• Title, Summary, Keyword: DPPH

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An Antioxidant Capacity Assay Using a Polyvinyl Alcohol-Based DPPH Pellet

  • Ahn, Yeong-Hee;Yoo, Jong-Shin;Kim, Sung-Ho
    • Bulletin of the Korean Chemical Society
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    • v.31 no.9
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    • pp.2557-2560
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    • 2010
  • To assay for antioxidant capacity of natural products considered important in producing human health benefits, a practical and economical method using pellet techniques was developed. A standard visualizing reagent, 1,1diphenyl-2-picryl-hydrazyl (DPPH), was mixed with a water-miscible polyvinyl alcohol (PVA), serving as a solid phase support for the DPPH reagent. A DPPH pellet was prepared by dropping a small volume of the DPPH solution onto PET film, and drying in an oven. The PVA-based DPPH pellet was dissolved into water, in which the water-miscible PVA plays as a non-ionic surfactant to help the DPPH reagent to be dissolved into the solvent. Using the DPPH assay, the antioxidant capacity of water-soluble extracts of black soybean, barley, green tea, and green gram was examined. Among the natural products tested, green tea showed the highest antioxidant capacity. This PVA-based DPPH antioxidant assay can be further applied in the natural food, raw plant material, and health product inspection field.

Comparison of Oxidative Stability for the Thermally-oxidized Vegetable Oils using a DPPH Method (DPPH법에 의한 식용유지의 열산화 안정성 비교)

  • Lee, Jae-Min;Chang, Pahn-Shick;Lee, Jae-Hwan
    • Korean Journal of Food Science and Technology
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    • v.39 no.2
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    • pp.133-137
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    • 2007
  • The 2,2-diphenyl picrylhydrazyl (DPPH) method, which can be used to predict the oxidative stability of edible oils, was previously reported by our research group. Not only free radical scavenging antioxidants but also radicals from oxidized oils are capable of reacting with DPPH radicals, thereby reducing the absorbance of DPPH. In this study, the optimum sample size of edible oils for the DPPH method was determined, and the oxidation of the edible oils was monitored via DPPH, coupled with other conventional methods. The optimum sample size was determined as 1.5 g using soybean oil. Soybean, corn, virgin olive, and refined olive oils were thermally oxidized for 3 hr at $180^{\circ}C$ and analyzed via DPPH, conjugated dienoic acid (CDA) value, and p-anisidine value (p-AV) protocols. Soybean and corn oils were found to be more sensitive to thermal oxidation than virgin and refined olive oils, on the basis of the CDA value and p-AV measurements. The DPPH method can indicate the inherent radical scavenging activity of unoxidized samples, the time required for the depletion of antioxidants, and the rate of degradation of the antioxidants. The soybean and corn oils evidenced higher levels of free radical scavenging compounds, required more time for the consumption of inherent antioxidants, and also manifested steeper antioxidant degradation rates than olive oils, based on the results of DPPH analysis. The DPPH method, accompanied by other conventional methods, may prove useful in predicting the degree of oxidation of vegetable oils.

A Continuous Spectrophotometric Assay for NADPH-cytochrome P450 Reductase Activity Using 1,1-Diphenyl-2-Picrylhydrazyl

  • Yim, Sung-Kun;Yun, Su-Jung;Yun, Chul-Ho
    • BMB Reports
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    • v.37 no.5
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    • pp.629-633
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    • 2004
  • NADPH-cytochrome P450 reductase (CPR) transfers electrons from NADPH to cytochrome P450, and catalyzes the one-electron reduction of many drugs and foreign compounds. Various forms of spectrophotometric titration have been performed to investigate the electron-accepting properties of CPR, particularly, to examine its ability to reduce cytochrome c and ferricyanide. In this study, the reduction of 1,1-diphenyl-2-picrylhydrazyl (DPPH) by CPR was assessed as a means of monitoring CPR activity. The principle advantage of DPPH is that its reduction can be assayed directly in the reaction medium by a continuous spectrophotometry. Thus, electrons released from NADPH by CPR were transferred to DPPH, and DPPH reduction was then followed spectrophotometrically by measuring $A_{520}$ reduction. Optimal assay concentrations of DPPH, CPR, potassium phosphate buffer, and NADPH were first established. DPPH reduction activity was found to depend upon the strength of the buffer used, which was optimal at 100 mM potassium phosphate and pH 7.6. The extinction coefficient of DPPH was $4.09\;mM^{-1}\;cm^{-1}$. DPPH reduction followed classical Michaelis-Menten kinetics ($K_m\;=\;28\;{\mu}M$, $K_{cat}\;=\;1690\;min^{-1}$). This method uses readily available materials, and has the additional advantages of being rapid and inexpensive.

Effect of Heating on DPPH Radical Scavenging Activity of Meat Substitute

  • Song, Hyeun Sung;Bae, Jun Kyu;Park, Inshik
    • Preventive Nutrition and Food Science
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    • v.18 no.1
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    • pp.80-84
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    • 2013
  • This study was conducted to evaluate the increase of DPPH radical scavenging activity of meat substitute by heating. The meat substitute showed higher DPPH radical scavenging activity than those of other foods rich in protein such as beef, pork, chicken, and soybean curd. The DPPH radical scavenging activity of meat substitute was dependent upon concentration, heating temperature and heating time of meat substitute. The DPPH radical scavenging activity of meat substitute was enhanced with increasing heating temperature and time. The increase of DPPH radical scavenging activity was only applied to meat substitute without showing any activation in other foods rich in protein such as beef, pork, chicken, and soybean curd.

Identification of Antioxidative Constituents from Polygonum aviculare using LC-MS Coupled with DPPH Assay

  • Shin, Hyeji;Chung, Hayeon;Park, Byoungduck;Lee, Ki Yong
    • Natural Product Sciences
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    • v.22 no.1
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    • pp.64-69
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    • 2016
  • A method for simultaneously identifying antioxidative compounds was developed using time-based LC-MS coupled with DPPH assay regardless of the time consuming process. The methanolic extract of Polygonum aviculare (Polygonaceae) showed significant DPPH radical scavenging activity. Time-based DPPH assay for simultaneous identification of active compounds from the extracts of P. aviculare was used. Major peaks of ethyl acetate fraction of P. aviculare showed high DPPH radical scavenging activity. A simple phenolic compound (1) and six flavonoids (2-7) were isolated from the ethyl acetate fraction of P. aviculare by silica gel and sephadex LH-20 column chromatography. The structures of seven compounds were determined to be protocatechuic acid (1), catechin (2), myricitrin (3), epicatechin-3-O-gallate (4), avicularin (5), quercitrin (6), and juglanin (7) based on the analysis of the $^1H$-NMR, $^{13}C$-NMR and ESI-MS data. All compounds exhibited significant antioxidant activity on DPPH assay and active compounds were well correlated with predicted one.

Evaluation of DPPH Radical Scavenging Activity of Jeju Seaweeds Using High Throughput Screening (HTS) Technique (High Throughput Screening (HTS) 기법을 통한 제주 자생 해조류의 DPPH 라디칼 소거활성 평가)

  • Kim, Kil-Nam;Heo, Soo-Jin;Cha, Seon-Heui;Jeon, You-Jin
    • Journal of Marine Bioscience and Biotechnology
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    • v.1 no.3
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    • pp.170-177
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    • 2006
  • As a rapid and quick bioactive compound evaluation technique, in this study we utilized a automatic system of High Throughput Screening (HTS) to investigate DPPH radical scavenging efficacy of seaweeds, collected from Jeju Island in Korea. In this study, 6 species of green seaweeds, 18 species of brown seaweeds and 22 species of red seaweeds extracted with methanol at $20^{\circ}C$ and $70^{\circ}C$ were subjected to HTS. Of the green seaweeds tested, Enteromorpha compressa (20G6) of the green seaweeds showed DPPH radical scavenging activity of over 60%. On the other hand, the other green seaweeds showed poor DPPH radical scavenging activities (lees than 40%) at 1 mg/ml. Sargassum siliquastrum (20B17, 70B17), Dictyota dichotoma (70B1), Sargassum coreanum (70B16) and Ecklonia cava (70B26) among the brown seaweeds showed significantly high DPPH radical scavenging activity with 96%, 97%, 92%, 92%, 87%. Polysiphonia japonica (20R24), Schizymenia dubyi (20R17), Gelidium amansii (20R18) and Acrosorium flabellatum (20R23) among the red seaweeds showed remarkable DPPH radical scavenging activity of over 90%.

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The Total Phenolic Contents and DPPH Radical Scavenging Activities of Korean Potatoes according to Physical Characteristics and Cooking Methods (한국산 감자의 기관별, 품종별, 중량별, 분포별 및 조리 방법에 따른 총 페놀 함량과 DPPH 라디칼 소거능에 관한 연구)

  • Im, Hyo-Won;Suh, Bong-Soon
    • Journal of the East Asian Society of Dietary Life
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    • v.19 no.3
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    • pp.375-383
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    • 2009
  • This study was conducted to measure the total polyphenol contents and DPPH radical scavenging activities of different potato plants parts, varieties, and grades, and by distribution and different cooking conditions. The results were as follows. For the plant parts, total phenolic content and DPPH radical scavenging activity were highest in the flowers followed by leaves and stems, respectively. Among 5 potato varieties, 'Jasim' had the highest DPPH radical scavenging activity and the activity of its pulp was lower than that of its cortex(peel). Regardless of potato grade, the cortexes(peel) of samples had two-fold higher DPPH radical scavenging activity than pulp, and the Grade SS potato had the highest phenolic content. It was also found that the bud ends and stem ends had comparably larger amounts of phenolic compounds in horizontally cut potatoes. Finally, the descending order for DPPH radical scavenging activity, according to different cooking conditions, was as follows: gas oven range-baking, frying, microwave-heating, sauteing, boiling in 1% saline solution, steaming, and boiling in 3% saline solution.

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Optimum Condition for Pigment Production and Antioxidative Activity of the Products by Bacillus subtilis DC-2 with Response Surface Methodology (반응표면 분석에 의한 Bacillus subtilis DC-2의 색소생성 및 그 생성물의 항산화성에 대한 최적조건)

  • 최웅규;지원대;정현채;최동환;정영건
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.4
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    • pp.620-624
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    • 1997
  • The conditions for color intensity and electron donating ability to $\alpha$,$\alpha$-diphenyl-$\beta$- picryl-hydrazyl (DPPH) of Bacillus subtilis DC-2 were investigated. Temperature, pH and cultivation time were chosen as three factors, and the optimal conditions of color intensity and DPPH was determined with response surface methodology. Color intensity was affected by cultivation temperature(p<0.1). DPPH was influenced by cultivation temperature(p<0.05) and pH(p<0.1). But cultivation time was affected neither color in- tensity nor DPPH. Optimal conditions of color intensity with Bacillus subtilis DC-2 were appeared at cultivation temperature of 39.$25^{\circ}C$, pH 8.83 and cultivation time of 84.41hrs. Optimal conditions of DPPH with Bacillus subtilis DC-2 were revealed at cultivation temperature of 39.19$^{\circ}C$, pH 8.84 and cultivation time of 82.21hrs.

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Analysis of the Antioxidant Properties of 2,2-diphenyl-1 Picrylhydroazyl, Hydroxyl Radicals, and Nitric Oxide in Alaska Pollock Roe, with or without Natural Fermented Seasoned (알래스카 명란의 DPPH, OH, NO의 항산화 특성 분석)

  • Hwang, Ji-Young;Jang, Jong-Soo;Huh, Man Kyu
    • Journal of Life Science
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    • v.29 no.4
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    • pp.428-435
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    • 2019
  • Alaska pollock (Gadus chalcogrammus) is a marine fish species belonging to the family Gadidae. In this study, whether the Alaska Polloack Roe have antioxidant properties, 2,2-diphenyl-1 picrylhydroazyl (DPPH), hydroxyl radical (OH) reducing activity, and nitric oxide radical (NO) scavenging activity were evaluated in distilled water extract (DWE) and ethanol extract (ETE) of raw Alaska pollock roe, Gochujang Pollock roe, and fermented seasoned Pollock roe. The DPPH scavenging activity of the DWE with Gochujang Pollock roe was 71.9% at a concentration of 1.0 mg/ml and that of the ETE was 73.7% at the same concentration. The DPPH scavenging activity of the DWE with fermented seasoned Pollock roe was 78.0% at 1.0 mg/ml, whereas that of ETE was 78.4% at the same concentration. The $IC_{50}$ values of the DWE and ETE of raw Pollock roe for DPPH were $11.65{\mu}g/ml$ and $11.47{\mu}g/ml$, respectively. The OH scavenging activities of raw Pollock roe, Gochujang Pollock roe, and fermented seasoned Pollock roe ethanolic extracts at a concentration of 1.0 mg/ml were 70.9%, 79.0, and 80.6%, respectively. The $IC_{50}$ values of the DWE and EWE of raw Pollock roe for NO were $11.45{\mu}g/ml$ and $11.41{\mu}g/ml$, respectively. The DPPH, OH, and NO scavenging abilities in DWEs and ETEs of Gochujang and fermented seasoned Pollock roe were higher than those of instant (no Gochujang or season treatment) treatment Pollock roe. Both the Gochujang and fermented seasoned Pollock roes have natural radical scavenging ability and may be useful potential antioxidant food supplements.

한국 전통 한 그릇 음식(비빔밥) 및 그 재료들의 DPPH 수소공여능과 아질산염 소거능

  • 구성자;조연옥
    • Proceedings of the EASDL Conference
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    • pp.83-83
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    • 2003
  • Electron donating ability by DPPH and nitrite scavenge were measured in ethanol extracts from raw, simple cooked and seasoned materials of Bibimbab(mixed rice), Korean traditional one-dish meal. Ethanol extracts of raw frugrantedible wild aster showed the highest electron donating abilities(80.28%) by DPPH. When its seasoned materials were compared with raw and simple cooked materials, it showed the highest electron donating abilities by DPPH.(중략)

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