• International Journal of Oral Biology
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• 제30권3호
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• pp.77-84
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• 2005

EGCG[(-)-epigallocatechin gallate], is a major component of green tea has been considered as a major antioxidant constituent. It has been considered as potential chemopreventive and chemotherapeutic agents. However, very little is known about the cellular actions by which EGCG mediates its therapeutic effects. Various aspects of antioxidant activity of EGCG were evaluated in this study. EGCG itself did not show significant cytotoxicity. Significant 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was observed in all ranges of concentration ($0.8-100{\mu}g/ml$) used in this study. Protective effect of EGCG against hydrogen peroxide induced cell death was observed. Relatively high lipid peroxidation inhibitory activity were detected ($IC_{50}$ was about $20{\mu}g/ml$). EGCG also dose-dependently enhanced the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in V79-4 cells. In concentrations of $100{\mu}g/ml$ of EGCG, activities of SOD, CAT and GPX were measured as 36.9 U/mg of protein, 22.9 U/mg of protein and 17.8 U/mg of protein, respectively. When these values were compared with those of the control groups (24.9 U/mg of protein, 14.9 U/mg of protein and 11.7 U/mg of protein), the relative increases were calculated as 48, 54 and 52%, respectively. Taken together, our findings suggest that EGCG can act as an antioxidant by scavenging radicals and enhancing antioxidant enzyme activities.

• 한국식품영양학회지
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• 제34권1호
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• pp.1-14
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• 2021

This study evaluated the antioxidant activity and quality characteristics of rice cookie with added butterbur powder in a ratio of 0, 5, 10, 15, and 20% to confirm the possibility of butterbur as a functional food. The moisture content, spread factor, leavening rate, and hardness of rice cookies increased with an increase in the amount of butterbur powder; whereas a decrease in the pH and baking loss rate was observed. The L and b values decreased as the amount of butterbur powder increased, but the value was the lowest when 5% of butterbur powder was added. The sensory liking score showed the highest preference for 10% butterbur powder regarding appearance, flavor, taste, texture, and overall preference. In the principal component analysis (PCA), the addition of 10% butterbur powder positively affected the measure of food acceptance in terms of organoleptic properties of butterbur. Besides, as the amount of added butterbur powder increased, the antioxidant activity of rice cookies increased. Based on these results, it appears that the addition of butterbur powder to rice cookies in a 10% ratio can produce rice cookies with excellent antioxidant activity, overall quality, and high preference.

• 한국식생활문화학회지
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• 제36권2호
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• pp.210-217
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• 2021

This study evaluated the biological activity and cytoprotective effect of guava (Psidium guajava L.) branch against oxidative stress. The contents of vitamin C, beta-carotene, total carotenoids, quercetin and catechin determined were 26.783, 43.676, 65.083, 58.245, and 8.309 mg/100 g, respectively. To measure antioxidant activity, the guava branch was extracted using various concentrations of ethanol (60, 80, or 100%) and water. The highest content of polyphenols (0.245 mg gallic acid equivalent/mg residue) and flavonoids (0.128 mg cathechin equivalent/mg residue) was found in the 100% ethanol extract of the branch (E100). Moreover, E100 also possessed the highest radical scavenging activities and showed the highest inhibition rate of α-glucosidase (77.692%). E100 was the most effective extract to impart cytoprotectant activity against oxidative stress in HepG2 cells. Taken together, our results determine the promising antioxidant activity of guava branch, and indicate the potential to be applied as a natural antioxidant.

• 한국식품과학회지
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• 제17권2호
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• pp.55-59
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• 1985

생강으로부터 분리한 gingerol의 산화방지 효과에 대하여 시험하였다. 생강의 에탄올 추출물로부터 핵산-에테르 혼합용매를 이용하여 crude gingerol을 얻어 TLC에 의하여 gingerol을 분리.정제하였다. 분리한 gingerol은 발색반응, 산탈수반응, UV, IR 및 NMR 스펙트로메트리등을 거처 6- 및 10-gingerol임을 동정하였다. Gingerol은 리노레산-${\beta}$-카로틴-물의 메멀죤에 0.02%(w/v)농도로 첨가되었을 때 대조구에서보다 ${\beta}$-카로틴을 크게 안정화시켰다. 그러나 BHA 및 BHT보다는 그 효과가 약간 낮았다.

• 한국식품과학회지
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• 제53권1호
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• pp.85-91
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• 2021

The physicochemical properties of deodeok (Codonopsis lanceolate) was investigated in relation to the different steaming time and cycles of steaming and drying (S/D). Additionally, the quality characteristics of Makgeolli with different amount (0-0.45%) of steaming and drying deodeok (SD) were measured comparison to non-steaming and drying deodeok (NSD). L⁎ values of deodeok tended to decrease as the number of S/D cycles and steaming times increased, while BI showed the opposite trend for L⁎ values. Reducing sugar increased significantly from 1 to 3 S/D cycles and decreased thereafter (p<0.05). Also, processed with steaming for 4 h and 5 S/D cycles had the highest antioxidant properties. Principal component analysis (PCA) revealed that the S/D process notably influenced the properties of deodeok. Quality characteristics of Makgeolli showed that 0.45% SD resulted in higher antioxidant properties than control or NSD.

• International Journal of Industrial Entomology and Biomaterials
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• 제40권1호
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• pp.16-21
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• 2020

Humans use insects as food and traditional medicine for many years. Hemolymph is the circulating fluid of insects and is a key component of their immune system. However, limited information is available regarding hemolymph identification, development, and differentiation, as well as the related cellular immune responses. In a previous study, hemolymph extracts prepared from Bombyx mori larvae were found to exert anti-inflammatory effects. In this study, we aimed to identify and compare the antioxidant activity of immune-challenged and unchallenged B. mori hemolymph extracts in vitro. For this purpose, human epithelial Caco-2 cells were first exposed to oxidative stress and then treated with various concentrations and incubation times of either immune-challenged or unchallenged B. mori hemolymph extracts. Next, we determined the effect of treatment on the relative expression of GPX-1, SOD-1, and SOD-2 antioxidant marker genes. We found that the expression rates of the three marker genes were markedly higher at a immune-challenged hemolymph extract concentration of 80 ppm compared to those at other concentrations, and the antioxidant effects were enhanced after treatment for 48 hr. Thus, B. mori hemolymph extracts showed antioxidant activity within the limited time and dose. Especially, the immune-challenged B. mori hemolymph extracts showed higher the antioxidant activities than unchallenged one. The activity of silkworm hemolymph extracts could facilitate the development of new types of functional foods, feed additives, and biomaterials with antioxidant properties.

• 한국식품과학회지
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• 제29권3호
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• pp.595-600
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• 1997

양파껍질중에 존재하는 항산화물질을 여러 용매로 분획하여 그 항산화효과를 비교하고, butanol fraction의 TLC에 의한 재분획 및 총페놀함량, 수소공여능 및 UV spectral 분석을 행하였다. 메타놀추출물의 항산화 효과는 첨가농도가 증가함에 따라 증가되었다. 메타놀추출물의 용매 분획물의 항산화효과는 buthanol> ethyl acetate> ethyl ether>water fraction의 순으로 나타났다. 이들의 항산화효과는 총페놀함량 및 수소공여능과 밀접한 관계를 보였다. TLC에 의한 butanol fraction의 재분획 결과 Rf치 0.20, 0.33, 0.49, 0.60 및 0.94을 나타내는 형광띠를 나타내었다. Rf치 0.94의 형광 band는 다른 형광 band에 비해 현저히 강한 것으로 보여 주었으며 flavonol의 존재를 나타내는 에서 나타나는 255 nm와 317 nm에서 강한 흡수가 보였다. Spectral analyses 결과 양파껍질 중에 함유되어 있는 주요 항산화성 물질은 quercetin aglycone (3,3',4',5,7-pentahydroxyflavone)인 것으로 확인되었다.

• 동아시아식생활학회지
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• 제25권6호
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• pp.1018-1028
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• 2015

This study was performed to investigate the effects of Gastrodia elata extract on the quality characteristics of glutinous rice porridge Jochung saccharide by barley malt. Glutinous rice porridge Jochung contatining 0%, 5%, 10%, 15%, 20% of Gastrodia elata extract were produced. Soluble solid contents and pH increased as content of Gastrodia elata extract increased. Free acidity contents were 24.87 meq/kg (control) and 25.67~42.03 meq/kg (GR2~GR5) (p<0.001 among samples). There was significant total phenolics and TEAC obtained for antioxidant activity of Gastrodia elata extract Jochung samples. Increased the ratio of Gastrodia elata extract in Jochung tended to decrease the color value. Results show Jochung containg less than 15% Gastrodia elata extract resulted in the highest scores for quality characteristics and sensory evaluation. Correlations between antioxidant activity and parameters were found to be statistically significant.

• Journal of the Korean Wood Science and Technology
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• 제48권6호
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• pp.878-887
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• 2020

A neutral extract (NE), that is soluble in cold water and has excellent antioxidant activity, from Pinus radiata pine bark was prepared by sodium bicarbonate treatment, and its chemical characteristics were investigated. NE was prepared by treating P. radiata bark with 0.8% NaHCO₃ aqueous solution with a 5 : 1 liquor-to-bark ratio at boiling temperature for 1 h, resulting in 44% yield and final pH of 6.66. The yield of NE was 11% higher than that of the hot water extract (HWE) due to the increase in the solubility of polyphenols, the main component in the bark, by NaHCO₃ treatment. NE was characterized through FT-IR, NMR, and MALDI TOF MS analyses. The results indicated that NE is mostly composed of proanthocyanidins (PAs) consisting of procyanidin (PC) units. The acetylated neutral extract (Ac-NE) had weight average molecular weight (${\bar{M}}w$) of 5,300 Da. The Ac-NE had wide molecular weight distribution and its polydispersity (${\bar{M}}w/{\bar{M}}n$) was 6 times higher than that of pure PA. The antioxidant activity of NE was determined by 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and showed that NE had comparable antioxidant activity with pure PA.

• BMB Reports
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• 제38권5호
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• pp.563-570
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• 2005

Tamoxifen citrate (TAM), is widely used for treatment of breast cancer. It showed a degree of hepatic carcinogenesis. The purpose of this study was to elucidate the antioxidant capacity of green tea (Camellia sinensis) extract (GTE) against TAM-induced liver injury. A model of liver injury in female rats was done by intraperitoneal injection of TAM in a dose of $45\;mg\;Kg^{-1}\;day^{-1}$, i.p. for 7 successive days. GTE in the concentration of 1.5%, was orally administered 4 days prior and 14 days after TAM-intoxication as a sole source of drinking water. The antioxidant flavonoid; epicatechin (a component of green tea) was not detectable in liver and blood of rats in either normal control or TAM-intoxicated group, however, TAM intoxication resulted in a significant decrease of its level in liver homogenate of tamoxifen-intoxicated rats. The model of TAM-intoxication elicited significant declines in the antioxidant enzymes (glutathione-S-transferase,glutathione peroxidase, superoxide dismutase and catalase) and reduced glutathione concomitant with significant elevations transaminase) levels. The oral administration of 1.5% GTE to TAM-intoxicated rats, produced significant increments in the antioxidant enzymes and reduced glutathione concomitant with significant decrements in TBARS and liver transaminases levels. The data obtained from this study speculated that 1.5% GTE has the capacity to scavenge free radical and can protect against oxidative stress induced by TAM intoxication. Supplementation of GTE could be useful in alleviating tamoxifen-induced liver injury in rats.