Showing papers on "DPPH published in 2010"
TL;DR: The results show promising perspectives for the exploitation of non-traditional tropical fruit species with considerable levels of nutrients and antioxidant capacity, as well as the considerable antioxidant capacity found for acerola – Malpighia emarginata and camu-camu – Myrciaria dubia.
1,044 citations
TL;DR: In this paper, the antioxidant activity of resveratrol was investigated by employing various in vitro assays such as DPPH•, ABTS•, DMPD•+, O2•− and H2O2 scavenging activities, total antioxidant activity, reducing abilities, and Fe2+ chelating activities.
Abstract: Resveratrol, a natural product, is known to affect a broad range of intracellular mediators. In the present study, we clarified the antioxidant activity of resveratrol by employing various in vitro antioxidant assays such as DPPH•, ABTS•+, DMPD•+, O2•− and H2O2 scavenging activities, total antioxidant activity, reducing abilities, and Fe2+ chelating activities. Resveratrol inhibited 89.1% of the lipid peroxidation of linoleic acid emulsion at 30 µg/mL concentration. On the other hand, BHA, BHT, α-tocopherol, and trolox exhibited inhibitions of 83.3, 82.1, 68.1, and 81.3% against peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, resveratrol had effective DPPH•, ABTS•+, DMPD•+, O2•− and H2O2 scavenging activities, reducing power, and Fe2+ chelating activities. The present study found that resveratrol had effective in vitro antioxidant and radical scavenging activity. It can be used in pharmacological and food industry due to its antioxidant properties. Industrial relevance Antioxidants are often added to foods to prevent the radical chain reactions of oxidation and they act by inhibiting the initiation and propagation step leading to the termination of the reaction and delay the oxidation process. At the present time, the most commonly used antioxidants are BHA, BHT, propylgallate and tert-butyl hydroquinone. Besides that BHA and BHT are restricted by legislative rules because of doubts over their toxic and carcinogenic effects. Therefore, there is a growing interest on natural and safer antioxidants in food applications, and a growing trend in consumer preferences for natural antioxidants, all of which has given more impetus to explore natural sources of antioxidants. A variety of foods and beverages of vegetable origin contain several nonflavonoid classes of phenolic compounds synthesized by plants. Among them, resveratrol has been identified as the major active compound of stilbene phytoalexins and is presumed to be beneficial for human health. Resveratrol is naturally occurring in the fruits and leaves of edible plants, peanuts, mulberries, grapes and red wine. Resveratrol is currently in the limelight all over the world due to their beneficial effects on the human body. Resveratrol can be used for minimizing or preventing lipid oxidation in pharmaceutical products, retarding the formation of toxic oxidation products, maintaining nutritional quality and prolonging the shelf life of food products and pharmaceuticals instead of BHA and BHT and other antioxidant compounds because of their safer usage.
697 citations
TL;DR: 6-Shogaol has exhibited the most potent antioxidant and anti-inflammatory properties which can be attributed to the presence of alpha,beta-unsaturated ketone moiety, and this study justifies the use of dry ginger in traditional systems of medicine.
559 citations
TL;DR: The medicinal potential of the leaves and young rhizome of Halia Bara is validated and the positive relationship between total phenolics content and antioxidant activities in Zingiber officinale is validated.
Abstract: Ginger (Zingiber officinale Roscoe) is a well known and widely used herb, especially in Asia, which contains several interesting bioactive constituents and possesses health promoting properties. In this study, the antioxidant activities of methanol extracts from the leaves, stems and rhizomes of two Zingiber officinale varieties (Halia Bentong and Halia Bara) were assessed in an effort to compare and validate the medicinal potential of the subterranean part of the young ginger. The antioxidant activity and phenolic contents of the leaves as determined by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay and the total amounts of phenolics and flavonoids were higher than those of the rhizomes and stems. On the other hand, the ferric reducing/antioxidant potential (FRAP) activity of the rhizomes was higher than that of the leaves. At low concentration the values of the leaves' inhibition activity in both varieties were significantly higher than or comparable to those of the young rhizomes. Halia Bara had higher antioxidant activities as well as total contents of phenolic and flavonoid in comparison with Halia Bentong. This study validated the medicinal potential of the leaves and young rhizome of Zingiber officinale (Halia Bara) and the positive relationship between total phenolics content and antioxidant activities in Zingiber officinale.
503 citations
TL;DR: Evidence is provided that the crude aqueous extract of H. longifolium is a potential source of natural antioxidants, and this justified its uses in folkloric medicines.
Abstract: Many oxidative stress related diseases are as a result of accumulation of free radicals in the body. A lot of researches are going on worldwide directed towards finding natural antioxidants of plants origins. The aims of this study were to evaluate in vitro antioxidant activities and to screen for phytochemical constituents of Helichrysum longifolium DC. [Family Asteraceae] aqueous crude extract. We assessed the antioxidant potential and phytochemical constituents of crude aqueous extract of Helichrysum longifolium using tests involving inhibition of superoxide anions, DPPH, H2O2, NO and ABTS. The flavonoid, proanthocyanidin and phenolic contents of the extract were also determined using standard phytochemical reaction methods. Phytochemical analyses revealed the presence of tannins, flavonoids, steroids and saponins. The total phenolic content of the aqueous leaf extract was 0.499 mg gallic acid equivalent/g of extract powder. The total flavonoid and proanthocyanidin contents of the plant were 0.705 and 0.005 mg gallic acid equivalent/g of extract powder respectively. The percentage inhibition of lipid peroxide at the initial stage of oxidation showed antioxidant activity of 87% compared to those of BHT (84.6%) and gallic acid (96%). Also, the percentage inhibition of malondialdehyde by the extract showed percentage inhibition of 78% comparable to those of BHT (72.24%) and Gallic (94.82%). Our findings provide evidence that the crude aqueous extract of H. longifolium is a potential source of natural antioxidants, and this justified its uses in folkloric medicines.
444 citations
TL;DR: In this article, the authors showed that sardinelle by-products protein hydrolysates are a good source of natural antioxidants, and they identified seven antioxidant peptides from Sardina pilchardus.
413 citations
01 Jan 2010
TL;DR: Methanol extract of the whole plant of Oxalis corniculata Linn (Family: Oxalidaceae) was assessed for its antioxidant and anti-inflammatory activity by using in-vitro methods.
Abstract: Methanol extract of whole plant of Oxalis corniculata Linn (Family: Oxalidaceae) was assessed for its antioxidant and anti‐inflammatory activity by invitro methods. Antioxidant activity was studied using 1, 1‐Diphenyl‐2‐Picrylhydrazyl (DPPH) and nitric oxide radical scavenging activity. Inhibition of lipid peroxidation was studied by thiobarbituric acid reactive substances (TBARS) method on isolated rat liver tissues. Quantitative analysis of antioxidative components like total amount of phenolics, flavonoids and flavonols were estimated using spectrophotometric method. Invitro anti‐inflammatory activity was evaluated using albumin denaturation assay, membrane stabilization assay and proteinase inhibitory activity at different concentrations. Aspirin was used as a sta ndard drug for the study of anti‐ inflammatory activity. Linear regression analysis was used to calculate IC50 value. Results showed that, the extract exhibited significant DPPH and nitric oxide radical scavenging activity with IC50 v alue of 302.93±4.17 and 73.07±8.28µg/ml respectively. Lipid peroxidation induced by the Fe2+, was inhibited by the extract with IC50 value 58.71±2.55µg/ml. Total phenol content was estimated as 25.62±0.10mg of gallic acid equivalents of dry extract. Total flavonoids and flavonols were found to be 150.88±12.61 and 150.16±2.16 mg of rutin equivalents per gram of dry extract respectively. Extract also showed invitro anti‐inflammatory activity by inhibiting the heat induced albumin denaturation and Red Blood Cells membrane stabilization with the IC50 values of 288.04±2.78 and 467.14±9.56µg/ml respectively. Proteinase activity was also significantly inhibited by the extract (IC50=435.28±5.82µg/ml). From the results, it is concluded that flavonoids and related polyphenols present in the O. corniculata extract may be responsible for the activity.
383 citations
TL;DR: In this paper, the physicochemical and antioxidant properties of some commercial brands of Indian honeys have been investigated with respect to their level of total phenolics, protein, radical scavenging activity, ascorbic acid equivalent antioxidant content (AEAC) and ferric reducing antioxidant potential (FRAP).
375 citations
TL;DR: Fermentation offers a tool to further increase the bioactive potential of cereal products by enhancing levels of antioxidant activity and total phenolic content.
354 citations
TL;DR: In this article, the authors determined polyphenolic composition, related antioxidative and antimicrobial properties of grape skin extracts from 14 grape varieties (seven white and seven red grape) grown in Dalmatia (Croatia).
352 citations
TL;DR: In this paper, a study was carried out for identification of the phytochemicals present in the Vitex negundo leaves and also evaluate the total phenols, total flavonoids and antioxidant activity of the leaf extract.
Abstract: The present study was carried out for identification of the phytochemicals present in the Vitex negundo leaves and also evaluate the total phenols, total flavonoids and antioxidant activity of the leaf extract. Total phenols was carried out by Folin Ciocalteu method and the phenolic content was 27.72 mg/100 of gallic acid equivalent (GE). Antioxidant activity was evaluated by DPPH method and the leaves of V. negundo showed 23.21 mg/100 of ascorbic acid equivalent antioxidant capacity (AEAC). The GC-MS study also carried out and it showed the presence of phytochemicals like 4H-Pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl-(RT:6.17), Phytol (RT:19.67) and Vitamin E (RT:25.11).
Key words: Total Phenols, total flavonoids, antioxidant activity, DPPH, GC-MS.
TL;DR: Banana (Musa acuminata Colla AAA) peel extracts obtained in this work had a high capacity to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2′-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS +) free radicals, and they were also good lipid peroxidation inhibitors as discussed by the authors.
TL;DR: In this paper, a preparative column chromatography method was developed to isolate carotenoids, flavonoids and polysaccharides, from Lycium barbarum L, possessing vital biological activity, and their antioxidant activity was evaluated.
TL;DR: Vegetable extracts from Indonesian origin were screened for flavonoid content, total phenolics, and antioxidant activity and were identified as potentially rich sources of dietary flavonoids and antioxidants.
TL;DR: In this article, the effect of flavonoid interactions on their antioxidant power was evaluated by two different in vitro tests: DPPH radical scavenging activity and ferric reducing antioxidant power (FRAP).
TL;DR: The chloroform and aqueous fractions of Carissa opaca fruit, a traditional medicinal fruit in Pakistan possessed a high amount of total phenolic and flavonoid contents as compare to other solvent fractions with potent antioxidant activities in scavenging DPPH, superoxides, hydroxyl, hydrogen peroxide, ABTS radicals, and had strong iron chelating activity as discussed by the authors.
TL;DR: In this paper, four fractions, namely, rice bran, rice husk, brown rice and milled rice of a Thai rice variety (Khao Dawk Mali 105), collected from three different growth sites, were analyzed to determine phenolic acid composition, γ-oryzanol and tocopherols content and their antioxidant capacity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric reducing ability power (FRAP) assays.
TL;DR: It seemed that geographical variation might have influenced the oil compounds either quantitatively or qualitatively as well as qualitative similarities among the oils from different origins.
TL;DR: In vitro antioxidant activities and protective effects in stabilising sunflower oil of three rosemary extracts high in carnosic acid (CA) were tested in this paper, which indicated that CA exhibited stronger antioxidant activity than BHT and BHA, but its antioxidant activity was less than that of TBHQ.
TL;DR: The EOs were found non-mammalian toxic showing high LD(50) for mice (oral, acute) and may be recommended as safe plant based antimicrobials as well as antioxidants for enhancement of shelf life of food commodities by checking their fungal infestation, aflatoxin production as wellAs lipid peroxidation.
TL;DR: In this article, the antioxidant activity of essential oils from several spices widely used in Mediterranean countries was tested: oregano (Origanum vulgare), thyme (Thymus vulgaris), rosemary (Rosmarinus officinalis), sage (Salvia officinalsis), and clove (Syzygium aromaticum).
Abstract: The oxidative degradation of lipids is one of the main factors limiting the shelf-life of food products. In recent years, several undesirable disorders have been detected as side-effects of using commonly used synthetic antioxidants. Apart from their use as aroma additives in food, essential oils from aromatic plants have shown potential for use in small amounts in fat-containing food systems to prevent or delay some types of chemical deterioration that occur during storage. Using a multiple-method approach, the antioxidant activity of the essentials oils from several spices widely used in Mediterranean countries was tested: oregano (Origanum vulgare), thyme (Thymus vulgaris), rosemary (Rosmarinus officinalis), sage (Salvia officinalis) and clove (Syzygium aromaticum). Their total phenolic compound content was also determined. The clove essential oil had the highest amount of total phenols (898.89 mg/l GAE) and showed the highest percentage inhibition of DPPH radical (98.74%) and the highest FRAP value (1.47 TEAC). The thyme essential oil produced the highest percentage inhibition of TBARS (89.84%). All the essential oils studied were capable of chelating iron(II), the rosemary essential oil producing the highest effect (76.06%) in this respect. The oregano essential oil had the highest antioxidant activity index in the Rancimat test. Copyright © 2009 John Wiley & Sons, Ltd.
TL;DR: The results suggest that both ginger and cumin can be used as potential sources of natural antioxidants in foods.
Abstract: Spices are the building blocks of flavor in foods. This research work was focused on two important spices, i.e., ginger and cumin. Ginger and cumin both are recognized for their antioxidant properties. So, this study was designed to evaluate the chemical composition and antioxidant activity of ginger (Zingiber officinale) and cumin (Cuminum cyminum). The highest yield for volatile oil was obtained by the cumin sample, which was 2.52 +/- 0.11%, while the fresh ginger showed the lowest yield (0.31 +/- 0.08%). The analysis of volatile oils of fresh and dried ginger showed camphene, p-cineole, alpha-terpineol, zingiberene and pentadecanoic acid as major components, while the major components in cumin volatile oil were cuminal, gamma-terpinene and pinocarveol. In nonvolatile extracts the highest yield was obtained by the methanol extract of cumin (4.08 +/- 0.17% w/w), while the n-hexane extract of fresh ginger showed the lowest yield (0.52 +/- 0.03% w/w). Maximum total phenolic contents were observed in the methanol extract of fresh ginger (95.2 mg/g dry extract) followed by the hexane extract of fresh ginger (87.5 mg/g dry extract). The hexane extract of cumin showed the lowest total phenolic content (10.6 mg/g dry extract). The DPPH method showed the highest antioxidant activity for cumin essential oil (85.44 +/- 0.50%) followed by dried ginger essential oil (83.87 +/- 0.50%) and fresh ginger essential oil (83.03 +/- 0.54%). The FRAP of essential oils showed almost comparative results with DPPH. Cumin essential oil was found best in reducing Fe(3+) ions, followed by dried and fresh ginger. Our results suggest that both ginger and cumin can be used as potential sources of natural antioxidants in foods.
TL;DR: A water-soluble polysaccharide was isolated from the water extract of Cyclocarya paliurus (Batal.) Iljinskaja, which is a well-known native health tea in China as discussed by the authors.
TL;DR: The results obtained herein strongly indicate that walnut tree constitute an excellent source of effective natural antioxidants and chemopreventive agents.
TL;DR: In this article, the antioxidant and antiproliferative properties of the flesh and peel of mango (Mangifera indica L) were investigated. And the results showed that mango peel extract exhibited stronger free radical scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and alkyl radicals than mango flesh extract regardless of ripeness.
TL;DR: The study revealed that phenolic, in particular flavonoids, may be the main contributors to the antioxidant activity exhibited by the plants and has great potential to be used in the development of functional ingredients/foods that are currently in demand for the health benefits associated with their use.
Abstract: UNLABELLED Free radical scavenging activity of 21 tropical plant extracts was evaluated using 1,1-diphenyl-2-picrylhydrazyl assay (DPPH). Total phenolic compounds and flavonoids were determined using Folin-Ciocalteu and HPLC, respectively. Results of the study revealed that all the plants tested exhibited excellent antioxidant activity with IC(50) in the range of 21.3 to 89.6 microg/mL. The most potent activity was demonstrated by Cosmos caudatus (21.3 microg/mL) and Piper betle (23.0 microg/mL) that are not significantly different than that of -tocopherol or BHA. L. inermis extract was found to consist of the highest concentration of phenolics, catechin, epicatechin, and naringenin. High content of quercetin, myricetin, and kaempferol were identified in Vitex negundo, Centella asiatica, and Sesbania grandiflora extracts, respectively. Luteolin and apigenin, on the other hand, were found in Premna cordifolia and Kaempferia galanga extracts. Strong correlation (R = 0.8613) between total phenolic compounds and total flavonoids (R = 0.8430) and that of antioxidant activity of the extracts were observed. The study revealed that phenolic, in particular flavonoids, may be the main contributors to the antioxidant activity exhibited by the plants. PRACTICAL APPLICATION Potent antioxidant from natural sources is of great interest to replace the use of synthetic antioxidants. In addition, some of the plants have great potential to be used in the development of functional ingredients/foods that are currently in demand for the health benefits associated with their use.
TL;DR: In this paper, the authors determined the antioxidant capacities, phenolic content, and procyanidins in avocados of different strains and cultivars using HPLC-MSn.
TL;DR: Results suggest that the crude polysaccharide of T.ornata could be considered as a potential antioxidant and anti-inflammatory agent.
TL;DR: 3s was obtained as lead compound with promising anticancer, anti-inflammatory and antioxidant activities and was confirmed to be nontoxic by in vitro cytotoxicity study.
TL;DR: The QSAR models developed here can be utilised for the antioxidant activity prediction of a new series of molecules, indicating the predictivity and robustness, respectively, of the developed models.
Abstract: In the present work, quantitative structure–activity relationship (QSAR) models have been built for a wide variety of antioxidant phenolic compounds obtained from traditional Chinese medicinal plants, with their Trolox equivalent antioxidant capacity measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) radical (ABTS√+) assay methods. Non-linear models obtained using genetic partial least-squares technique were acceptable both in terms of internal and external predictivity. Validation of developed models using metrics and randomisation technique yielded results indicating the predictivity and robustness, respectively, of the developed models. The models signify that the presence of ketonic oxygen within the molecular structure favours their antioxidant activity. In addition, the number of hydroxyl groups, extent of branching, degree of methoxylation and the number of methyl and methylene substituents also dictate the antioxidant activity of...