• 한국식품영양과학회지
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• 제31권4호
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• pp.672-678
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• 2002

본 연구에서는 free radicals의 산화적인 손상에 의한 세포사멸에 있어서 녹차성분의 하나인 (-)epigallocatechin gallate의 억제효과를 규명하였다. 우선 radicals 소거작용에 있어서 (-)epigallocatechin gallate는 탁월한 항산화력을 발휘하였다. 혈관손상과 직결되는 혈관내피세포를 이용하여 hydroxyl radical의 $H_2O$$_2$에 의한 산화적인 손상을 유발시켜 세포생존율을 조사하였는데, (-)epigallocatechin gallate는 100 $\mu\textrm{m}$ 이하의 농도에서는 그 자체 독성이 없었고 $H_2O$$_2$의 산화적 독성효과를 경감시키는 것으로 나타났다. 그러나 flavone인 apigenin은 고농도에서 독성을 가지며 radical 소거활성이 미약하고 $H_2O$$_2$의 산화독성은 경감시키지 못하였다. 다양한 세포사멸 검출법을 이용하여 세포 및 세포핵의 형태학적 양상을 조사한 결과, 0.25mM $H_2O$$_2$에 의한 24시간 이내의 세포죽음은 세포사멸현상에 의하여 초래되었다. 그러나 이러한 세포사멸과정을 겪고 있는 혈관내피세포에 50 $\mu\textrm{m}$ (-)epigallocatechin gallate를 처리한 경우에 세포핵의 응축이나 DNA fragmentation은 사라지고 세포사멸작용을 억제시키는 효과를 보여주었다. 예상한 바와 같이 apigenin의 flavone은 세포사멸 억제효과를 나타내지 못하였다. (-)Epigallocatechin gallate는 녹차에 함유된 catechins의 하나로서 free radicals의 산화적 손상에 의한 세포사멸에 있어서 탁월한 방어적 인 세포생리학적인 기능을 지니고 있으며, 혈관노화 및 혈관손상과 함께 유발되는 세포사멸성 심혈관질환의 예방과 치료에 기능성 식품 신소재로서 활용될 수 있으리라 본다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권10호
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• pp.4199-4202
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• 2015

Background: Hepatitis B virus infection is one of the major world health problems. Epigallocatechin-3 gallate is the major component of the polyphenolic fraction of green tea and it has an anti-viral, anti-mutagenic, anti-tumorigenic, anti-angiogenic, anti-proliferative, and/or pro-apoptotic effects on mammalian cells. In this study, our aim was to investigate the inhibition of HBV replication by epigallocatechin-3 gallate in the Hep3B2.1-7 hepatocellular carcinoma cell line. Materials and Methods: HBV-replicating Hep3B2.1-7 cells were used to investigate the preventive effects of epigallocatechin-3 gallate on HBV DNA replication. The expression levels of HBsAg and HBeAg were determined using ELISA. Quantitative real-time-PCR was applied for the determination of the expression level of HBV DNA. Results: Cytotoxicity of epigallocathechin-3-gallate was not observed in the hepatic carcinoma cell line when the dose was lower than $100{\mu}M$. The ELISA method demonstrated that epigallocatechin-3 gallate have strong effects on HBsAg and HBeAg levels. Also it was detected by real-time PCR that epigallocatechin-3 gallate could prevent HBV DNA replication. Conclusions: The obtained data pointed out that although the exact mechanism of HBV DNA replication and related diseases remains unclear, epigallocatechin-3 gallate has a potential as an effective anti-HBV agent with low toxicity.

• 약학회지
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• 제37권4호
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• pp.365-369
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• 1993

Five phenolic compounds have been isolated from the stems and leaves of Rosa rugosa Thunb. (Rosaceae) in Korea. They were methyl gallate and catechin from the stems, and quercetin, methyl gallate and hyperin from the leaves respectively. The structures were established by spectroscopic and chemical methods.

• Journal of the Korean Wood Science and Technology
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• 제37권2호
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• pp.164-170
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• 2009

The bark of Acer barbinerve was extracted with 70% aqueous acetone and the organic extracts were concentrated to small volume using rotary evaporator and then fractionated successively with n-hexane, dichloromethane, ethyl acetate and water. The chromatographic separation of ethyl acetate soluble fraction led to the isolation of five phenolic compounds. By means of spectroscopic method, the structures of these compounds were identified to methyl gallate (1), methyl gallate-4-O-${\beta}$-D-glucose (2), (+)-catechin (3), (-)-epicatechin (4) and (-)-epicatechin-3-O-gallate (5). These compounds (1-5) have not been reported in this plant yet.

• KSBB Journal
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• 제14권5호
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• pp.517-522
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• 1999

실험에 사용된 녹차는 전남 보성에서 재배된 것으로 국내시장에서 구입하였다. 녹차 5g을 순수한 물 5$0^{\circ}C$에서 추출한 후 클로로포름과 에틸아세테이트로 분배하였다. 추출액을 크로마토그래픽 컬럼 (4.6$\times$250 mm, 15$\mu\textrm{m}$, Lichrospher 100RP-18)을 이용하여 정제하였다. 정제된 추출액으로부터 $\mu$-Bondapak $C_18$(3.9$\times$300mm, 10$\mu\textrm{m}$) 컬럼을 이용하여 녹차에 포함된 카테킨 화합물을 분리하였으며, EGC(Epigallocatechin, C(catechin), EC(Epicatechin), EGCG(Epigallocatechin Gallate) and ECG(Epicatechin Gallate)의 순으로 용출되었다. 본 연구의 결과로서는 목적물질인 EGCG를 분리하기 위해 이동상의 조성은 0.1%의 아세트산이 포함된 물/아세토나이트릴, 87/13 %(v/v)이었다. 유량은 1.0 $m\ell$/min, UV 검지기는 280nm로 고정하였다. 위의 실험조건으로 5g의 전남 보성산 녹차로부터 순도 98% 이상의 121.3mg EGCG를 얻을 수 있었다.

• 한국식품과학회지
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• 제24권6호
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• pp.558-562
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• 1992

Xanthine oxidase는 퓨린 대사에 관여하여 xanthine 혹은 hypoxanthine을 산화하여 요산을 생성하게 하는 효소이다. 이상 퓨린 대사로 인해 형성된 요산은 관절에 축적되어 통풍을 동반하는 통증을 유발한다. 본 연구는 천연물로부터 통풍치료제의 개발을 목적으로 우롱차로 부터 6종의 flavan-3-ol 화합물을 분리하였고 기기분석에 의해 화학구조를 밝혔다. 각 화합물은 (-)-epicatechin, (-)-epicatechin-3-O-gallate, procyanidan B-1, B-3, procyanidin B-3-3'-O-rhamnose procyanidin B-1-3-O-gallate 였다. Xanthine oxidase 저해 영향을 관찰한 결과 gallte가 결함된 flavan-3-ol 화합물이 저해활성이 강하였고 procyanidin B-1-3-O-gallate는 $50\;{\mu}M$에 완전한 저해효과를 나타내었고 xanthine oxidase에 경쟁적으로 저해한다는 것이 밝혀졌다.

• Nutritional Sciences
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• 제9권3호
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• pp.145-151
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• 2006

Matrix metalloproteinases (MMP) play an important role in the extracellular matrix (ECM) degradation undetphysiological and pathological conditions. The present study examined the influence of (-)epigallocatechin gallate and quercetin on phorbol-12-myristate 13-acetate (PMA)-induced secretion of MMP-2 and MMP-9, when human umbilical vein endothelial cells (HUVEC) were treated with (-)epigallocatechin gallate and quercetin at supraphysiological concentrations of $25{\mu}mol/L$. No cytotoxicity was observed by MIT assay in response to a treatment with PMA in the presence of (-)epigallocatechin gallate and quercetin. Western blot analysis and gelatin zymography revealed that exposure of HUVEC to PMA enhanced the levels and gelatinolytic activities of pro and active forms of MMP-2 and active form of MMP-9. (-)Epigallocatechin gallate attenuated PMA-stimulated secretion of active forms of MMP-2 and MMP-9 concomitantly with a loss of activities of these enzymes, which was related to the decreased mRNA levels of MMP. Quercetin was more potent than (-)epigallocatechin gallate in alleviating MMP-9 protein secretion and activity with a decrease in MMP-9 mRNA accumulation. Taken together, the results indicated that (-)epigallocatechin gallte and quercetin exhibited inhibitory effects on MMP activity and may qualify as chemopreventive and cardiovascular protective agents.

• Archives of Pharmacal Research
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• 제28권7호
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• pp.775-783
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• 2005

The ethanol extract of the peony root (Paeonia Lactiflora Pall, Paeoniaceae) as well as its major active components including gallic acid and methyl gallate were evaluated for their protective effects against free radical generation and lipid peroxidation. In addition, the protective effects against hydrogen peroxide-induced oxidative DNA damage in a mammalian cell line were examined. The ethanol extracts of the peony root (PREs) and its active constituents, gallic acid and methyl gallate, exhibited a significant free radical scavenging effect against 1,1-diphenyl-2-picryl hydrazine (DPPH) radical generation and had an inhibitory effect on lipid peroxidation, as measured by the level of malondialdehyde (MDA) formation. The PREs did not have any pro-oxidant effect. They strongly inhibited the hydrogen peroxide-induced DNA damage from NIH/3T3 fibroblasts, as assessed by single cell gel electrophoresis. Furthermore, the oral administration of 50% PRE (50% ethanol extract of peony root), gallic acid and methyl gallate potently inhibited the formation of micronucleated reticulocytes (MNRET) in the mouse peripheral blood induced by a $KBrO_3$ treatment in vivo. Therefore, PREs containing gallic acid and methyl gallate may be a useful antigenotoxic antioxidant by scavenging free radicals, inhibiting lipid peroxidation and protecting against oxidative DNA damage without exhibiting any pro-oxidant effect.

• 한국산학기술학회논문지
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• 제5권6호
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• pp.546-551
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• 2004

본 연구에서는 녹차분말이 포함된 녹차유부의 시제품 섭취가 실험쥐의 혈청지질에 미치는 영향을 조사하였다. 녹차분말이 포함된 유부 제품의 성분을 HPLC로 분석한 결과 녹차의 기능성 성분인 epigallocatechin, epicatechin, epicatechin gallate, epigallocatechin gallate 등이 공정단계에서 파괴되지 않고 잘 보존됨을 확인할 수 있었다. 개발된 녹차유부 시제품을 실험쥐에 섭취시킨 후 혈청의 HDL-cholesterol, LDL-cholesterol, triglyceride과 포도당농도를 측정한 결과 일반 유부를 섭취한 대조군에 비하여 혈중 LDL-cholesterol 농도와 혈당량이 유의성 있게 감소되었다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.212.2-212.2
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• 2003

In the course of searching for BACE1 (${\beta}$-secretase) inhibitors from natural products, the ethyl acetate soluble fraction of green tea, which was suspected to be rich in catechin content, showed potent inhibitory activity. (-)-Epigallocatechin gallate, (-)-epicatechin gallate, and (-)-gallocatechin gallate ware isolated with IC$\_$50/ values of 1.6${\times}$10$\^$-6/ M, 4.5${\times}$10$\^$-6/ M, and 1.8${\times}$10$\^$-6/ M, respectively. Seven additional authentic catechins were tested for a fundamental structure-activity relationship. (-)-Catechin gallate, (-)-gallocatechin, and (-)-epigallocatechin significantly inhibited BACE1 activity with IC$\_$50/ values of 6.0${\times}$10$\^$-6/ M, 2.5${\times}$10$\^$-6/ M, and 2.4${\times}$10$\^$-6/ M, respectively. (omitted)