• 제목, 요약, 키워드: 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.

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

  • 이재민;장판식;이재환
    • 한국식품과학회지
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    • v.39 no.2
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    • pp.133-137
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    • 2007
  • 유지의 산화안정도 측정을 위해 개발된 DPPH법의 최적화를 위해 시료의 양에 따른 유지의 산화변화를 분석하였고, 결정도니 조건을 사용하여 시중에서 튀김유로 사용되는 4종류 식용유지의 열산화안정성을 측정하였다. CDA와 p-AV는 산화반응이 진행될수록 증가하였으며 시료간의 상대적인 산화안정성 차이를 확인할 수 있었다. 반면에 DPPH법은 유지의 산화라디칼과의 반응성을 이용하며 흡광도의 증가와 감소를 반복하는 경향을 나타냈고 이로부터 유지산화라디칼의 변화를 측정 할 수 있었다. 또한 유지의 초기 전자 혹은 수소공여능을 확인할 수 있었고, DPPH 흡광도 증가를 통해 산화방지물질의 소진속도 및 산화라디칼의 생성속도를 계산할 수 있었으며, 산화방지물질의 소진시점을 결정할 수 있었다. 따라서 DPPH법을 기존의 산화도 측정방법과 병용한다면 유지의 산화도는 물론 산화반응 단계를 측정 할 수 있고, 산화안정성을 예측하는데 도움이 될 것으로 기대된다.

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.

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

  • 김길남;허수진;차선희;전유진
    • 한국해양바이오학회지
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    • v.1 no.3
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    • pp.170-177
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    • 2006
  • 본 연구는 제주산 해조류의 생리활성을 대량검색하기 위해 HTS 기법을 이용한 실험과정의 제어 및 관리를 위한 자동화 시스템을 구축하고자 DPPH 라디칼을 이용하여 HTS를 이용한 자동화 시스템을 구축하고 제주산 해조류의 DPPH 라디칼 소거활성을 대량 검색하고자 하였다. 그 결과 HTS를 위한 효율적인 검색방법을 개발하였고 DPPH 라디칼 소거활성이 높은 해조류를 검색하게 되었다. 녹조류의 경우 납작파래 (20G6)의 $20^{\circ}C$ 추출물(1 mg/ml)에서 약 60%이 DPPH 라디칼 소거활성을 보였을 뿐 나머지 해조류에서는 40% 미만이 낮은 활성만을 보였다. 갈조류의 경우 꽈배기 모자반 (20B17), (70B17), 참그물바탕말 (70B1), 큰잎모자반 (70B16)과 감태 (70B26)에서 DPPH 라디칼 소거활성이 우수하였다. 홍조류 중에서는 왜떨기나무붉은실 (20R24)에서 가장 우수한 DPPH 라디칼 소거활성을 나타내었고 갈래잎 (20R17), 굵은참우뭇가사리 (20R18), 부채분홍잎 (20R23) 또한 높은 소거활성을 보였다. 따라서 우수한 효과를 나타내었던 해조류를 대상으로 용매분획 및 활성물질의 분리, 정제를 통해 해조류 유래의 기능성 신소재를 개발한다면, 해조류의 고부가가치화 및 HTS기술의 보편화에 큰 영향을 미칠 것으로 판단된다.

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

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

  • 최웅규;지원대;정현채;최동환;정영건
    • 한국식품영양과학회지
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    • v.26 no.4
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    • pp.620-624
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    • 1997
  • 온도, pH, 배양시간을 세가지 인자로 하고 반응표면 분석을 통하여 Bacillus subtilis DC-2균에 의한 색소 생성 및 DPPH($\alpha$,$\alpha$-diphenyl-$\beta$-picryl-hydrazyl)에 의한 전자공여성의 최적 조건을 조사하였다. 색소생성능에는 배양온도가 10% 유의수준에서 영향을 미치는 것으로 나타났으며, DPPH에 의한 전자공여성의 경우 배양온도가 5% 유의수준, pH가 10% 유의수준에서 영향을 미치며, 배양시간은 10% 유의수준에서 영향을 미치지 않는 것으로 나타났다. Bacillus subtilis DC-2의 색소생성 최적 조건은 배양온도 39.$25^{\circ}C$, pH 8.83 및 84.41 시간으로 나타났으며 DPPH에 의한 전자공여성은 배양 온도 39.19$^{\circ}C$, pH 8.84 및 82.21시간에서 가장 높은 것으로 나타났다.

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알래스카 명란의 DPPH, OH, NO의 항산화 특성 분석 (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)

  • 황지영;장종수;허만규
    • 생명과학회지
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    • v.29 no.4
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    • pp.428-435
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    • 2019
  • 알래스카 산 대구(Gadus chalcogrammus)는 대구과(family Gadidae)의 해산어종이다. 알래스카 명란 원료, 고추장 명란, 발효 명란을 증류수와 에탄올로 추출하여 2, 2- diphenyl - 1- picrylhydroazyl (DPPH), 하이드록시 라디칼(OH), 산화질소(NO)의 항산화 소거능을 평가하였다. 철 이온 환원력(FRAP)을 조사하였다. ABTS+ 소거능은 Brand-Williams 등의 방법에 따랐다. 고추장 명란의 증류수 추출물의 DPPH 소거능은 1.0 mg/ml 농도에서 71.9%였으며 에탄올 추출물에서 소거능은 73.7%였다. 발효 명란의 증류수 추출물의 DPPH 소거능은 1.0 mg/ml 농도에서 78.0%였고 에탄올 추출물에서 소거능은 78.4%였다. 명란 원료의 증류수 추출물과 에탄올 추출물의 DPPH에 대한 최소 저해 농도 값($IC_{50}$)은 각각 11.65 ug/ml과 11.47 ug/ml이었다. 명란 원료, 고추장 명란, 발효 명란의 에탄올 추출물의 OH 소거능은 1.0 mg/ml 농도에서 70.9%, 79.0, and 80.6%였다. 명란 원료의 증류수 추출물과 에탄올 추출물의 NO의 최소 저해 농도 값은 11.45 ug/ml과 11.41 ug/ml였다. 본 연구 결과, 고추장 명란과 발효명란은 원료 명란 보다 높은 DPPH, OH, NO 소거능을 나타내었다. 고추장 명란과 발효 명란은 자연 라디칼 소거능이 있어 식품으로써 항산화 보충제가 될 수 있을 것이다.

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

  • 구성자;조연옥
    • 동아시아식생활학회:학술대회논문집
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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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