• Journal of Ginseng Research
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• 제14권2호
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• pp.191-199
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• 1990

It has been well known that extended exposure to reactive oxygens causes severe damage to susceptible biomolecules. In this study, the effects of flavonoids including trifolin and kaempferol from Ginseng leaves on singlet oxygen induced photohemolysis of erythrocytes and free radical scavenging activities were investigated. Each flavonoid aglycone (5-50$\mu$M) such as kaempferol, quercetin or baicalein exhibited a high protective effect against the photohemolysis. They protected the cells by scavenging $^1O_2$ and free radicals Although the free radical scavenging activities of the flavonoid glycosides were not much lower than those of their corresponding aglycones, their insolubility into lipid bilayers of membrane made them less effective in preventing the photohemolysis induced by $^1O_2$. The $^1O_2$ and free radical scavenging activities of flavonoids were estimated by the decomposition of the flavonoid by $^1O_2$ and the bleaching of free radicals by the flavonoid, respectively. The solubilization of the flavonoid into micells or erythrocytes was deduced from spectrophotometric and microscopic observations. The cooperation of L-ascorbic acid and a flavonoid, and a possible involvement of lipoxygenase or cyclooxygenase in the photohemolysis mechanism were discussed.

• ALGAE
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• 제18권4호
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• pp.341-347
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• 2003

The potential antioxidative activity of water-soluble enzymatic hydrolyzates from a kelp, Ecklonia cava was evaluated by free radical scavenging and lipid peroxidation assays. To prepare water-soluble hydrolyzates from E. cava the seaweed was enzymatically hydrolyzed by five carbohydrases (Viscozyme, Celluclast, AMG, Termamyl and Ultraflo) and five proteases (Protamex, Kojizyme, Neutrase, Flavourzyme and Alcalase). Among all the hydrolyzates, Celluclast hydrolyzate effectively scavenged free radicals released from DPPH (1,1-diphenyl-2- pricrylhydrazyl) and recorded around 73% scavenging activity at the concentration of 4 mg ${\cdot}ml^{-1}$. This hydrolyzate was thermally stable and DPPH radical scavenging activity remained 80% or higher at heating temperatures of 40 and 60$^{\circ}C$ up to 12 h and around 80% at 100$^{\circ}C$ up to 8 h. AMG and Ultraflo hydrolyzate inhibited the lipid peroxidation of fish oil as that of $\alpha$-tocopherol. These results suggested that an enzymatic extraction will be an effective way for the production of a potential antioxidant from seaweeds.

• Journal of Applied Biological Chemistry
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• 제50권3호
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• pp.115-119
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• 2007

To discover the sources with antioxidant and tyrosinase inhibitory activities in Korean traditional medicines, 10 extract of medicinal plants were screened for their potential to scavenge stable 1,1-diphenyl-2-picryhydrazyl (DPPH) free radical, inhibit hydroxyl radical (${\cdot}OH$), total phenolic content, and inhibition of tyrosinase. The potency of DPPH radical scavenging activity was shown in the extract of Ulmus davidiana var. japonica Nakai that has a greater effect with $IC_{50}$ values of $6.49{\pm}5.43{\mu}g/mL$, than BHA ($IC_{50}=20.99{\pm}0.74{\mu}g/mL$), L-ascorbic acid $(IC_{50}=20.59{\pm}1.06{\mu}g/mL),\;and\;{\alpha}-tocopherol\;(IC_{50}=25.55{\pm}0.26{\mu}g/mL)$ as a positive control. The ${\cdot}OH$ scavenging activities were observed in the plants tested. Acanthopanax senticosus, Cirsium setiders, U. davidiana exhibited scavenging activity of more than 60% at $500{\mu}g/mL$. The scavenging activity(%) of BHA and a-tocopherol were 64.32 and 55.87% at $500{\mu}g/mL$, respectively. The total phenolic content was determined, in order to assess its effect on the extract's antioxidant activity. The total phenoic content of $33.37{\pm}0.52mg/g$ was conformed by methanolic extract of U. davidiana. The U. davidiana and Morus bombycis exhibited tyrosinase inhibitory activity with a $34.28{\pm}1.32\;and\;75.57{\pm}1.10%$, respectively. In particular, M. bombycis has stronger tyrosinase inhibitory activity than albutin with $36.48{\pm}3.56%$ as a positive control. This work showed that the inhibitory abilities of Korean medicinal plants, such as U. davidiana and M. bombycis, on DPPH free radical, inhibit hydroxyl radical (${\cdot}OH$), and inhibition of tyrosinase and total phenolic content, can be useful in the prevention and treatment of free radical-relate disease. Investigations into further isolation of inhibitory principles of U. davidiana and M. bombycis are now in progress.

• 대한화장품학회지
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• 제39권3호
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• pp.195-203
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• 2013

본 연구에서는 금불초(Inula britannica) 종(種) 및 개화시기에 따른 금불초 추출물의 항산화 효능을 알아보았다. 이들 추출물의 free radical 소거활성을 살펴본 결과, 만개한 금불초 꽃(I. britannica var. chinensis) 추출물의 경우 500 ${\mu}g/mL$의 농도에서 79.89%의 free radical 소거활성을 보였으나, 금불초 유사종인 가는 금불초(I. britannica var. linariaefolia Regel), 가지 금불초(I. britannica var. ramosa) 및 버들 금불초(I. salicina var. asiatica)의 꽃 추출물의 경우 free radical 소거활성이 거의 나타나지 않았다. 또한 꽃이 만개하였을 경우 꽃 추출물 분획에서는 93.62%의 free radical 소거활성을 보였으며, 봉우리 추출물 분획은 43.28%, 낙화추출물 분획은 14.11%를 나타냈다. 금불초의 종 및 개화시기를 선정 후, 추출용매, 온도, 시간을 조절하여 최적의 추출조건을 확립하였다. 그 결과, $65^{\circ}C$ 에탄올 추출물에서 가장 높은 DPPH free radical 소거활성이 나타났으며, 시간에 따른 유의적 차이는 없는 것으로 나타났다. 만개한 금불초 꽃 추출물에 대하여 rose-bengal로 증감된 사람 적혈구의 광용혈 실험에서 세포보호효과를 측정한 결과, 5 ~ 50 ${\mu}g/mL$의 범위에서 농도 의존적으로 세포 보호 효과를 나타내었다. 특히 50 ${\mu}g/mL$의 농도에서 ${\tau}_{50}$이 116.1 min으로 비교물질인 (+)-${\alpha}$-tocopherol에 비해 1.58배 더 큰 세포 보호활성이 있음을 알 수 있었다. HPLC로 금불초 꽃 추출물을 분석한 결과 flavonoid의 일종인 quercetin이 다량 함유되어 있는 것을 확인하였다. 이상의 결과들은, $65^{\circ}C$ 에탄올로 추출한 만개한 금불초 꽃 추출물의 경우 다량의 quercetin을 함유하며, 그로 인하여 free radical 소거활성 및 ROS에 대항하여 세포막을 효과적으로 보호함으로써 태양 자외선에 노출된 피부를 보호하는 항산화제로서 작용할 수 있을 것으로 사료되며, 기능성 화장품 원료로서 응용 가능성이 있음을 시사한다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.271.1-271.1
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• 2003

In order to find the new hepatoprotective agents the preliminary screening of 12 prescriptions which have been used for the treatment of hepatic disease in Oriental traditional medicine has been carried out. Both DPPH free radical scavenging and hepatoprotective effect on tacrine-induced cytotoxicity in Hep G2 cells are performed. (omitted)

• 대한의생명과학회지
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• 제5권1호
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• pp.51-58
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• 1999

실험동물에 있어서 $CCl_4$에 의한 급성 간손상시 피부조직의 oxygen free radical 대사효소 활성 변동을 검토하기 위해 흰쥐에 $CCl_4$와 olive oil의 동량 혼합액을 체중 100g당 0.1 ml씩 복강으로 투여하여 처치하였다. $CCl_4$ 투여로 인한 혈청 alanine aminotransferase 및 xanthine oxidase (XO) 활성은 현저히 증가되었으며 체중당 간무게 (%)및 간조직의 malondialdehyde함량 역시 유의하게 증가되었다. 그리고 병리조직 검사에서도 $CCl_4$투여군에서 간조직의 괴사성 병변이 관찰되었다. 따라서 $CCl_4$를 투여한 실험동물이 급성 간손상 모델로 확인되었다. 이와 같은 간손상 실험동물의 피부조직중 oxygen free radical의 생성 효소인 XO 활성은 대조군과 별다른 차이를 볼 수 없었으나 oxygen free radical의 scavenging 효소인 superoxide dismutase, glutathione peroxidase 및 catalase 활성은 대조군에 비하여 유의하게 감소되었다. 또한 세포화학적 검사에서 cerrous perhydroxide과립이 간손상 실험동물의 피부조직에서 많이 나타났다. 이상 실험결과는 $CCl_4$에 의한 급성 간손상 유도 실험동물의 피부조직에 $H_2O$$_2$의 축적이 나타나는 현상을 시사해주고 있다.

• 대한한의학방제학회지
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• 제9권1호
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• pp.289-317
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• 2001

The purpose of this study was to reseach the effect of Daesihotang and its component groups on diabetes, free radical and antioxidative defense system in alloxan-induced diabetic rats. The experimental group was divided into three groups: Daesihotang (DS), Soyangyak (DS1), Yangmyungyak (DS2). The results were obtained as follows: The level of glucose, triglyceride, total cholesterol, creatinine in serum were considerablely reduced by Daesihotang. And the level of HDL cholesterol, albumin, total protein in serum were increased by Daesihotang significantly. And the level of BUN has some decreased, but with no significancy. In the study of Daesihotang on free radical scavenging effect in vitro, it has shown that Daesihotang and its components group have significant suppressing effect on peroxidation of linoleic acid on concentration. And in other experiments as scavenging effect of DPPH radical, inhibitory effect of superoxide in xanthine-xanthine oxidase system and inhibitory effect on lipid peroxidation reaction by hydroxy radical in $H_2O_2-Fe^{2+}$ system, Daesihatang have some activity, but with no significancy. In the study of Daesihotang on antioxidative defense system in vivo, the activity of GOT and GPT in serum were significantly increased; and the amounts of lipid peroxide in serum was reduced significantly but in liver no significancy. In hepatic catalase activity, Daesihotang has showed significant effect. In the level of hepatic glutathione, Daesihotang increased the amount of glutathione significantly. And in the activity of glutathione-s-transferase, Daesihotang has decreasing effect but has no significancy. These result suggest that Daesihotang has strong effect on diabetes and it is useful to prevent diabetes, but has less effect on peroxidative damage by free radical.

• Archives of Pharmacal Research
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• 제28권5호
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• pp.529-533
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• 2005

In the course of searching for hepatoprotective agents from natural products, six compounds were isolated from the MeOH extract of the leaves of Juglans sinensis, as guid ed by their DPPH free radical scavenging activity. The structures were determined as juglanoside B (1), quercetin 3-O-${\alpha}$-L-arabinofuranoside (avicularin, 2), quercetin 3-O-${\alpha}$-L-arabinopyranoside (guaijaverin,3), quercetin 3-O-${\alpha}$-L-rhamnopyranoside (quercitrin,4), (+)-catechin (5) and quercetin 3-O-${\beta}$- D-galactopyranoside (hyperin,6). Compounds 2-6 showed significant DPPH free radical scavenging effects. An evaluation for the hepatoprotective activity of the isolated compounds on drug-induced cytotoxicity was conducted, and compounds 1, 2, and 5 showed protective effects against nitrofurantoin-induced cytotoxicity, and compound 5 also exhibited a moderate protective effect on amiodarone-induced cytotoxicity in Hep G2 cells.

• 한국약용작물학회지
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• 제17권1호
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• pp.15-20
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• 2009

This study was carried out in order to determine the biological activities such as antioxidant activities in nine cultivars of Momordica charantia L. (Korea, China, Japan and Philippine native cultivars). Their antioxidant activities were measured using DPPH free radical scavenging, ABTS cation radical scavenging, and Nitrite scavenging ability. The highest total polyphenol content (16.82 ${\mu}g/m{\ell}$) measured in the native Korea cultivar, and this value was 4.0 ${\mu}g/m{\ell}$ higher than that of the 'Verde Beuhas' cultivar (12.82 ${\mu}g/m{\ell}$). The 'Peacock' cultivar had the highest total flavonoid amount which was 4.38 ${\mu}g/m{\ell}$. The free radical scavenging activity using DPPH method was the highest in the native China cultivar ($RC_{50}$ = 102.6 ${\mu}g/m{\ell}$). ABTS cation radical scavenging activity according to cultivars was significantly higher in 'Peacock'. Nitrite scavenging ability showed the most remarkable effect at the pH 1.2, exhibited to 81.5${\sim}$86.9% by addition of ethanol extract 1${\mu}g/m{\ell}$ from Momordica charantia L. These results suggest that Momordica charantia L. had the potent biological activities, and that their activities exhibited differently depending on cultivars.

• 동의생리병리학회지
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• 제19권5호
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• pp.1349-1355
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• 2005

The steamed root of Rehmannia glutinosa has been used for treatment of inner ear diseases, such as tinnitus and hearing loss in traditional Oriental Medicine. In the present study, we investigated the effect of ethanol extract of steamed root R. glutinosa (SRG) on cisplatin cytotoxicity of HEI-OC1 auditory cells. In addition, to investigate the mechanism of SRG on cisplatin cytotoxicity, the effects of SRG on lipid peroxidation as well as scavenging activities against various free radicals were measured in cisplatin-treated cells. Treatment of SRG protected cells from cisplatin and reduced lipid peroxidation in a dose-dependent manner. Furthermore, SRG demonstrated significant scavenging activity against various free radicals, including superoxide radical, hydroxyl radical, hydrogen peroxide, and DPPH radical. These results indicate that SRG protects cisplatin-induced damages of HEI-OC1 cells through inhibition of lipid peroxidation and augmenting scavenging activities against free radials.