with isolated naringenin and vitamin C prevented the generation of the Abeta-induced reactive oxygen species. Naringenin resulted in the decrease of Abeta toxicity in a manner of concentration dependence, which was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. However, treatment with these antioxidants inhibited the Abeta-induced neurotoxic effect. The antiamnestic activity of naringenin in vivo was also evaluated using ICR mice with amnesia induced by scopolamine (1 mg/kg body weight). Naringenin, when administered to ICR mice at 4.5 mg/kg body weight, significantly ameliorated scopolamine-induced amnesia as measured in the passive avoidance test. Therefore, these results indicate that micromolecular Abeta-induced in vitro oxidative cell stress is reduced by naringenin and naringenin may be a useful chemopreventive agent against a neurodegenerative disease such as Alzheimer's disease.     

Potent Inhibitory effect of flavonoids in Scutellaria baicalensis on amyloid beta protein-induced neurotoxicity

The free radical scavenging activities of two major flavonoids (baicalein and baicalin) in Scutellaria baicalensis were determined. The antioxidant capacities of baicalein and baicalin were determined by the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(*)(-) scavenging assay and showed about 110 and 70% vitamin C equivalent antioxidant capacity, respectively. Because amyloid beta (Abeta) protein is known to increase free radical production and lipid peroxidation in PC12 nerve cells, leading to apoptosis and cell death, treatment with baicalein and baicalin may result in the prevention of cellular damage by the Abeta-induced reactive oxygen species. We found that baicalein and baicalin resulted in a dose-dependent anti-Abeta toxicity by means of three different assays [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction, lactate dehydrogenase release, and trypan blue exclusion assays]. These results suggest that baicalein as well as baicalin can reduce the cytotoxicity of Abeta protein in PC12 cells, possibly by a reduction of oxidative stress, and these flavonoids may be useful in the chemoprevention of Alzheimer's disease.     

Antiproliferative effects of carotenoids extracted from Chlorella ellipsoidea and Chlorella vulgaris on human colon cancer cells

The antiproliferative activity of carotenoids separated from marine Chlorella ellipsoidea and freshwater Chlorella vulgaris has been evaluated. HPLC analysis revealed that the main carotenoid from C. ellipsoidea was composed of violaxanthin with two minor xanthophylls, antheraxanthin and zeaxanthin, whereas the carotenoid from C. vulgaris was almost completely composed of lutein. In an MTT assay, both semipurified extracts of C. ellipsoidea and C. vulgaris inhibited HCT116 cell growth in a dose-dependent manner, yielding IC(50) values of 40.73 +/- 3.71 and 40.31 +/- 4.43 microg/mL, respectively. In addition, treatment with both chlorella extracts enhanced the fluorescence intensity of the early apoptotic cell population in HCT116 cells. C. ellipsoidea extract produced an apoptosis-inducing effect almost 2.5 times stronger than that of the C. vulgaris extract. These results indicate that bioactive xanthophylls of C. ellipsoidea might be useful functional ingredients in the prevention of human cancers.     

Antioxidant and choleretic properties of Raphanus sativus L. sprout (Kaiware Daikon) extract

Brassica vegetables and glucosinolates contained therein are supposed to reduce the risk of cancer and to possess health-promoting properties. The benefits of a Brassica-based diet may be particularly expressed by eating sprouts, in which the glucosinolate content is higher than in mature vegetables. With this in mind, a first objective of this study was to evaluate the antioxidant properties of radish (Raphanus sativus L.) sprouts (Kaiware Daikon) extract (KDE), in which the glucosinolate glucoraphasatin (GRH), showing some antioxidant activity, is present at 10.5% w/w. The contribution of GRH to KDE's antioxidant activity was considered in two chemical assays (Trolox equivalent antioxidant capacity and Briggs-Rauscher methods). The total phenol assay by Folin-Ciocalteu reagent was performed to quantify the reducing capacity of KDE. Finally, on the basis of the putative choleretic properties of antioxidant plant extracts, the effect on the bile flow of KDE administration was investigated in an animal experimental model. The findings showed that KDE has antioxidant properties and significantly induced bile flow in rats administered 1.5 g/kg of body weight for 4 consecutive days.     

Antioxidant activity of Sicilian pistachio (Pistacia vera L. var. Bronte) nut extract and its bioactive components

Pistacia vera L. is the only species of Pistacia genus producing edible nuts. This paper investigates the antioxidant potential of a Sicilian variety of pistachio nut by chemical as well as biological assays and measured antioxidant vitamins and a number of antioxidant polyphenols in either the hydrophilic and/or the lipophilic nut extract. In accordance with the majority of foods, the total antioxidant activity, measured as a TAA test, was much higher (50-fold) in the hydrophilic than in the lipophilic extract. Substantial amounts of total phenols were measured. The hydrophilic extract inhibited dose-dependently both the metal-dependent and -independent lipid oxidation of bovine liver microsomes, and the Cu+2-induced oxidation of human low-density lipoprotein (LDL). Peroxyl radical-scavenging as well as chelating activity of nut components may be suggested to explain the observed inhibition patterns. Among tocopherols, gamma-tocopherol was the only vitamin E isomer found in the lipophilic extract that did not contain any carotenoid. Vitamin C was found only in a modest amount. The hydrophilic extract was a source of polyphenol compounds among which trans-resveratrol, proanthocyanidins, and a remarkable amount of the isoflavones daidzein and genistein, 3.68 and 3.40 mg per 100 g of edible nut, respectively, were evaluated. With the exception of isoflavones that appeared unmodified, the amounts of other bioactive molecules were remarkably reduced in the pistachio nut after roasting, and the total antioxidant activity decreased by about 60%. Collectively, our findings provide evidence that the Sicilian pistachio nut may be considered for its bioactive components and can effectively contribute to a healthy status.     

Antioxidant properties of crocin from Gardenia jasminoides Ellis and study of the reactions of crocin with linoleic acid and crocin with oxygen

Crocin-a water soluble carotenoid-is found in the fruits of gardenia (Gardenia jasminoides Ellis) and in the stigmas of saffron (Crocus sativus Linne). For crocin purification, gardenia fruits are extracted with 50% acetone, followed by ether washing, ion exchange, and separation by preparative HPLC. Purified crocin with purity of >99.6% has an antioxidative activity at concentrations up to 40 ppm. At 20 ppm the antioxidative activity of crocin is comparable to that of BHA. The antioxidant property of crocin as evaluated by the thiocyanate method was better than with the thiobarbituric acid method. The adduct between the linoleic acid radical and crocin was detected by LC-MS. When crocin reacted with oxygen in the presence of FeSO(4), intermediates such as monohydroperoxides and dihydroperoxides of crocin were formed and detected by LC-MS.     

Phlorotannins from brown algae (Fucus vesiculosus) inhibited the formation of advanced glycation endproducts by scavenging reactive carbonyls

Accumulation of advanced glycation end products (AGEs) in vivo is associated with aging, diabetes, Alzheimer's disease, renal failure, etc. The objective of this study was to investigate the inhibitory effects of brown algae Fucus vesiculosus phlorotannins on the formation of AGEs. F. vesiculosus phlorotannins were extracted using 70% acetone. The resultant extract was fractionated into dichloromethane, ethyl acetate, butanol, and water fractions. The ethyl acetate fraction was further fractionated into four subfractions (Ethyl-F1 to -F4) using a Sephadex LH-20 column. F. vesiculosus acetone extract or fractions significantly inhibited the formation of AGEs mediated by glucose and methylglyoxal in a concentration-dependent manner. The concentrations of F. vesiculosus extracts required to inhibit 50% of albumin glycation (EC(50)) in the bovine serum albumin (BSA)-methylglyoxal assay were lower than those of aminoguanidine (a drug candidate for diabetic complication), except for F. vesiculosus acetone extract and dichloromethane fraction. In the BSA-glucose assay, F. vesiculosus extracts inhibited BSA glycation more than or as effectively as aminoguanidine, except for Ethyl-F3 and -F4. The ethyl acetate fraction and its four subfractions scavenged more than 50% of methylglyoxal in two hours. The hypothesis whether F. vesiculosus phlorotannins scavenged reactive carbonyls by forming adducts was tested. Phloroglucinol, the constituent unit of phlorotannins, reacted with glyoxal and methylglyoxal. Five phloroglucinol-carbonyl adducts were detected and tentatively identified using HPLC-ESI-MS(n).     

Determination of antioxidant potential of volatile extracts isolated from various herbs and spices

Antioxidant activities of volatile extracts isolated from thyme, basil, rosemary, chamomile, lavender, and cinnamon were evaluated by two independent assays: the aldehyde/carboxylic acid assay and the conjugated diene assay. The volatile extracts were prepared from dried herbs and spices using liquid-liquid continuous extraction following steam distillation under reduced pressure (55 degrees C and 95 mmHg). The antioxidant activities of the extracts decreased in the following order in both of the lipophilic assay systems: thyme > basil > rosemary > chamomile > lavender and cinnamon. Thyme and basil extracts inhibited the oxidation of hexanal for 40 days at the levels of 10 microg/mL and 50 microg/mL, respectively. The extracts of thyme and basil were effective in retarding methyl linoleate deterioration at 40 degrees C, with activity increasing with concentration in the range 10-200 microg/mL. At a concentration of 50 microg/mL, thyme extract was similar in antioxidant activity to BHT and alpha-tocopherol in the conjugated diene assay. The antioxidant potentials of the volatile extracts used in this study were accurately measured by the lipophilic systems, such as the aldehyde/carboxylic acid assay and the conjugated diene assay.     

Effect of black soybean extract on the suppression of the proliferation of human AGS gastric cancer cells via the induction of apoptosis

Black soybean is known to have a health-promoting effect because of its high content of polyphenolic compounds and antioxidant activities. The objective of the present study was to investigate the chemopreventive effects of black soybean extract against human AGS gastric cancer cells and its possible mechanism in inducing apoptosis. Black soybean extract was obtained by extracting black soybean with acidified aqueous acetone, and its phytochemical constituents, as determined by HPLC-DAD methods, were demonstrated to contain various phenolics. The black soybean extract inhibited AGS cell growth in a dose-dependent manner with an IC(50) of 3.69 mg/mL as measured by the MTT assay. This growth inhibition effect was further confirmed by the CFDA-SE assay. Flow cytometry analysis showed that black soybean extract dose-dependently induced apoptosis of AGS cells. Moreover, the involvement of black soybean extract in inducing apoptosis was confirmed by the expression of Bax, Bcl-2, caspase-3, and PARP. The results of the present study indicated that black soybean extract could be used as an apoptosis inducer in AGS cells and a natural chemopreventive agent in the treatment of human gastric cancer.     

Chemical composition of the volatile extract and antioxidant activities of the volatile and nonvolatile extracts of Egyptian corn silk (Zea mays L.)

A total of 36 compounds, which comprised 99.4% of the extract, were identified by gas chromatography and mass spectrometry (GC-MS) in the volatile dichloromethane extract obtained from Egyptian corn silk. The main constituents of the volatile extract were cis-alpha-terpineol (24.22%), 6,11-oxidoacor-4-ene (18.06%), citronellol (16.18%), trans-pinocamphone (5.86%), eugenol (4.37%), neo-iso-3-thujanol (2.59%), and cis-sabinene hydrate (2.28%). Dried Egyptian corn silk was also directly extracted with petroleum ether, ethanol, and water. All extracts from solvent extraction and the volatile extract described above exhibited clear antioxidant activities at levels of 50-400 microg/mL in the 2,2-diphenyl-1-picrylhydrazyl (DPPH)/linoleic acid assay. The ethanol extract inhibited DPPH activity by 84% at a level of 400 microg/mL. All samples tested via the beta-carotene bleaching assay also exhibited satisfactory antioxidant activity with clear dose responses. This study indicates that corn silk could be used to produce novel natural antioxidants as well as a flavoring agent in various food products.     

Antioxidant and antimutagenic properties of aqueous extract of date fruit (Phoenix dactylifera L. Arecaceae).

Fruits of the date palm (Phoenix dactylifera L. Arecaceae) are very commonly consumed in many parts of the world and are a vital component of the diet in most of the Arabian countries. This preliminary study documents for the first time its antioxidant and antimutagenic properties in vitro. There was a dose-dependent inhibition of superoxide and hydroxyl radicals by an aqueous extract of date fruit. The amount of fresh extract required to scavenge 50% of superoxide radicals was equivalent to 0.8 mg/mL of date fruit in the riboflavin photoreduction method. An extract of 2.2 mg/mL of date fruit was needed for 50% hydroxyl-radical-scavenging activity in the deoxyribose degradation method. Concentrations of 1.5 and 4.0 mg/mL completely inhibited superoxide and hydroxyl radicals, respectively. Aqueous date extract was also found to inhibit significantly the lipid peroxidation and protein oxidation in a dose-dependent manner. In an Fe(2+)/ascorbate system, an extract of 1.9 mg/mL of date fruit was needed for 50% inhibition of lipid peroxides. In a time course inhibition study of lipid peroxide, at a 2.0 mg/mL concentration of date extract, there was a complete inhibition of TBARS formation in the early stages of the incubation period that increased during later stages of the incubation. Similarly, in the high Fe(2+)/ascorbate induction system a concentration of 2.3 mg/mL inhibited carbonyl formation measured by DNPH reaction by 50%. Moreover, a concentration of 4.0 mg/mL completely inhibited lipid peroxide and protein carbonyl formation. Date fruit extract also produced a dose-dependent inhibition of benzo(a)pyrene-induced mutagenecity on Salmonella tester strains TA-98 and TA-100 with metabolic activation. Extract from 3.6 mg/plate and 4.3 mg/plate was found required for 50% inhibition of His+ revertant formation in TA-98 and TA-100, respectively. These results indicate that antioxidant and antimutagenic activity in date fruit is quite potent and implicates the presence of compounds with potent free-radical-scavenging activity.     

Crocetin, dimethylcrocetin, and safranal bind human serum albumin: stability and antioxidative properties

Crocetin (CRT) and dimethylcrocetin (DMCRT) are derived from crocins which are found in the stigmas of saffron (Crocus sativus L.), while safranal is the main component of saffron's essential oil. The aim of the present study was to examine their interaction with human serum albumin in aqueous solution at physiological conditions using constant protein concentration and various ligand contents. FT-IR and UV-visible spectroscopic methods were used to determine the ligands' binding mode, the binding constant, and the effects of ligand complexation on protein secondary structure. Structural analysis showed that crocetin, dimethylcrocetin, and safranal bind nonspecifically (H-bonding) via protein polar groups with binding constants of Kcrt =2.05 (+/-0.30) x 103 M-1, Kdmcrt = 9.60 (+/-0.35) x 104 M-1, and Ksaf = 2.11 (+/-0.35) x 103 M-1. The protein secondary structure showed no major alterations at low ligand concentrations (1 microM), whereas at higher content (1 mM), decrease of alpha-helix from 55% (free HSA) to 43-45% and increase of beta-sheet from 17% (free HSA) to 18-22% and random coil 7% (free HSA) to 10-14% occurred in the ligand-HSA complexes. The results point to a partial unfolding of protein secondary structure at high ligand content. The antioxidant activity of CRT, DMCRT, and safranal was also tested by the DPPH* antioxidant activity assay, and their IC50 values were compared to that of well-known antioxidants such as Trolox and butylated hydroxy toluene (BHT). The IC50 values of CRT and safranal were 17.8 +/- 1 microg/mL and 95 +/- 1 microg/mL, respectively, while the inhibition of DMCRT reached a point of 38.8%, which corresponds to a concentration of 40 microg/mL, and then started to decrease. The IC50 values of Trolox and BHT were 5.2 +/- 1 microg/mL and 5.3 +/- 1 microg/mL, respectively.     

Carotenoid changes of intact watermelons after storage

Watermelon contains lycopene, a red carotenoid pigment that has strong antioxidant properties. The lycopene content of watermelon is substantial, contributing 8-20 mg per 180 g serving. There are no reports on carotenoid changes in whole watermelon during storage. Three types of watermelon, open-pollinated seeded, hybrid seeded, and seedless types, were stored at 5, 13, and 21 degrees C for 14 days and flesh color, composition, and carotenoid content were compared to those of fruit not stored. Watermelons stored at 21 degrees C had increased pH, chroma, and carotenoid content compared to fresh fruit. Compared to fresh fruit, watermelons stored at 21 degrees C gained 11-40% in lycopene and 50-139% in beta-carotene, whereas fruit held at 13 degrees C changed little in carotenoid content. These results indicate that carotenoid biosynthesis in watermelons can be affected by temperature and storage.     

Saffron as a source of novel acetylcholinesterase inhibitors: molecular docking and in vitro enzymatic studies

Inhibitors of acetylcholine breakdown by acetylcholinesterase (AChE) constitute the main therapeutic modality for Alzheimer's disease. In the search for natural products with inhibitory action on AChE, this study investigated the activity of saffron extract and its constituents by in vitro enzymatic and molecular docking studies. Saffron has been used in traditional medicine against Alzheimer's disease. Saffron extract showed moderate AChE inhibitory activity (up to 30%), but IC(50) values of crocetin, dimethylcrocetin, and safranal were 96.33, 107.1, and 21.09 μM, respectively. Kinetic analysis showed mixed-type inhibition, which was verified by in silico docking studies. Safranal interacts only with the binding site of the AChE, but crocetin and dimethylcrocetin bind simultaneously to the catalytic and peripheral anionic sites. These results reinforce previous findings about the beneficial action of saffron against Alzheimer's disease and may be of value for the development of novel therapeutic agents based on carotenoid-based dual binding inhibitors.     

Antioxidant activities of astaxanthin and related carotenoids

The antioxidant activities of astaxanthin and related carotenoids have been measured by employing a newly developed fluorometric assay. This assay is based on 4,4-difluoro-3,5-bis(4-phenyl-1, 3-butadienyl)-4-bora-3a,4a-diaza-s-indacene (BODIPY 665/676) as an indicator; 2,2'-azobis-2,4-dimethylvaleronitrile (AMVN) as a peroxyl radical generator; and 6-hydroxy-2,5,7, 8-tetramethylchroman-2-carboxylic acid (Trolox) as a calibrator in an organic and liposomal media. By employing this assay, three categories of carotenoids were examined: namely, the hydrocarbon carotenoids lycopene, alpha-carotene, and beta-carotene; the hydroxy carotenoid lutein; and the alpha-hydroxy-ketocarotenoid astaxanthin. The relative peroxyl radical scavenging activities of Trolox, astaxanthin, alpha-tocopherol, lycopene, beta-carotene, lutein, and alpha-carotene in octane/butyronitrile (9:1, v/v) were determined to be 1.0, 1.0, 1.3, 0.5, 0.4, 0.3, and 0.2, respectively. In dioleoylphosphatidyl choline (DOPC) liposomal suspension in Tri-HCl buffer (pH 7.4 at 40 degrees C), the relative reactivities of astaxanthin, beta-carotene, alpha-tocopherol, and lutein were found to be 1.00, 0.9, 0.6, and 0.6, respectively. When BODIPY 665/676 was replaced by 4,4-difluoro-5-(4-phenyl-1,3-butadienyl)-4-bora-3a, 4a-diaza-s-indacene-3-undecanoic acid (BODIPY 581/591 C(11)) as an indicator, astaxanthin showed the highest antioxidant activity toward peroxyl radicals. The relative reactivities of Trolox, astaxanthin, alpha-tocopherol, alpha-carotene, lutein, beta-carotene, and lycopene were determined to be 1.0, 1.3, 0.9, 0.5, 0.4, 0.2, and 0.4, respectively.     

Novel low-density lipoprotein (LDL) oxidation model: antioxidant capacity for the inhibition of LDL oxidation

A novel model of peroxyl radical initiated low-density lipoprotein (LDL) oxidation (LDL oxidation model for antioxidant capacity, or LOMAC) was developed to assess the free radical scavenging capacity of antioxidants and the extracts of natural products. A water-soluble free radical initiator, 2,2'-azobis(amidinopropane) dihydrochloride, was used at physiological temperature (37 degrees C) to generate peroxyl radicals to catalyze lipid oxidation of LDL isolated from human plasma samples. Headspace hexanal, a major decomposition product of LDL oxidation, was measured by a headspace gas chromatograph as an indicator of antioxidant capacity of different concentrations of pure antioxidants (vitamins C and E) and the extracts of natural products (fresh apple phytochemical extracts). All vitamin C and E and apple extract concentrations tested resulted in increasing partial suppression and delay of LDL oxidation. On the basis of the median effective dose (EC(50)) calculated for each compound or extract tested, the LOMAC value of 100 g of apple against LDL oxidation was equivalent to 1470 mg of vitamin E or to 402 mg of vitamin C. This study shows that the LOMAC assay can be routinely used to analyze or screen antioxidants or phytochemical extracts against LDL oxidation to prevent cardiovascular disease. The food-specific LOMAC values will be very useful as a new alternative biomarker for future epidemiological studies of cardiovascular disease.     

Antiinflammatory properties of the muscadine grape (Vitis rotundifolia)

The muscadine grape possesses one of the highest antioxidant levels among fruits; yet, the effect of this fruit on mammalian metabolic systems has not received significant attention. To examine the antiinflammatory properties of the muscadine, grape skins were dried, pulverized, and extracted (10% w/v) with 50% ethanol. The extract was then tested in two different assays: the release of superoxide in phorbol myristate acetate-activated neutrophils and the release of cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-beta), and interleukin-6 (IL-6)] by lipopolysaccharide-activated peripheral blood mononuclear cells. The release of superoxide and cytokines was inhibited by increasing concentrations of the extract. A 1:100 dilution of the extract inhibited superoxide release by approximately 60% while the release of TNF-alpha and IL-1beta was reduced at a dilution of 1:200 by approximately 15 and 90%, respectively (all P < 0.05). The inhibition pattern on the release of IL-6 was similar to that seen with TNF-alpha. In a related in vivo study, rats were fed a diet containing 5% (wt/wt) dried muscadine grape skins for 14 days and then were injected with carrageenan in the foot pad. After 3 h, paw edema was measured and the rats on the grape skin diet had approximately 50% less paw edema than controls (P < 0.05). These results demonstrate that the muscadine grape skin powder possesses significant in vitro and in vivo antiinflammatory properties.     

Trolox equivalent antioxidant capacity of different geometrical isomers of alpha-carotene, beta-carotene, lycopene, and zeaxanthin.

Isomerization of carotenoids, which is often encountered in food processing under the influence of temperature and light, may play a role in the observed protective effects of this group of secondary plant products. Investigation of in vitro antioxidant activity of prominent carotenoid geometrical isomers was undertaken in light of recent reports illustrating a large percentage of carotenoid (Z)-isomers in biological fluids and tissues. Alpha-carotene, beta-carotene, lycopene, and zeaxanthin were isolated from foods or supplements and subsequently photoisomerized with iodine as a catalyst. Major Z-isomers of each carotenoid were fractionated by semipreparative C(30) HPLC. In vitro antioxidant activity of all isomers collected was measured photometrically using the Trolox equivalent antioxidant capacity (TEAC) assay. TEAC values of 17 geometrical isomers investigated ranged from 0.5 to 3.1 mmol/L. Three unidentified (Z)-isomers of lycopene showed the highest antioxidant activity, being significantly higher than the result for (all-E)-lycopene, which had approximately two times the activity of (all-E)-beta-carotene. On the other hand, (9Z)-zeaxanthin had a more than 80% lower TEAC value compared to that of (all-E)-lycopene. These results allow for the in vivo relevance of (Z)-isomers of carotenoids to be considered.     

Antioxidant property of an ethanol extract of the stem of Opuntia ficus-indica var. saboten

An ethanol extract of the stem of Opuntia ficus-indica var. saboten (OFS) was assessed to determine the mechanism(s) of its antioxidant activity. The ethanol extract exhibited a concentration-dependent inhibition of linoleic acid oxidation in a thiocyanate assay system. In addition, the OFS extract showed dose-dependent free-radical scavenging activity, including DPPH radicals, superoxide anions (O(2)(*-)), and hydroxyl radicals (*OH), using different assay systems. The OFS ethanol extract was also found to be effective in protecting plasmid DNA against the strand breakage induced by hydroxyl radicals in a Fenton's reaction mixture. Furthermore, the extract showed significant (p < 0.01) dose-dependent protection of mouse splenocytes against glucose oxidase-mediated cytotoxicity. Finally, the OFS extract was characterized as containing a high amount of phenolics (180.3 mg/g), which might be the active compounds responsible for the antioxidant properties of the OFS extract.