• 한국환경성돌연변이발암원학회지
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• 제26권4호
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• pp.119-124
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• 2006

There are $10{\sim}30%$ polyphenol and $2{\sim}4%$ caffeine in green tea. Caffeine is a kind of alkaloid containing nitrogen which cause stimulation, impatience, headache, insomnia, low birth weight infant. Because of these negative effect, decaffeined beverage came out and decaffeined coffee already have a big market since 1970s. Having proving the physiologic functions of green tea, high consumption of coffee is shifting to green tea. Because of the carcinogenic effect of the organic solvents, decaffeine processing with supercritical carbon dioxide has industrialized and have an advantage in environment-friendly and minimized flavor loss. Decaffeined green tea using supercritical carbon dioxide is considered to be safe but there are not enough study. We investigated the chromosome aberration test with mammalian cell line, CHL. When the cells were treated with 5000, 2000, 1000 ${\mu}g/ml$ and compared with the negative controls, there were no significant(P>0.05) increased chromosome aberration. Same results was observed when adding S9 mixture or not. As a result, water extract of decaffeined green tea using supercritical carbon dioxide does not induce chromosome aberration.

• 한국약용작물학회지
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• 제18권4호
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• pp.224-230
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• 2010

This study was conducted to investigate anti-oxidative and inflammatory inhibition effects of green tea and dietary fiber mixture on liver of high fat diet-induced obese rats. 21 male rats were divided into 3 dietary groups and control group (A), high fat diet-induced group (B), and high fat (HF) diet-induced + EQ diet-$S^{(R)}$ diet group (C). Immunoblotting and RT-PCR analysis revealed protein expression, and anti-oxidant analysis revealed MDA (malondialdehyde), GSH (glutathione), and free DPPH radical. As a results, Body weight and food consumption were not significantly different between groups. The levels of MDA and GSH were lower in HF + $EQS^{(R)}$ group than in HF group. Also, the $EQS^{(R)}$ demonstrated to be more effective than HF group for a DPPH radicals scavenging activities. In addition, protein and mRNA level of TNF-$\alpha$ in HF + $EQS^{(R)}$ group showed relatively more potent pro-inflammatory activity inhibition compared to HF group. These results suggest that green tea mixture (EQ diet-$S^{(R)}$) provide positive effects on anti-oxidative and inflammatory inhibition effects on obese animal model or obesity related diseases.

• 셀메드
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• 제2권1호
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• pp.2.1-2.11
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• 2012

Tea polyphenols especially catechins have long been studied for their antioxidant and radical scavenging properties. Scientists throughout the world have investigated the usefulness of the regular green tea consumption in several disease conditions. In-vitro and in-vivo experiments on catechins especially epigallocatechingallate have revealed a significant role in many ways. Reactive oxygen species have been increasingly implicated in the pathogenesis of many diseases and important biological processes. Toxic effects of these oxidants, commonly referred to as oxidative stress, can cause cellular damage by oxidizing nucleic acids, proteins, and membrane lipids. Oxidative stress has been related to aging and age related disorders. It is found that in a wide variety of pathological processes, including cancer, atherosclerosis, neurological degeneration, Alzheimer's disease, ageing and autoimmune disorders, oxidative stress has its implications. Catechins have been reported to be useful in combating aging and age related disorders like cancer, cardiovascular disorders and neurodegenerative diseases. In this mini review we will discuss such studies done across the globe.

• 한국식품영양과학회지
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• 제40권9호
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• pp.1328-1332
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• 2011

본 연구에서는 오리알에 녹차 추출물을 이용하여 가압침지처리를 함으로써 녹차의 기능성 성분을 침투시키고자 하였으며 가압침지 후 오리알의 성분변화와 항산화 활성의 변화를 연구하였다. 녹차의 활성성분을 함유하는 오리알을 제조하기 위해 녹차 10, 20, 30% 추출액에 오리알을 침지시켜 각각 1과 5 MPa 조건에서 30분 동안 상온에서 가압하여 녹차의 catechin 성분들이 침투되도록 하였다. 대조구(0.17 mg/100 g)와 비교하여 오리알 난백의 EGCG 함량은 20 mg/100 g(30% 녹차 추출물, 5 MPa)으로 약 100배 이상 증가하였으며 침지시료의 농도와 압력이 증가할수록 EGCG 함량이 증가함을 알 수 있었다. 항산화 활성과 세포 보호효과 및 ROS 제거 효과 모두 대조구보다 5 MPa 조건에서 증가하는 것으로 나타났다. 본 연구 결과는 비교적 간단한 공정과 경제적인 방법으로 녹차의 EGCG 함량이 증가된 오리알을 제조하는 방법을 연구하고 그 활성을 증명함으로써 국내 오리알을 이용한 고부가가치 가공식품 개발과 오리알의 소비촉진에 영향을 미칠 것으로 생각된다.

• 대한임상검사과학회지
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• 제46권4호
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• pp.131-135
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• 2014

Over-consumption of alcohol leads to many side-effects such as malnutrition, liver disease, and neuronal disorders and many investigators have tried to identify methods for preventing the side-effects of drinking. This study was carried out to investigate the effect of the beverage contained green tea catechins (GTC) on the alcohol administered rats. We observed that blood alcohol concentration level decreased significantly in plasma. GTC (200 mg/kg) also reduced the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) level of the intoxicated rats. These results suggest that GTC may be useful for the prevention and therapy of hepatotoxic pathogenesis.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권2호
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• pp.130-135
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• 2000

The characteristics of two different modes of perfusion culture, intermittent and continuous bleedings, were investigated by culturing the hybridoma cells producing von Willebrand Factor (vWF) monoclonal antibody (McAb) in a 15 L bioreactor without clogging the filter. Both culture methods exhibited similar profiles of cell density and metabolite concentrations during the culture period at the cell concentration of around 1${\times}$107 cells/mL. When the perfusion rate was increased, the intermittrnt bleeding culture showed problems of ammonia accumulation and decrease of cell viability. The continuous bleeding culture in terms of nutrient consumption and metabolite production kinetics. But the analysis of specific oxygen consumption rate showed that the specific oxygen consumption rate of intermittent bleeding culture was similar to that of exponential growth phase. The continuous bleeding culture showed higher specific oxygen consumption rate of intermittent bleeding culture. finally we proved the possibility of long-term operation of continuous bleeding culture and produced approximately 40 g of vWF McAb in a 15L bioreactor after one-month operation.

• Journal of Biosystems Engineering
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• 제41권2호
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• pp.85-92
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• 2016

Background: The same plant, Camellia sinensis, is used to produce all types of tea, and the differences among the various types arise from the different processing steps that are used. Based on the degree of fermentation, tea can be classified as black, green, white, or oolong tea. Of these, black tea is the most or fully fermented tea. The oxidized polyphenolic compounds such as theaflavins (TF) and thearubigins (TR) formed during fermentation are responsible for the color, taste, flavor, and aroma of black tea. Results: Research indicates that an optimum ratio of TF and TR (1:10) is required to ensure a quality cup of tea. The concentrations of TF and TR as well as desirable quality characteristics increase as fermentation time increases, reaching optimum levels and then degrading if the fermentation time is prolonged. It is also necessary to control the environment for oxidation. There are no established environment conditions that must be maintained during the fermentation of the ruptured tea leaves. However, in most cases, the process is performed at a temperature of $24-29^{\circ}C$ for 2-4 h or 55-110 min for orthodox tea or crush, tear, and curl (CTC) black tea, respectively, under a high relative humidity of 95-98% with an adequate amount of oxygen. Conclusion: The polyphenolic compounds in black tea such as TF and TR as well as un-oxidized catechins are responsible for the health benefits of tea consumption. Tea is rich in natural antioxidant activities and is reported to have great potential for the management of various types of cancers, oral health problems, heart disease and stroke, and diabetes and to have other health benefits such as the ability to detoxify, improve urine and blood flow, stimulate, and improve the immune system.

• Journal of Nutrition and Health
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• 제34권7호
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• pp.762-769
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• 2001

Recently developed TRAP assay(Total Radical-trapping Antioxidant Potential) is a new technique which enable effectively the measurement of total antioxidant status in the plasma. Researches using TRAP method have rarely been reported in Korea. Therefore, we investigated effects of various life-style and dietary factors on plasma TRAP level in Korean adult population. The subjects consisted of 161 health adult male(n=105) and female (n=56) aged 19-57. A self-administered questionnaire ascertained life-style factors including smoking habits, alcohol use, physical activity. Dietary factors were analyzed by 24 hour recall method. TRAP was determined spectrophotometrically in plasma at 734nm. Mean plasma TRAP concentrations were slightly higher in males (1.35$\pm$0.02mM) and females(1.30$\pm$0.02mM) without significance. There were significant correlations between plasma TRAP levels and life-style factors including exercise and smoking Plasma TRAP levels were affected more by exercise than by smoking. Moderate amount exerciser(exercise time $\geq$30min/day) had significantly higher level of plasma TRAP levels in male smokers(1.33$\pm$0.03mM) were significantly lower than those in male nonsmokers(1.39$\pm$0.01mM, p<0.05), but the difference was not seen in female subjects. Intakes of vitamin C(r=0.288, p=0.007) or folate (r=0.258, p=0.016) were positively correlated with plasma TRAP levels in nonsmokers, but those relations were not seen in smokers. Dietary factors such as vegetables (r=0.288, p=0.007)or folate (r=0.258, p=0.016) were positively correlated with plasma TRAP levels in nonsmokers, but those relations were not seen in smokers. Dietary factors such as vegetables (r=0.277, p=0.009) and legumes(r=0.263, p=0.013) consumption were positively related to plasma TRAP concentrations also in nonsmokers only. Regular green tea drinkers showed significantly greater level of plasma TRAP than the non green tea drinkers(1.36$\pm$0.01mM vs 1.30$\pm$0.03mM, p<0.05). These results suggest that the regular exercise($\geq$30min daily), nonsmoking, and consumption of vegetables, legumes and green tea would contribute to improving plasma TRAP levels in Korean adults.

• 한국식품과학회지
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• 제52권5호
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• pp.427-434
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• 2020

본 연구에서는 녹차 국내종(보향, 참녹), 외래종(후슌, 야부기다)의 채취시기를 달리하여 테아닌, GABA 등 유용 성분 함량을 분석하였고, 항산화능, α-glucosidase 활성 억제, HMG-CoA 저해도, 세포독성 측정, 뇌 신경세포 보호 효과, 항 스트레스 효과를 조사하여 유용 성분과의 상관성을 파악하고자 하였다. 테아닌과 GABA 함량은 모든 품종에서 채취시기가 늦어질수록 함량이 감소하는 경향을 나타내었다. 총 아미노산 함량에서는 채엽시기가 늦어질수록 보향 품종에서 증가하는 경향을 나타내었고 후슌, 야부기다 그리고 참녹은 여름차에서 감소 후 다시 가을차에서 증가하는 경향을 보였다. 총페놀과 플라보노이드의 함량과 항산화능을 조사했을 때 ABTS는 후슌, 보향, 참녹에서 플라보노이드 농도와 비례하는 경향을 보였으며, 재래 녹차와 야부기다는 총페놀의 농도와 비례하는 경향을 나타내었다. DPPH radical 소거능은 참녹을 제외한 모든 시료에서 여름차의 활성이 가장 높고 가을차에서 활성이 다시 감소하는 것을 확인하였다. 카테킨류 측정에서 EGCg 함량은 카테킨류에서 50% 이상을 차지했고, 총 카테킨 함량과 Ecg, EGCg는 종과 관계없이 채취 시기가 늦어질수록 증가하는 경향을 보였으며 EGC는 감소하는 경향을 보였다. 품종별 봄, 여름, 가을차를 시료로 하여 측정한 α-glucosidase 저해 활성과 HMG-CoA reductase 저해능은 채취 시기가 늦어질수록 증가함을 보였고 그 중 가을에 채취한 참녹에서의 저해 활성이 각각 72.93%, 69.78%로 두 저해능 측정에서 가장 높은 저해활성을 보였다. 또한 뇌신경세포(SH-SY5Y)를 이용한 세포 독성 측정에서 참녹 품종이 96.34%로 가장 높은 세포생존율을 보였고 항스트레스 측정에서 269.2 ng/mL로 가장 낮은 cortisol 함량이 확인되었다.

• Journal of Nutrition and Health
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• 제44권6호
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• pp.465-473
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• 2011

Dietary fatty acids are under intense research to identify anti-atherogenic mechanisms, so we investigated green tea powder (GT) as a protector against atherogenesis originating from lipid peroxidation such as 4-hydroxynonemal (4-HNE) and malondialdehyde (MDA) in different dietary fatty acid-treated apo E KO mice. Growth rate and dietary efficiency were lower in apo E KO mice with or without LA compared to wild type. Plasma total cholesterol (TC) and triacylglycerol (TG) did not correspond to values in other tissues, but TG in heart tissue decreased significantly by GT after linoleic acid (LA) or docosahexaenoic acid (DHA) was administered. LA induced apoptosis as evidenced by changes in aorta morphology and immunohistochemistry. Lipid peroxides (LPO) was increased in apo E KO mice with or without LA corresponding to the accumulation of 4-HNE or MDA in the proximal aorta above the atria. GT consumption tended to reduce the primary causal mechanism of atherogenic phenomena such as oxidizability in both LA and DHA treated atherogenic mice. A high polyunsaturated fatty acids (PUFA) diet involved the changes on stress-induced apoptotic signaling by increasing caspase 3, cytochrome c, and nuclear factor-${\kappa}B$ in the heart tissue, but decreasing the bcl-2 protein. However, GT remarkably reduced the expression of apoptotic signaling, in contrast to the PUFA diet. Therefore, the potential of GT as an anti-atherosclerotic dietary antioxidant was tested in this study.