• Title, Summary, Keyword: radical scavenger

Search Result 266, Processing Time 0.042 seconds

Free Radical Scavenger로서의 Plant Phenolics의 특성과 항산화 활성

  • 이정수;최홍식
    • Journal of Life Science
    • /
    • v.4 no.1
    • /
    • pp.11-18
    • /
    • 1994
  • Plant phenolics은 식물 생체에 널리 분포되어 있으므로 매일 일정량이 식품으로 섭취되어지고 있으며, 이 물질들은 식품 외에도 일부 향신료 및 의약용으로 이용되어지고 있다. 본 논문에서는 plant phenolics이 free radical scavenger로서의 주요 작용을 포함한 항산화 메카니즘과 기타 항산화 특성, 그리고 plant phenolic계 free radical scavenger 물질인 flavonoids와 hydroxycinnamic acids 및 hydroxycinnamic acid derivatives의 항산화 활성과 구조 간의 관계에 초점을 두어 고찰하였다. 또한 주요 식물별 plant phenolics 물질의 특성과 항산화 활성에 대하여서도 검토하였다.

  • PDF

Acetycholinesterase Inhibiting Effect and Free Radical Scavenging Effect of Soybean(Glycine max) and Yak-Kong(Rhynchosia nolubilis) (대두와 약콩의 Acetylcholinesterase 활성 억제효과와 항산화 효과)

  • 강순아;한진아
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.14 no.1
    • /
    • pp.64-69
    • /
    • 2004
  • The deficiency of the neurotransmitter acetylcholine(ACh) is responsible for the initiation of Alzheimer's disease. In addition, there is a simple evidence that oxidative stress significantly increases in persons with Parkinson's disease compared to age-matched healthy persons. Therefore, the objective of the study was to investigate the neurodegeneration inhibitory effect of soybean(Glycine Max) and Yak-Kong(Rhynchosia Nolubilis) by measuring the degree of inhibiting Acetylcholinesterase (AChE) catabolizing the ACh and the free radical scavenger effect in vitro. AChE was measured by the minor modified Ellman assay. Free radical scavenging activity was measured using l-diphenyl-2-picrylhydrazyl (DPPH). First, the MeOH extracts of Soybean and Yak-Kong showed the AChE inhibiting activity of 62.0$\pm$2.43% and 65.0$\pm$3.29% at the 5 mg/$m\ell$ concentration. The 50% inhibitory concentration ($IC_{50}$/) of AChE was 1.96 and 1.31 mg/$m\ell$ in the MeOH extracts of soybean and Yak-Kong. Second, the MeOH extracts of soybean and Yak-Kong showed the free radical scavenger activity of 23.1$\pm$4.26% and 80.7$\pm$4.61% at the 5 mg/$m\ell$. IC50 of free radical scavenger activity in Soybean and Yak-Kong was 13.00 and 1.41 mg/$m\ell$ in MeOH extracts and was 5.95 and 2.74 mg/$m\ell$ in hot-water extracts, respectively. In this study, the extracts of Soybean and Yak-Kong showed powerful effects in the AChE inhibition and free radical scavenging. The extracts of Soybean and Yak-Kong were expected to prevent the many neurodegenerative diseases.

  • PDF

Syntheses of Resveratrol and its Hydroxylated Derivatives as Radical Scavenger and Tyrosinase Inhibitor

  • Lee, Hyun-Suck;Lee, Byung-Won;Kim, Mi-Ran;Jun, Jong-Gab
    • Bulletin of the Korean Chemical Society
    • /
    • v.31 no.4
    • /
    • pp.971-975
    • /
    • 2010
  • Eight hydroxylated stilbene derivatives including resveratrol, desoxyrhapontigenin and piceatannol as potential radical scavenger and tyrosinase inhibitor are synthesized using optimized Wittig-Horner reaction for excellent trans-selectivity in good yields. Antioxidant activity was tested against ABTS radical and tyrosinase inhibitory activity was performed with L-tyrosine as the substrate based on previous procedure with some modification. In general, catecholic stilbenes showed stronger activity against ABTS radical and resorcinolic moiety showed stronger tyrosinase inhibitory activity. Synthetic piceatannol which containing both catecholic and resorcinolic moieties showed the strongest activity in both as ABTS radical scavenger and tyrosinase inhibitor with $IC_{50}$ values of 4.1 and $8.6\;{\mu}M$, respectively.

Purification and Physicochemical Properties of Superoxide Anion Radical Scavenger from Capsella bursa-pastoris (냉이(Capsella bursa-pastoris)로부터 Superoxide Anion Radical 소거물질의 정제 및 이화학적 성질)

  • Kwak, Jae-Hyock;Kweon, Mee-Hyang;Ra, Kyung-Soo;Sung, Ha-Chin;Yang, Han-Chul
    • Korean Journal of Food Science and Technology
    • /
    • v.28 no.1
    • /
    • pp.184-189
    • /
    • 1996
  • A scavenger of superoxide anion radical which causes oxygen toxicity was isolated from Capsella bursa-pastoris, and its physicochemical properties were investigated. The scavenger was isolated and purified by solvent fractionation and liquid column chromatographies (Amberlite XAD-2, Sephadex LH-20, Bio gel P-2, ODS (silica gel with 100% octadecyl silanization)). An active compound of 0.25 g was finally isolated by Fast Protein Liquid chromatography (FPLC) from 100 g ethanol extract of Capsella bursa-pastoris. A 50% decrease of superoxide anion radical was obtained with the scavenger compound of 0.58 g. The compound was assumed to be a phenolic glycoside from its physicochemical properties.

  • PDF

The estimation of Hydroxyl radical generation rate in Ozonation (오존산화공정에서 수산화라디칼(OH.)의 생성속도 측정)

  • 권충일;공성호;배성렬
    • Journal of Soil and Groundwater Environment
    • /
    • v.6 no.1
    • /
    • pp.3-12
    • /
    • 2001
  • During ozonation process, the hydroxyl radical generation rates were measured under different experimental conditions (ozone feed rate, nitrobenzene concentration, hydroxyl radical scavenger, pH, HO$_2$O$_2$/O$_3$ etc.) Nitrobenzene could be decomposed by hydroxyl radical rather than ozone only and nitrobenzene decomposition rate was expressed with functions of ozone and nitrobenzene concentration. The rate was decreased as the hydroxyl radical scavenger concentration was increased, and all results were followed pseudo first-order reaction. Using a competitive method, hydroxyl radical generation rate was measured with probe compound and scavenger. It was proportional to ozone concentration, and 0.24mo1 of hydroxyl radical was produced with 1mol of ozone. Under different pH conditions, hydroxyl radical generation rates were measured (pH 10.2 (0.91Ms$^{-1}$ ) > pH 7.3 (0.72Ms$^{-1}$ ) > pH 5.6 (0.67Ms$^{-1}$ ) > pH 3.4 (0.63Ms$^{-1}$ )) showing higher generation rate at high pH values. Addition of hydrogen peroxide promoted the generation rate of hydroxyl radical. Considering the results of pH experiments and addition of hydrogen peroxide experiments, the hydroxyl radical generation rate was 1.6 times higher in hydrogen peroxide solution than in high pH solution, indicating addition of hydrogen peroxide is better promoter to produce the hydroxyl radical in ozonation. These results could be applied to AOPs to remediate the contaminated wastewater and groundwater.

  • PDF

Recent Research Trend on Free Radical Scavenger and Metallothioneins on Cadmium (Cadmium에 대한 Metallothionein 및 Free Radical Scavenger에 관한 최근의 연구 동향)

  • 김영숙;유대식
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.11 no.1
    • /
    • pp.1-10
    • /
    • 2001
  • Since the Industrial Revolution, people have enjoyed an abundant life, owing to the technological innovations of science. However, because of changes in the environment or polution to the environment, it has brought on many chronic diseases. Especially, even though it may be a small amount, if cadmium gets into a human body, because its biological half life is long, it fatally causes a kidney disease and damage to human organisms. It was reported that Metallothioneins(MT), a substance that is closely related with a free radical that comes from environmental pollution and the course of which cadmium, which causes chronic addition in the body, is formed, along with harmful metals, make the toxicity reduce. MT compound led into the body by cadmium indirectly functions as an antioxidation, supplied adequate amount of vitamin E, and suppresses the accumulation of cadmium in heart, liver and blood. Cadmium content found in Korean soil according to the test conducted from 1992 to 1996 was 0.02~0.03mg/kg in cereals, pulses, and potatoes. Free radical scavenger, finding solution for metal substance that comes from environmental pollution from food and natural substances implicates a better future for the study of food science.

  • PDF

Decrease of Membrane Degradation in PEMFC by Fucoidan (후코이단에 의한 PEMFC 고분자막의 열화 감소)

  • Oh, Sohyung;Kak, Ahyeon;Oh, Sungjun;Lee, Daewoong;Na, Il-Chai;Park, Kwonpil
    • Korean Chemical Engineering Research
    • /
    • v.58 no.1
    • /
    • pp.59-63
    • /
    • 2020
  • Radical scavenger is used to improve the durability of PEMFC polymer membrane. In this study, we investigated whether fucoidan extracted from seaweed as a radical scavenger prevents electrochemical degradation through Fenton and OCV Holding experiments. Fucoidan has an antioxidant effect, protecting the polymer membrane from hydrogen peroxide and oxygen radicals, reducing the degradation rate to 1/10. Fucoidan has been shown to be more effective than MnO2, which is used as a radical scavenger. In the PEMFC cell, the accelerated durability evaluation method (OCV Holding) showed that fucoidan reduced the hydrogen permeability of the polymer membrane by 12% and enhanced the performance by 29.1% compared to without radical scavenger. And fucoidan was found to be more effective in the cathode side ionomer than the anode side.

An Improved method in Screening of Superoxide and Hydroxyl Radical Scavenging Activities of Plant Medicinal Extracts (생약 추출물에 의한 superoxide와 hydroxyl 라디칼 소거능 검색 방법의 개선)

  • Lee, Ho-Sub;Kang, Dae-Gill
    • Korean Journal of Pharmacognosy
    • /
    • v.32 no.3
    • /
    • pp.253-256
    • /
    • 2001
  • The present study was designed for the improvement of routine measurement of superoxide and hydroxyl radical scavenging activities utilized by a microplate reader. Superoxide radical scavenging activity by the ascorbic acid, which is a well-known superoxide scavenger, was determined in a dose-dependent manner. Hydroxyl radical scavenging activity by the thiourea, which is a well-known hydroxyl radical scavenger, was also well detected in a dose-dependent manner. Our results suggest that the use of microplate reader to assay the superoxide and hydroxyl radical scavenging activities improves the accuracy of data and enables the use of much smaller amounts of samples and/or reagents, with much simpler experimental procedure. Therefore, These methods appear to be suitable for screening of superoxide and hydroxyl radical scavenging activities in both the plant medicinal extracts and the isolated compounds.

  • PDF

Effect of Silkworm Powder on Oxygen radicals and Their Scavenger Enzymes in Brain membranes of SD Rats (뇌조직의 활성산소 및 그 제거효소에 미치는 누에분말의 영향)

  • 최진호;김대익;박수현;김동우;김정민;이희삼;류강선
    • Journal of Sericultural and Entomological Science
    • /
    • v.42 no.2
    • /
    • pp.93-98
    • /
    • 2000
  • This study was designed to investigate the effect of silkworm powder on oxygen radicals and their scavenger enzymes in brain membrances of SD rats. Hydroxyl radical (OH) levels resulted in a considerable decreases in brain mitochondria fraction. Superoxide radical (O$_2$) levels were a slightly decreased in brain cytosol fraction. Lipid peroxide (LPO) and Oxidized protein (OP) levels were significantly decreased in brain mitochondria and microsomes fraction. Mn-superoxide dismutase (SOD) activity was remarkably increased in the mitochondria fraction. Cu and Zn-SOD activities were effectively increased in brain cytosol fraction. GSHPx activity was considerably increased in brain cytosol fraction. These results suggest that anti-aging effect of silkworm plays an effective role in attenuating an oxidative stress and increasing a scravenger enzyme activity in brain membranes.

  • PDF

Variations in radiochemical purity according to temperature of storage and radical scavenger

  • Kim, Deok Ju;Kim, Min Soo;Kim, Jin Seok;Bae, Yeon Gyu;Sun, Chan Young;Choi, Seung Jae;Lee, Sang-Yoon
    • Journal of Radiopharmaceuticals and Molecular Probes
    • /
    • v.2 no.2
    • /
    • pp.132-136
    • /
    • 2016
  • Radiolysis is the process of decreasing in Radio-Chemical Purity (RCP) of [$^{18}F$]FDG by direct effect and indirect effect of self Radio-activity. The objective of our study was to figure out the ideal conditions which minimize damages of quality of [$^{18}F$]FDG using radical scavenger and controlling temperature of storage.