Antioxidants are the essential defense mechanism to protect the body against free radical damage. The objective of the study was to investigate the in vitro antioxidant activity of different parts of Withania somnifera (leaves, fresh tubers and dry tubers) towards free radical DPPH and the extent of inhibition of lipid peroxidation using hydrogen peroxide as prooxidant. The plant extracts exhibited significant antioxidant effect in the order as follows: leaves>fresh tubers>dry tubers. The results suggested that Withania somnifera could be a potential source of antioxidants and may be used in preparations to combat free radical mediated damage.
Free radicals; Antioxidants; Lipid Peroxidation and Medicinal Plants
Cyanthillium cinereum (Less.) H. Rob. (Asteraceae) has been traditionally known for its medicinal properties, all aspects of which are yet to be exploited. This study was aimed at investigating the therapeutic potential of polar (methanolic and aqueous) and nonpolar (hexane and chloroform) crude extracts of the whole plant. Several parameters including free-radical (DPPH•, ABTS•+, H2O2 and •OH) scavenging, reducing power, protection of DNA against oxidative damage, cytotoxicity, inhibition of oxidative hemolysis in erythrocytes, total phenolic content and inhibition of lipid peroxidation were examined. All the free-radical generating assay models demonstrated positive scavenging efficiency with differential but considerable magnitudes for the four extracts. However, only the hexane extract showed significant H2O2 scavenging effect. Lipid peroxidation was estimated by thiobarbituric acid-malondialdehyde (MDA) reaction, and a high degree of inhibition was shown by all the extracts. Reducing power of the polar extracts was higher than the non-polar ones. All extracts showed a concentration-dependent increase in phenolic contents. Oxidative damage to erythrocytes was hindered by all extracts in diverse degrees. XTT assay showed that all extracts have mild cytotoxic property. The aqueous extract evidently demonstrated protective effect on pBR322 plasmid DNA against oxidative breakdown. These results suggested the potential of C. cinereum as medicine against free-radical-associated oxidative damage and related degenerative diseases involving metabolic stress, genotoxicity and cytotoxicity.
Cellular damage induced by free-radicals like Reactive Oxygen and Nitrogen Species (ROS and RNS) has been implicated in several disorders and diseases, including ageing. Hence naturally occurring anti-oxidant rich-herbs play a vital role in combating these conditions. The present study was carried out to investigate the in vitro free-radical quenching capacity of a known Ayurvedic poly-herbal formulation called Vayasthapana Rasayana.
Methanol extracts of Vayasthapana Rasayana formulation (VRF) were studied for in vitro total antioxidant activity along with phenolic content and reducing power. In vitro assays like DPPH, FRAP, ABTS scavenging to evaluate radical quenching potential were performed.
The formulation has shown 94% at 0.1 mg/ml DPPH free-radical scavenging activity as against 84% at 0.1 mg/ml for standard ascorbic acid (IC50 value 5.51 μg/ml for VRF and 39 μg/ml for standard). It has a significant higher ferric reducing potential also (OD 0.87 at 700 nm & 0.21 at 0.1 mg/ml for VRF and standard, respectively). The total phenolic content (gallic acid equivalent) of the VRF is 8.3 mg per g of dry mass. Total antioxidant capacity of the formulation, estimated by FRAP was 1150 ± 5 μM Fe(II)/g dry mass. ABTS radical scavenging activity of VRF was 69.55 ± 0.21% at 100 μg/ml concentration with a IC50 value of 69.87 μg/ml as against 9% and 95% by ascorbic acid and Trolox (at 70.452 μg/ml and 0.250 μg/ml concentrations, respectively).
In Indian traditional Ayurvedic system, use of VRF is in regular practice for mainly combating age-related disorders and diseases as many of the components of the Rasayana are known for their free-radical scavenging activity. This study has validated the potential use of VRF as an anti-oxidant to fight age-related problems.
This study was carried out to investigate the antioxidant and free radical scavenging activity of methanolic extract of Madhuca indica bark in varios systems. DPPH radical, superoxide anion radical, nitric oxide radical, hydroxyl radical, lipid peroxidation, and total phenolic content assays were carried out to evaluate the antioxidant potential of the extract. The percentage inhibition of 40 μg/ml concentration of MMI in DPPH radical scavenging model was found as 74.1%. The scavenging of nitric oxide by the plant extract was concentration dependent and IC50 value of rutin was found to be 161.7 μg/ml. MMI elicited significant and concentration-dependent superoxide radical scavenging effect with MMI as well as standard curcumin, which exhibited IC50 values of 38.1 and 5.84 μg/ml, respectively. MMI demonstrated significant scavenging activity of OH- radical generated from Fe2+-ascorbate-EDTA-H2O2 in a concentration-dependent manner. The extract showed a significant dose-dependent free radical scavenging activity in all the models. The extract showed the presence of high phenolic content corresponding to 98.48 μg equivalent of gallic acid and the antioxidant activity could be attributed to this.
Antioxidant activity; DPPH; Madhuca indica; nitric oxide radical
It is well known that the over production of reactive oxygen species is harmful for living organisms and it damages major cellular constituents such as DNA, protein, and lipid. At present, searching of new plant sources having free radical scavenging activity is an important field of research in phytomedicine as natural products are safe and relatively low cost. In this respect, attention has been focused to evaluate the antioxidant potential of hydro-methanolic extract of seed of Caesalpinia bonduc (Caesalpenacae) using different in vitro models. To evaluate the antioxidant activity, extract was examined on 2, 2-diphenyl-1-picrylhydrazyl radical scavenging effect, scavenging of hydrogen peroxide, hydroxyl radical scavenging potential, and anti-lipid peroxidation activity by biochemical methods. Total phenol and flavonoids contents in the said extract were measured biochemically as per standard methods. Results were compared with butylated hydroxyl toluene and α-tocopherol. Results indicated that hydro-methanolic extract has strong scavenging activity on 2, 2-diphenyl-1-picrylhydrazyl radical with IC50 value 157.4 μg/ml, hydroxyl radical with IC50 value 61.9 μg/ml and hydrogen peroxide with IC50 value 64.32 μg/ml. Hydro-methanolic extract also showed notable inhibition in lipid peroxidation having IC50 value 58.87 μg/ml. Phytochemical study focused that the extract is rich in phenolic compounds (24.66 mg gallic acid equivalent/g dried extract) and flavonoids (136.65 mg quercetin equivalent/g dried extract). Findings of the experiment indicated that the hydro-methanolic extract of seed of Caesalpinia bonduc is a source of natural antioxidants.
Antioxidant; Caesalpinia bonduc; free radicals; lipid peroxidation
Free radical production occurs continuously in all cells as part of normal cellular function. However, excess free radical production originating from endogenous or exogenous sources might play a role in many diseases. Antioxidants prevent free radical induced tissue damage by preventing the formation of radicals, scavenging them, or by promoting their decomposition. This article reviews the basic chemistry of free radical formation in the body, the consequences of free radical induced tissue damage, and the function of antioxidant defence systems, with particular reference to the development of atherosclerosis.
Key Words: free radicals • antioxidants • oxidative stress • coronary heart disease • atherosclerosis
In the present study, in vitro antioxidant, free radical scavenging capacity, and hepatoprotective activity of methanol extracts from Polyalthia longifolia and Cassia spectabilis were evaluated using established in vitro models such as ferric-reducing antioxidant power (FRAP), 2,2-diphenyl-1-picryl-hydrazyl (DPPH•), hydroxyl radical (OH•), nitric oxide radical (NO•) scavenging, metal chelating, and antilipidperoxidation activities. Interestingly, all the extracts showed considerable in vitro antioxidant and free radical scavenging activities in a dose-dependent manner when compared to the standard antioxidant which verified the presence of strong antioxidant compound in leaf extracts tested. Phenolic and flavonoid content of these extracts is significantly correlated with antioxidant capacity. Since P. longifolia extract was exhibited better in vitro antioxidant activities, it was subjected for in vivo hepatoprotective activity in paracetamol-intoxicated mice. Therapy of P. longifolia showed the liver protective effect on biochemical and histopathological alterations. Moreover, histological studies also supported the biochemical finding, that is, the maximum improvement in the histoarchitecture of the liver. Results revealed that P. longifolia leaf extract could protect the liver against paracetamol-induced oxidative damage by possibly increasing the antioxidant protection mechanism in mice. Our findings indicated that P. longifolia and C. spectabilis have potential as good sources of natural antioxidant/antiaging compounds.
This study evaluated the in vitro antioxidant potential of petroleum ether (60–80°C), chloroform, and methanol extract of the fruits of Dregea volubilis Benth (Asclepiadaceae). The different antioxidant assays, including total antioxidant activity, reducing power, free radical, super oxide anion radical, nitric oxide scavenging, lipid peroxidation, and total phenolic content were studied. The extracts exhibited potent total antioxidant activity that increased with increasing amount of extract concentration, which was compared with standard drug vitamin C at different concentrations as extracts. The different concentrations of all the extracts and vitamin C showed inhibition on lipid peroxidation. In addition, all the extracts had effective reducing power, free radical scavenging, super oxide anion scavenging, nitric oxide scavenging, lipid peroxidation, and total phenolic content depending on concentration. These various antioxidant activities were compared with standard antioxidant such as vitamin C at different concentration as different extracts.
Dregea volubilis; free-radical scavenging; in vitro antioxidant
The study was planned to evaluate modulatory effect of aqueous extract of Piper betle leaf (PBL) on ionizing radiation mediated oxidative stress leading to normal tissues damage during radiotherapy and other radiation exposures. The total polyphenols and flavonoids known as free radical scavenger (chelators) were measured in the extract. To ascertain antioxidant potential of PBL extract, we studied free radical scavenging, metal chelation, reducing power, lipid peroxidation inhibition and ferric reducing antioxidant properties (FRAP ) using in vitro assays. Mice were exposed to varied radiation doses administered with the same extract prior to irradiation to confirm its oxidative stress minimizing efficacy by evaluating ferric reducing ability of plasma, reduced glutathione, lipid peroxidation and micro-nuclei frequency. PBL extract was effective in scavenging DPPH (up to 92% at 100 µg/ml) and superoxide radicals (up to 95% at 80 µg/ml), chelated metal ions (up to 83% at 50 µg/ml) and inhibited lipid peroxidation (up to 45.65% at 500 µg/ml) in a dose dependant manner using in vitro model. Oral administration of PBL extract (225 mg/kg body weight) 1 hr before irradiation in mice significantly enhanced (p < 0.01) radiation abated antioxidant potential of plasma and GSH level in all the observed organs. The treatment with extract effectively lowered the radiation induced lipid peroxidation at 24 hrs in all the selected organs with maximum inhibition in thymus (p < 0.01). After 48 hrs, lipid peroxidation was maximally inhibited in the group treated with the extract. Frequency of radiation induced micronucleated cells declined significantly (34.78%, p < 0.01) at 24 hrs post-irradiation interval by PBL extract administration. The results suggest that PBL extract has high antioxidant potential and relatively non-toxic and thus could be assertively used to mitigate radiotherapy inflicted normal tissues damage and also injuries caused by moderate doses of radiation during unplanned exposures.
oxidative stress; Piper betle; ionizing radiation; lipid peroxidation; glutathione
Artemisia parviflora leaf extracts were evaluated for potential antimicrobial and antioxidant properties. Antimicrobial susceptibility assay was performed against ten standard reference bacterial strains. Antioxidant activity was analyzed using the ferric thiocyanate and 2, 2-Diphenyl-1-Picrylhydrazyl (DPPH) assays. Radical scavenging activity and total phenolic content were compared. Phytochemical analyses were performed to identify the major bioactive constitution of the plant extract.
Hexane, methanol and ethyl acetate extracts of A. parviflora leaves exhibited good activity against the microorganisms tested. The n-hexane extract of A. parviflora showed high inhibition of the growth of Pseudomonas aeruginosa, Escherichia coli and Shigella flexneri. Methanol extract showed strong radical scavenging and antioxidant activity, other extracts showed moderate antioxidant activity. The major derivatives present in the extracts are of terpenes, steroids, phenols, flavonoids, tannins and volatile oil.
The results obtained with n-hexane extract were particularly significant as it strongly inhibited the growth of P. aeruginosa, E. coli and S. flexneri. The major constituent of the n-hexane extract was identified as terpenes. Strong antioxidant activity could be observed with all the individual extracts. The antimicrobial and antioxidant property of the extracts were attributed to the secondary metabolites, terpenes and phenolic compounds present in A. parviflora and could be of considerable interest in the development of new drugs.
Artemisia; Terpenoids; Antimicrobial; Antioxidant; Radical scavenging activity
The free radical scavenging potential of the plant Alocasia indica(Linn.) was studied by using different antioxidant models of screening like scavenging of 1,1-diphenyl-2-picryl hydrazyl radical, nitric oxide radical, superoxide anion radical, hydroxyl radical, iron chelating activity, total antioxidant capacity, non-enzymatic glycosylation of haemoglobin, rapid screening for antioxidant compounds by thin layer chromatography. The hydroalcoholic extract at 1000 μg/ml showed maximum scavenging of superoxide radical (87.17) by riboflavin-NBT-system, followed by scavenging of stable radical 1,1-diphenyl-2-picryl hydrazyl radical (83.48%), nitric oxide radical (74.09%) hydroxyl radical (60.96%) at the same concentration. However the extract showed only moderate activity by iron chelation (68.26%). That could be due to higher phenolic content in the extract. This finding suggests that hydro alcoholic extract of A. indica possess potent in vitro antioxidant activity as compared to the standard ascorbic acid. The results justify the therapeutic applications of the plant in the indigenous system of medicine, augmenting its therapeutic value.
Antioxidant; free radicals; Alocasia indicia; lipid peroxidation; ascorbic acid
Herbal and natural products have been used in folk medicine for centuries throughout the world. There has been renewed interest in screening higher plants for novel biologically active compounds, particularly those that effectively intervene in human ailments in the field of chronic diseases. The present study has been taken up to evaluate the free radical scavenging activity and tumor cell suppression potential of Premna serratifolia leaf in various in vitro model systems. The methanolic extract of P. serratifolia leaf was obtained by soxhlet extraction method. The superoxide radical scavenging activity, nitric oxide radical, hydroxyl radical, DPPH radical and ABTS radical scavenging activity and lipid peroxidation were determined. The tumor cell suppression cell potential was determined in three different cancer cell lines MCF7 (breast cancer), HepG2 (liver cancer) and A549 (lung cancer) by SRB assay. The study showed that the methanolic extract of P. serratifolia was having free radical scavenging activity against superoxide radical, nitric oxide radical, hydroxyl radical, DPPH radical, ABTS radical and inhibition of lipid peroxidation. The IC50 value showed the efficacy was dose dependent. The test extract showed cytotoxic activity against MCF7, HepG2 and A549 cells. The GI50, TGI and LC50 values were determined against each cell line and compared with standard drug Adriamycin. The present study proved the free radical scavenging activity and tumor cell suppression potential of P. serratifolia leaf in the selective in vitro model systems. The further study has to be carried out in the aspects of isolation of functional molecules of the extract.
Antioxidants; cytotoxicity; tumor; Premna serratifolia; tumor cell
The present study evaluated the in vitro antioxidant potential of different parts of Oroxylum indicum. 2,2-diphelyl 1-picrylhydrazyl (DPPH), nitric oxide, superoxide anion and hydroxyl radical scavenging potential and reductive ability assay of methanol extract of different parts i.e. root, root bark, stem, stem bark, leaves and fruits were performed. Leaves and bark extracts exhibits highest free radical scavenging activity than bark, stem and fruit extract. Leaves extract showed maximum reductive ability and found to contain maximum amount of polyphenolic compounds. The highest free radical activity may be due to presence of polyphenolic compounds.
Free radical scavenging; Oroxylum indicum; different parts; polyphenolic compounds
Free radicals or highly reactive oxygen species are capable of inducing oxidative damage to human body. Antioxidants are the compounds which terminate the attack of reactive species and reduce the risk of diseases. Both Baccopa monnieri and Centella asiatica are used in treatment of brain disorders in humans and have almost similar effects.
The study was conducted to determine the antioxidant properties of two well-known memory enhancer medicinal plants Baccopa monnieri and Centella asiatica.
The antioxidant activity of these two medicinal plants was evaluated by measuring reducing ability, free radical scavenging activity by DPPH and hydrogen peroxide methods. The antioxidants compounds like ascorbic acid, total phenols and tannins were also evaluated in these plants. Baccopa monnieri and Centella asiatica exhibited significant differences (P<0.05) in their antioxidant values. The methanolic extract of whole leaf powder of Baccopa monnieri exhibited significantly higher antioxidant activity than the Centella asiatica. The antioxidant components viz. ascorbic acid, total phenols and tannins were also found in a higher concentration in Baccopa monnieri as compared to Centella asiatica.
It can be concluded from the study that regular use of Baccopa monnieri as a supplement could be more helpful compared to Centella asiatica in treatment of neurological disorders caused by free radical damage.
Baccopa monnieri; centella asiatica; DPPH; free radical scavenging activity; antioxidant activity; hydrogen peroxide; reducing ability
Amalakayas Rasayana (AR) is a polyherbal formulation mentioned in Ayurveda to treat aging and age-associated diseases. Being an antiaging drug, AR may have antioxidants and free radical scavenging activity to minimize free radical-induced damage which is a key cause of aging. The methanolic extract of AR was evaluated in vitro for total phenolic and tannin content, free radical scavenging activity, superoxide radical scavenging activity, and reducing power. The total phenolic content was measured using Folin-ciocalteu reagent against gallic acid [relative standard deviation (R2) = 0.998]. Total tannin was estimated using the Stephen method and was found to be 2.82% w/w. Free radical scavenging activity was measured by 2,2-diphenyl-1-picryl hydrazyl assay and R2 was 1. Superoxide radical scavenging activity was done by ethylene diamine tetra acetate and Nitro Blue Tetrazolium Chloride assays against ascorbic acid and R2 was 0.976 (EC50= 77.5 μg/ml). Ferrous reducing power was evaluated by Oyaizu method where R2 was 0.986. All studies showed that AR possesses antioxidant activity. The results of this study suggest that the antioxidant and free radical scavenging activity of AR may explain its rasayana effect and justify its use as a medicine for age associated diseases.
Antioxidant; anti-radical; Amalakayas Rasayana; DPPH; reducing power
Sonchus asper (SA) is traditionally used for the treatment of various ailments associated with liver, lungs and kidneys. This study was aimed to investigate the therapeutic potential of nonpolar (hexane, SAHE; ethyl acetate, SAEE and chloroform, SACE) and polar (methanol, SAME) crude extracts of the whole plant.
To achieve these goals, several parameters including free-radical (DPPH•, ABTS•+, H2O2 and •OH) scavenging, iron chelating activity, scavenging of superoxide radicals, total flavonoids and total phenolic content (TPC) were examined.
The SA extracts presented a remarkable capacity to scavenge all the tested reactive species with IC50 values being found at the μg ⁄ ml level. The SAME was shown to have the highest TPCs while lowest IC50 values for the DPPH•, ABTS•+ radical scavenging capacities and iron chelating scavenging efficiency, moreover, SAME had best activities in scavenging of superoxide radicals and hydrogen peroxide as well as potently scavenged the hydroxyl radicals.
These results suggest the potential of S. asper as a medicine against free-radical-associated oxidative damage.
Sonchus asper; Antioxidant activities; Solvent extraction; Phenolics
This report describes the antioxidant characteristics of methanolic extracts from broad beans (Vicia fava). The methanolic extracts of broad beans (MEBB) exhibited a marked scavenging effect on superoxide. MEBB also exerted scavenging activities on hydrogen peroxide and 1, 1-diphenyl-2-picrylhydrazyl radical. The radical scavenging activity of MEBB was highest when the scavenging effect of MEBB on Superoxide (IC50 = 0.15 mg/ml) was examined. These results suggest that MEBB have effective activities both as a radical scavenger and as a hydrogen donor. The chelating activity of MEBB (0.70 mg/ml) on Fe2+ and Cu2+ was 31.2% and 28.5%, respectively. The antioxidant effect of MEBB on lipid peroxidation might be attributed to their properties of scavenging free-radical species and their chelating activity on metal ions. The antioxidant activity of MEBB against tert-butyl hydroperoxide (BHP)-induced oxidative stress in WI-38 cells was assessed. The activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase, and glutathione peroxidase (GSH-Px) were measured as indices of oxidative stress. WI-38 cells incubated with 0.1 mM BHP for 2 hr exhibited the increase of SOD, catalase and GSH-Px activities over the control. When the cells incubated in MEBB (45–450 μg/ml) for 18 hr were subjected to a BHP challenge test, SOD activity returned to its control value or lower at all levels tested. When catalase activity was determined, a similar trend occurred except in the cells incubated in 112.5 μ g/ml MEBB. These results imply that MEBB inhibit oxidative stress in WI-38 cells.
Vicia fava; Broad beans; Methanolic extracts; Free radicals; Oxidative stress
To evaluate the free radical scavenging activity of flavonoids containing extracts of Stevia leaf. Alcoholic. Successive butanolic and alcoholic extracts of leaves were examined for free radical scavenging activity using BHT (tert-butylhydroxytolune) as a positive control by in vitro models. Successive alcoholic extract showed remarkable free radical scavenging activity. The IC50 was found to be 140 μg and 76 ig of successive alcoholic and BHT respectively in DPPH (2,2-diphenyl-1-picrylhydrazyl) assay method. The Dot-Blot test on silica layers also showed thescavenging activity of free radical of flavonoids containing extracts. The successive alcoholic extract shown significant antioxidant activity.
Antioxidant; flavonoids; Stevia and DPPH
Abelmoschus moschatus Medik. leaves and seeds are considered as valuable traditional medicine. The aromatic seeds of this plant are aphrodisiac, ophthalmic, cardio tonic, antispasmodic and used in the treatment of intestinal complaints and check queasiness. To give a scientific basis for traditional usage of this medicinal plant, the seed and leaf extracts were evaluated for their antioxidant, free radical scavenging, antimicrobial and antiproliferative activities.
In this study, antioxidant, antimicrobial and antiproliferative activities of A. moschatus extracts were evaluated in a series of in vitro assay involving free radicals, reactive oxygen species and their IC50 values were also determined. The antioxidant activities of the seed and leaf extracts of A. moschatus were determined by total antioxidant, DPPH, and ferrous reducing antioxidant property (FRAP) methods. In addition, the antiproliferative activity was also evaluated using colorectal adenocarcinoma and retinoblastoma human cancer cell lines. Moreover, six bacterial reference strains, two gram-positive (Bacillus subtilis and Staphylococcus aureus), four gram-negative (Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris and Salmonella enterica paratyphi) and one fungal strain (Candida albicans) were used to evaluate its antimicrobial activity.
The results from this study showed that the antioxidant activities of A. moschatus as determined by the total phenol, flavonoids, total antioxidant and FRAP methods were higher in leaf than that of the seed extracts. On the other hand, the aqueous overnight seed extract (AMS-I) has shown significant radical scavenging activity as in 1, 1- Diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide, hydroxyl radical, superoxide and lipid peroxidation as compared to other seed and leaf extracts. The AMS-I and AML-IV have shown activity against six and seven microorganisms respectively. Simulteneously, AMS-IV and AML-IV have demonstrated potential antiproliferative activity against two human cell lines - Colorectal adenocarcinoma (COLO-205) and retinoblastoma (Y79).
The seed and leaf extracts of A. moschatus possess significant antioxidant activity and could serve as free radical inhibitors or scavenger, or substitute, probably as primary antioxidants. The plant possesses moderate antibacterial activity against bacterial strains used in this study. Hydroalcoholic seed and leaf extracts also exhibited antiproliferative activity against two human cancer cell lines. A. moschatus may therefore, be a good candidate for functional foods as well as pharmaceutics.
The antiulcerogenic effects of the methanolic extract ofSolanum nigrum berries (SBE) on aspirin induced ulceration in rats with respect to antioxidant status in the gastric mucosa have been investigated. Oxygen free radicals are considered to be important factors in the pathogenesis of gastric ulcer. The level of lipid peroxides, which were elevated highly in rats with acute gastric mucosal injury was taken as an index of oxidative stress. The activities of antioxidant defense enzymes were also decreased considerably by oral gastric administration of aspirin. The decreased levels of antioxidant enzymes and increased mucosal injury were altered to near normal status upon pretreatment with (SBE) when compared to the ulcer induced rats. The results indicate that (SBE) may exert its gastroprotective effect by a free radical scavenging action. Our observations suggest that (SBE) may have considerable therapeutic potential in the treatment of gastric diseases.
Aspirin; Antioxidant enzymes; S. nigrum; ulcer healing
Free radical-induced oxidative stress is the root cause for many human diseases. Naturally occurring antioxidant supplements from plants are vital to counter the oxidative damage in cells. The main objective of the present study was to characterize the antioxidant and antiproliferative potential of rice bran extracted from an important Indian rice variety, Njavara and to compare the same with two commercially available basmati rice varieties: Vasumathi, Yamini and a non medicinal variety, Jyothi.
Methanolic extracts of rice bran from four varieties; Vasumathi, Yamini, Jyothi and Njavara were used to study their total phenolic and flavonoid contents, in vitro antioxidant activities including total antioxidant activity, scavenging of nitric oxide and 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical, reducing power and cytotoxic activity in C6 glioma cells. Correlation coefficient and regression analysis were done by using Sigmastat version 3.1 and Stata statistical package respectively.
Rice bran methanolic extract from Njavara showed the highest antioxidant and cell cytotoxic properties compared to the other three rice varieties. IC50 values for scavenging DPPH and nitric oxide were in the range of 30.85-87.72 μg/ml and 52.25-107.18 μg/ml respectively. Total antioxidant activity and reducing power were increased with increasing amounts of the extract. Total phenolic and flavonoid contents were in the range of 3.2-12.4 mg gallic acid-equivalent (GAE)/g bran and 1.68-8.5 mg quercetin-equivalent (QEE)/g bran respectively. IC50 values of cytotoxic assay (MTT assay) were 17.53-57.78 μg/ml. Correlation coefficient and regression analysis of phenolic content with DPPH and NO scavenging, MTT (-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay, total antioxidant assay and reducing power showed a highly significant correlation coefficient values (96-99%) and regression values (91-98%).
The results of the present study show that the crude methanolic extract from Njavara rice bran contains significantly high polyphenolic compounds with superior antioxidant activity as evidenced by scavenging of free radicals including DPPH and NO. Njavara extracts also showed highest reducing power activity, anti-proliferative property in C6 glioma cells. In conclusion, it is conceivable that the Njavara rice variety could be exploited as one of the potential sources for plant - based pharmaceutical products.
The chemopreventive effects of certain phytoconstituents can be exploited for their use as functional foods, dietary supplements and even as drugs. The natural compounds, acting as anti-genotoxic and free radical scavenging compounds, may serve as potent chemopreventive agents. These can inhibit DNA modulatory activities of mutagens and help preventing pathological processes.
Present study on Glycyrrhiza glabra L., a promising medicinal plant, widely used in traditional medicine, focused on the bioassay-guided fractionation of its extracts for the isolation of certain phytochemicals with anti-genotoxic potential against oxidative mutagens.
Materials and Methods:
The methanol extract of Glycyrrhiza glabra rhizomes was subjected to column chromatography, and isolated fraction was evaluated for its anti-genotoxic and antioxidant potential using SOS chromotest, Comet assay, and DPPH radical scavenging assay.
GLG fraction, which was characterized as Glycyrrhizic acid, inhibited the genotoxicity of oxidative mutagens viz., H2O2 and 4NQOquite efficiently. In SOS chromotest, using E.coli PQ37 tester strain, it inhibited induction factor induced by H2O2 and 4NQO by 75.54% and 71.69% at the concentration of 121.46 μM,respectively. In Comet assay, it reduced the tail moment induced by H2O2 and 4NQO by 70.21% and 69.04%, respectively, at the same concentration in human blood lymphocytes. The isolated fraction also exhibited DPPH free radical scavenging activity and was able to scavenge 85.95% radicals at a concentration of 120 μM.
Glycyrrhizic acid is a potential modulator of genotoxins as well as efficient scavenger of free radicals.
Chemoprevention; Glycyrrhiza glabra L.; glycyrrhizic acid; H2O2; oxidative mutagens; 4NQO
The powder samples and methanol extract of 11 medicinal plants were subjected to analysis of proximate composition and measurement of antioxidant activity. Different parameters studied include phenolic contents, moisture, ash, crude fiber, fats and waxes. The assays employed were ferric reducing antioxidant power, trolox equivalent antioxidant capacity and scavenging effect on the 1,1-diphenyl-2-picrylhydrazyl free radical. Results obtained indicate that the antioxidant potential varied significantly from plant to plant. The total phenolic contents were determined spectrophotometrically using Folin-Ciocalteu reagent. Significant correlation is observed between ferric reducing antioxidant power and phenolic contents (R2 = 0.96). These findings show that the polyphenolic constituents in the extracts are responsible for free radical scavenging capacity.
Antioxidant activity; ABTS; DPPH; FRAP; medicinal plants; phenolic content; proximate composition
Antioxidants are quenchers of free radical that are responsible for inducing oxidative stress generated via reactive oxygen species-induced degenerative diseases such as cancer, diabetes, and cardiovascular diseases etc. Plant and plant products are recognized as safe and potential health promoting and nutritive sources.
To investigate the antioxidant potency of polyphenol extract (PE) of Nyctanthes arbortristis leaves and identification of the active constituent by HPLC.
Materials and Methods:
PE of N. arbortristis leaves was investigated for antioxidant activity employing various established in vitro systems, such as lipid peroxidation in liposome, DPPH and hydroxyl radical scavenging, reducing power assay, and iron ion chelation. Identification of active constituent in PE of N. arbortristis responsible for antioxidant activity by HPLC. Statistical analysis used: All experiments were carried out in triplicates. Data were shown as mean ± standard deviation (SD). SPSS 10.0.5 version for windows (SPSS software Inc., USA) computer program was used for statistical analysis.
Identification of active constituent in PE revealed gallic acid 75.8 ± 0.21, protocatechuic acid 14.6 ± 0.5, chlorogenic acid 6.79 ± 0.43, and caffeic acid 5.34 ± 0.2 μg/ml. PE showed strong inhibitory activity of 73% at 200 μg/ml toward lipid peroxidation in egg lecithin, concentration-dependent inhibition of deoxyribose oxidation at 200 μg/ml was 85% inhibition, and considerable antioxidant activity in DPPH radical assay system at 200 μg/ml was 79% inhibition. BHA and gallic acid showed significant observations.
The antioxidant potency significantly correlated with the phenolic content of PE. Considering that medicinal herbs contain potent phytochemicals, which is effectively utilized for various degenerative disease, these in vitro results showed that N. arbortristis leaves could be effectively employed in functional food, to alleviate oxidative stress.
Antioxidant activity; HPLC; Nyctanthes arbortristis; polyphenol extract
We have investigated effect of Moringa oleifera leaf and fruit extracts on markers of oxidative stress, its toxicity evaluation, and correlation with antioxidant properties using in vitro and in vitro assays. The aqueous extract of leaf was able to increase the GSH and reduce MDA level in a concentration-dependent manner. The ethanolic extract of fruit showed highest phenolic content, strong reducing power and free radical scavenging capacity. The antioxidant capacity of ethanolic extract of both fruit and leaf was higher in the in vitro assay compared to aqueous extract which showed higher potential in vivo. Safety evaluation studies showed no toxicity of the extracts up to a dose of 100 mg/kg body weight. Our results support the potent antioxidant activity of aqueous and ethanolic extract of Moringa oleifera which adds one more positive attribute to its known pharmacological importance.