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Showing papers on "DPPH published in 2012"


Journal ArticleDOI
TL;DR: The most commonly methods used in vitro determination of antioxidant capacity of food constituents are reviewed and presented, and the general chemistry underlying the assays in the present paper was clarified.
Abstract: Recently, there has been growing interest in research into the role of plant-derived antioxidants in food and human health. The beneficial influence of many foodstuffs and beverages including fruits, vegetables, tea, coffee, and cacao on human health has been recently recognized to originate from their antioxidant activity. For this purpose, the most commonly methods used in vitro determination of antioxidant capacity of food constituents are reviewed and presented. Also, the general chemistry underlying the assays in the present paper was clarified. Hence, this overview provides a basis and rationale for developing standardized antioxidant capacity methods for the food, nutraceutical, and dietary supplement industries. In addition, the most important advantages and shortcomings of each method were detected and highlighted. The chemical principles of these methods are outlined and critically discussed. The chemical principles of methods of 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonate) radical (ABTS·+) scavenging, 1,1-diphenyl-2-picrylhydrazyl (DPPH·) radical scavenging, Fe3+–Fe2+ transformation assay, ferric reducing antioxidant power (FRAP) assay, cupric ions (Cu2+) reducing power assay (Cuprac), Folin-Ciocalteu reducing capacity (FCR assay), peroxyl radical scavenging, superoxide anion radical (O 2 ·− ) scavenging, hydrogen peroxide (H2O2) scavenging, hydroxyl radical (OH·) scavenging, singlet oxygen (1O2) quenching assay and nitric oxide radical (NO·) scavenging assay are outlined and critically discussed. Also, the general antioxidant aspects of main food components were discussed by a number of methods which are currently used for detection of antioxidant properties food components. This review consists of two main sections. The first section is devoted to main components in the foodstuffs and beverages. The second general section is some definitions of the main antioxidant methods commonly used for determination of antioxidant activity of components in the foodstuffs and beverages. In addition, there are given some chemical and kinetic basis and technical details of the used methods.

1,278 citations


Journal ArticleDOI
TL;DR: In this article, a detailed kinetic study of antioxidants has been performed and comprehensive results in terms of effective concentration which scavenges 50% radical (EC 50 ), antioxidant reducing power (ARP), stoichiometry and second order rate constant (k 2 ) values have been reported with DPPH assay.

754 citations


Journal ArticleDOI
TL;DR: Data from present results revealed that Torilis leptophylla act as an antioxidant agent due to its free radical scavenging and cytoprotective activity.
Abstract: The aim of this study was to screen various solvent extracts of whole plant of Torilis leptophylla to display potent antioxidant activity in vitro and in vivo, total phenolic and flavonoid contents in order to find possible sources for future novel antioxidants in food and pharmaceutical formulations. A detailed study was performed on the antioxidant activity of the methanol extract of whole plant of Torilis leptophylla (TLM) and its derived fractions {n-hexane (TLH), chloroform (TLC) ethyl acetate (TLE) n-butanol (TLB) and residual aqueous fraction (TLA)} by in vitro chemical analyses and carbon tetrachloride (CCl4) induced hepatic injuries (lipid peroxidation and glutathione contents) in male Sprague-Dawley rat. The total yield, total phenolic (TPC) and total flavonoid contents (TFC) of all the fractions were also determined. TLM was also subjected to preliminary phytochemical screening test for various constituents. The total phenolic contents (TPC) (121.9±3.1 mg GAE/g extract) of TLM while total flavonoid contents (TFC) of TLE (60.9 ±2.2 mg RTE/g extract) were found significantly higher as compared to other solvent fractions. Phytochemical screening of TLM revealed the presence of alkaloids, anthraquinones, cardiac glycosides, coumarins, flavonoids, saponins, phlobatannins, tannins and terpenoids. The EC50 values based on the DPPH (41.0±1 μg/ml), ABTS (10.0±0.9 μg/ml) and phosphomolybdate (10.7±2 μg/ml) for TLB, hydroxyl radicals (8.0±1 μg/ml) for TLC, superoxide radicals (57.0±0.3 μg/ml) for TLM and hydrogen peroxide radicals (68.0±2 μg/ml) for TLE were generally lower showing potential antioxidant properties. A significant but marginal positive correlation was found between TPC and EC50 values for DPPH, hydroxyl, phosphomolybdate and ABTS, whereas another weak and positive correlation was determined between TFC and EC50 values for superoxide anion and hydroxyl radicals. Results of in vivo experiment revealed that administration of CCl4 caused a significant increase in lipid peroxidation (TBARS) while decrease in GSH contents of liver. In contrast, TLM (200 mg/kg bw) and silymarin (50 mg/kg bw) co-treatment effectively prevented these alterations and maintained the antioxidant status. Data from present results revealed that Torilis leptophylla act as an antioxidant agent due to its free radical scavenging and cytoprotective activity.

723 citations


Journal ArticleDOI
TL;DR: In this paper, clove oil was evaluated by employing various in vitro antioxidant assay such as α,α-diphenyl-β-picryl-hydrazyl free radical (DPPH) scavenging, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity.

351 citations


Journal ArticleDOI
TL;DR: Exotic fruit fibres obtained as co-products in the process to obtain juice may be considered a good source of natural compounds with significant antioxidant activity and a good correlation between total phenol content and antioxidant capacity.

324 citations


Journal ArticleDOI
TL;DR: L. plantarum C88 isolated from traditional Chinese fermented dairy tofu could be considered as a potential antioxidant to be applied in functional foods.

303 citations


Journal ArticleDOI
TL;DR: In this article, two essential oils (EOs), thymol and carvacrol, with similar chemical structures were encapsulated in the nanoparticles of zein using the liquid-liquid dispersion method.
Abstract: Two essential oils (EOs), thymol and carvacrol, with similar chemical structures were encapsulated in the nanoparticles of zein using the liquid–liquid dispersion method. Three different pH treatments were applied to study the nanoparticles' morphology, structure, antioxidant property, and antimicrobial activity. The nanoparticles for all treatments were well dispersed in water. After lyophilizing, samples from the acidic condition tended to form film, but the samples from the neutral and basic conditions formed nanoparticles. The antioxidant properties were analyzed by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and Ferric ion spectrophotometric assay. DPPH was reduced in the range of 24.8–66.8% depending on the formulation and more than 65% hydroxyl free radicals were quenched by samples. An Escherichia coli reduction of 0.8–1.8 log CFU/ml was achieved in the presence of nanoparticles encapsulating EOs.

302 citations


Journal ArticleDOI
TL;DR: The light blue ZPP-2 selfed maize genotype has a higher content of total phenolics, flavonoids, and ferulic acid as compared to other tested maize and the highest ABTS radical scavenging activity.
Abstract: In this study, the contents of total phenolics, flavonoids, anthocyanins, β-carotene, and lutein as well as free, conjugated, and insoluble bound phenolic acids were determined in whole kernels of 10 different colored maize genotypes. In addition, the antioxidant activity was evaluated as radical scavenging activity with ABTS (2,2-azino-bis/3-ethil-benothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) reagents. Generally, considerable differences in phytochemical contents and antioxidant capacity were observed between the genotypes. The β-carotene and lutein contents ranged from 0 to 2.42 mg/kg d.m. and from 0 to 13.89 mg/kg d.m., respectively, whereas the total anthocyanin contents of anthocyanin-rich colored maize genotypes ranged from 2.50 to 696.07 mg CGE/kg d.m. (cyanidin 3-glucoside equivalent) with cyanidin 3-glucoside (Cy-3-Glu) as the most dominant form. The light blue ZPP-2 selfed maize genotype has a higher content of total phenolics, flavonoids, and ferulic acid as compared to other tested maize and the highest ABTS radical scavenging activity.

283 citations


Journal ArticleDOI
TL;DR: The high-throughput 96-well plate method proved to be as robust and reproducible as the conventional method for determining total phenolic content, flavonoid content and DPPH-scavenging capacity in either sorghum bran or flour.
Abstract: BACKGROUND: Sorghum possesses phenolic compounds that are health-promoting constituents of the grain. There are approximately40000sorghumaccessions, manyofwhichhavenotbeenevaluatedforthegrain’shealth-promotingpotential. Conventional methods for measuring total phenolic content, flavonoid content and 2,2-diphenyl-1-picrylhydrazyl (DPPH)scavenging capacity are time-consuming and labour-intensive, resulting in low overall throughput. The objective of this study was to develop a high-throughput screening assay for large sorghum sample sets to determineflavonoid and phenolic content and to modify existing DPPH and total phenolic assays. RESULTS: The 96-well assays exhibited a correlation of >0.9 with the conventional assays. The 96-well assays allowed for up to 64 samples to be run per day compared with 20‐24 samples (depending on the test) for the conventional methods. The 96-well assays had excellent accuracy (97.65‐106.16% recovery), precision (1.06‐8.28% coefficient of variation (CV)) and reproducibility (1.32‐2.13% CV inter-day and 1.36‐2.09% CV intra-day).

272 citations


Journal ArticleDOI
TL;DR: The results indicate that the phenolics, flavonoids and trace metals play an important role in the antioxidant activities of medicinal plants.
Abstract: The main aim of this study is to evaluate the antioxidant and anti-inflammatory properties of forty four traditional Chinese medicinal herbal extracts and to examine these activities in relation to their antioxidant content The antioxidant activities were investigated using DPPH radical scavenging method and yeast model The anti-inflammatory properties of the herbal extracts were evaluated by measuring their ability to inhibit the production of nitric oxide and TNF-α in RAW 2647 macrophages activated by LPS and IFN- γ, respectively The cytotoxic effects of the herbal extracts were determined by Alomar Blue assay by measuring cell viability In order to understand the variation of antioxidant activities of herbal extracts with their antioxidant contents, the total phenolics, total flavonoids and trace metal (Mg, Mn, Cu, Zn, Se and Mo) quantities were estimated and a correlation analysis was carried out Results of this study show that significant levels of phenolics, flavonoids and trace metal contents were found in Ligustrum lucidum, Paeonia suffuticosa, Salvia miltiorrhiza, Sanguisorba officinalis, Spatholobus suberectus, Tussilago farfara and Uncaria rhyncophylla, which correlated well with their antioxidant and anti-inflammatory activities Some of the plants displayed high antioxidant and anti-inflammatory activities but contained low levels of phenolics and flavonoids Interestingly, these plants contained significant levels of trace metals (such as Zn, Mg and Se) which are likely to be responsible for their activities The results indicate that the phenolics, flavonoids and trace metals play an important role in the antioxidant activities of medicinal plants Many of the plants studied here have been identified as potential sources of new antioxidant compounds

263 citations


Journal ArticleDOI
TL;DR: Results showed that there is no correlation between the studied commercial mushrooms and the corresponding mycelia obtained in vitro, and this study contributes to the rise of data relatively to the species consumed as fresh mushroom and the possibility of their in vitro production as a source of bioactive compounds.

Journal ArticleDOI
TL;DR: In this paper, the influence of various parameters (time and temperature of extraction, solvent composition, solid-solvent ratio, particle size, and ultrasonic irradiations) on the extraction kinetics and yields was evaluated.

Journal ArticleDOI
TL;DR: The present study suggests that M. oleifera could be a potential source of compounds with strong antioxidant potential and the reducing power of both solvent extracts showed strong antioxidant activity in a concentration dependent manner.

Journal ArticleDOI
TL;DR: In this paper, the authors used electron paramagnetic resonance (EPR) spectroscopy to determine the bioaccessibility of five millet varieties (kodo, finger, proso, foxtail and pearl) under physiological conditions.

Journal ArticleDOI
TL;DR: A process for the effective extraction and fractionation of phlorotannins from Fucus vesiculosus with high antioxidant potentials was investigated, finding no clear relationships between the degree of polymerization, molecular size, and antioxidant activity.
Abstract: A process for the effective extraction and fractionation of phlorotannins from Fucus vesiculosus with high antioxidant potentials was investigated. The antioxidant activity of F. vesiculosus extract/fractions was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, reducing power, and ferrous ion-chelating assays. Among the crude extract and different polarity fractions, the phlorotannin-enriched ethyl acetate fraction possessed the highest DPPH scavenging activity and reducing power. This fraction was further fractionated by Sephadex LH-20 column chromatography or ultrafiltration. The antioxidant properties were evaluated by both the above chemical antioxidant tests and a mononuclear cell-based bioassay. Sephadex subfractions LH-2 and LH-3 with high total phlorotannin content exhibited strong DPPH quenching activity, comparable to those of ascorbic acid and butylated hydroxytoluene and significantly higher than that of α-tocopherol. Polyphenols in F. vesiculosus were found to consist mainly of high molecular weight phlorotannin polymers. There were no clear relationships between the degree of polymerization, molecular size, and antioxidant activity. All the subfractions separated by Sephadex LH-20 column chromatography and ultrafiltration showed a high ability to scavenge reactive oxygen species generated by mononuclear cells. Further characterization of the phlorotannin compounds was performed on six Sephadex subfractions. Several phlorotannin oligomers were tentatively identified on the basis of HPLC-ESI-MS(n) analyses.

Journal ArticleDOI
TL;DR: AAcidS, AAcidG, SodAsS, SodasG and VitE presented the highest antioxidant activity among substances tested in this study, and the DPPH assay provides an easy and rapid way to evaluate potential antioxidants.
Abstract: The aim of this study was to assess, using the DPPH assay, the antioxidant activity of several substances that could be proposed to immediately revert the problems caused by bleaching procedures. The percentage of antioxidant activity (AA%) of 10% ascorbic acid solution (AAcidS), 10% ascorbic acid gel (AAcidG), 10% sodium ascorbate solution (SodAsS), 10% sodium ascorbate gel (SodAsG), 10% sodium bicarbonate (Bicarb), Neutralize(®) (NE), Desensibilize(®) (DES), catalase C-40 at 10 mg/mL (CAT), 10% alcohol solution of alpha-tocopherol (VitE), Listerine(®) (LIS), 0.12% chlorhexidine (CHX), Croton Lechleri (CL), 10 % aqueous solution of Uncaria Tomentosa (UT), artificial saliva (ArtS) and 0.05% sodium fluoride (NaF) was assessed in triplicate by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical assay. All substances exhibited antioxidant activity, except for CL. AAcidS, AAcidG and VitE exhibited the highest AA% (p<0.05). On the contrary, CHX, NE, LIS and NaF showed the lowest AA% (p<0.05). In conclusion, AAcidS, AAcidG, SodAsS, SodAsG and VitE presented the highest antioxidant activity among substances tested in this study. The DPPH assay provides an easy and rapid way to evaluate potential antioxidants.

Journal ArticleDOI
TL;DR: In this article, the antioxidant activity of fruit juices was shown to be directly related to the content of ascorbic acid and total phenolics except in case of C. aurantium.
Abstract: The ascorbic acid and total phenolic content to antioxidant activity of fresh juices of four ripe and unripe citrus fruits namely Citrus limon , C. reticulata , C. sinensis and C. aurantium were compared. The fruits were collected from local market and the pulp and seed free juices were collected. The pH and total acidity were determined. Ascorbic acid content and total phenolic content of fresh fruit juices were determined by volumetric and Folin-Ciocalteu reagent method respectively. Antioxidant activity of fruit juices was determined by two in vitro assays namely DPPH free radical scavenging assay and Ferric reducing assay. The pH was lesser in unripe fruit juices. Acidity, ascorbic acid and total phenolic contents were high in unripe fruit juices. Ascorbic acid and total phenolic content was high in C. aurantium and C. sinensis respectively. In DPPH assay, C. limon , C. reticulata and C. sinensis exhibited stronger scavenging potential when compared to C. aurantium . Ferric reducing potential was higher in C. sinensis followed by others. Overall, unripe fruit juices have displayed stronger antioxidant activity when compared to ripe fruit juices. In this study, the antioxidant activity of fruit juices was shown to be directly related to the content of ascorbic acid and total phenolics except in case of C. aurantium . The lower antioxidant activity of ripe fruit juices could be due to the possible reduction in the ascorbic acid and total phenolic content during ripening.

Journal ArticleDOI
TL;DR: In this article, the authors investigated the antioxidant properties of 12 vegetables (carrots, cabbage, cauliflower, potatoes, onions, asparagus and eggplant) for their total anthocyanin contents (TAC) and compositions of the individual Anthocyanins and delphinidins and their antioxidant activities by DPPH, FRAP (ferric reducing antioxidant power) and ORAC (oxygen radical absorption capacity).

Journal ArticleDOI
TL;DR: In this paper, the authors reported on the anthocyanin and antioxidant contents, an the "in vitro" antiproliferative and "in vivo" mutagenic/antimutagenic activities of freeze-dried jaboticaba peel (JP).

Journal ArticleDOI
TL;DR: This novel extraction method was used to isolate polysaccharides from Cyclocarya paliurus (Batal.) Iljinskaja, and response surface methodology (RSM) was employed to optimize the extraction conditions.

Journal ArticleDOI
TL;DR: In this article, the authors quantified polyphenols from the flesh and peels of red pitaya (Hylocereus polyrhizus) fruit by employing an extract sub-fractionation procedure applied for the first time to this fruit.

Journal ArticleDOI
Wei-Cai Zeng1, Zeng Zhang1, Hong Gao1, Li-Rong Jia1, Wu-Yong Chen1 
TL;DR: It is suggested that Auricularia auricula by MAE had low molecular weight and remarkable antioxidant capability.

Journal ArticleDOI
TL;DR: The first report of antimicrobial activity of essential oil of Artemisia annua against Haemophilus influenzae, Enterococcus faecalis, Streptococcus pneumoniae, Micrococcus luteus and Candida krusei microbial strains is presented in this article.

Journal ArticleDOI
TL;DR: The potential of S. asper as a medicine against free-radical-associated oxidative damage is suggested and the SAME had best activities in scavenging of superoxide radicals and hydrogen peroxide as well as potently scavenged the hydroxyl radicals.
Abstract: 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.

Journal ArticleDOI
TL;DR: In this article, tomato processing byproducts, together with unprocessed tomatoes were analyzed for several bioactive phytochemicals, like sterols, tocopherols, carotenes, terpenes, total and simple polyphenols.
Abstract: Tomato processing byproducts, together with unprocessed tomatoes were analyzed for several bioactive phytochemicals, like sterols, tocopherols, carotenes, terpenes, total and simple polyphenols. In addition, their radical scavenging capacity and reducing power were assayed. On a dry weight (DW) basis, tomato wastes contained significantly lower amounts of lycopene and increased amounts of β-carotene, tocopherols, sterols and terpenes, while their fatty acid profile was similar to that of unprocessed tomatoes. Tomato byproducts contained similar amount of total polyphenols and exhibited similar DPPH radical scavenging activity and ferric reducing power with tomatoes. Among 18 simple polyphenols determined by GC/MS, hydroxycinnamic acids predominated in whole tomatoes, while flavonoids predominated in tomato wastes with naringenin comprising 87% of flavonoids. As most of the phytochemicals determined exert antioxidant activities, tomato processing byproducts could be successfully utilized as functional ingredient for the formulation of antioxidant rich functional foods.

Journal ArticleDOI
TL;DR: In this paper, three polysaccharides (GLP-H, GLP-V and GlP-F) were obtained from Ganoderma lucidum by hot air drying, vacuum drying and vacuum freeze drying, respectively.

Journal ArticleDOI
TL;DR: The findings suggest that Capsicum baccatum contains potential antioxidant and anti-inflammatory compounds which could be tested as drug candidates against oxidative and inflammation-related pathological processes in medicinal chemistry studies.

Journal ArticleDOI
TL;DR: In this article, a central composite design (CCD) and response surface methodology (RSM) were used to optimize experimental conditions for extraction of polyphenol and antioxidants from pomegranate peel using ethanol-water mixture as a food grade solvent.

Journal ArticleDOI
TL;DR: The results showed that this peptide has inhibitory effects on both Gram-negative and Gram-positive bacteria, and was elected for isolation of antioxidant peptides by reverse-phase high-performance liquid chromatography (RP-HPLC).

Journal ArticleDOI
TL;DR: In this paper, the antioxidant properties of millet hulls and hulls were studied for their total phenolic content (TPC), radical scavenging capacity, and antioxidant activity in a β-carotene/linoleate emulsion.