• Journal of Nutrition and Health
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• 제41권7호
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• pp.602-611
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• 2008

본 연구에서 pair feeding함으로서 사료 섭취량이 체중이나 지단백 대사에 미칠 요인을 제거한 상태에서 녹차분말이나 녹차추출물이 갖는 항 비만효과나 지질 강하효과를 비교 조사하였다. 녹차분말이나 추출물에서 증체 억제효과를 보였는데 이는 녹차성분이 소장에서의 지방흡수를 억제하거나 지방산화를 촉진하고 대사율을 올려 열량소비를 증가시킨다는 기존 연구결과와 이해를 같이 하는데, 예비실험에서 사료섭취량 자체가 억제됨을 감안 할 때 녹차 추출물이나 분말의 항비만 효과에 대해서 긍정적이다. 본 연구에서 녹차 추출물의 높은 콜레스테롤 흡수 억제력에도 불구하고 녹차의 콜레스테롤 강하효과는 나타나지 않았는데 이는 체 콜레스테롤 pool size에 강한 homeostasis 기질이 작용한 것이라고 생각할 수 있다. 식이 콜레스테롤과 지방의 흡수억제에 있어서 녹차분말과 녹차 추출물의 장내 유용성과 체 콜레스테롤의 합성과 담즙 생성에 있어서 EGCG를 포함한 차 카테킨 작용기전을 이해하기 위해서 보다 많은 연구가 필요하리라 생각된다. 녹차 분말과 추출물은 항산화 지표에도 정도에 다소 차이가 있으나 긍정적인 효과를 보였는데 녹차 카테킨은 수용성으로 bioavailability가 비교적 높은 polyphenol계 항산화 물질로서 녹차 잎의 건조중량 50% 이상이 카테킨이고 이중 80% 이상이 catechin gallate 형태로 강한 항산화 효력을 지닌 것으로 나타나 있다. 노화를 활성산소에 의한 세포의 손상과정이라 볼 때 식품으로서 녹차는 매우 중요한 입지에 있다. 차로 마시는 녹차의 섭취방법에서 분말이나 추출물로 섭취방법을 다양화하고 있는데 분말과 추출물의 영양적 효과를 비교해 볼 때 유리 (free)된 카테킨 형태로 추출물이 유리할 수 있지만 녹차분말이 식품으로서의 높은 선호도와 함께 HDL-콜레스테롤을 증가시키는 효과가 있다면 분말차의 섭취도 좋은 방법이다. 음료로서 따져 볼 때 일회 분량 2 g의 녹차를 3회 우려 마시는 경우 이로부터 섭취할 수 있는 항산화물질은 EGCG기준으로 $109{\sim}147\;mg$정도이고 이를 비타민 C 로 환산하는 경우 $142{\sim}168\;mg$이다. 천연의 항산화 물질을 자연스럽게 섭취하는 방법으로서 차의 음용을 생활화하는 것은 비만이나 퇴행성 또는 노화관련 질환의 예방차원에서 바람직하리라 본다.

• The Korean Journal of Physiology and Pharmacology
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• 제9권2호
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• pp.117-123
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• 2005

A cumulative evidence indicates that consumption of tea catechin, flavan-3-ol derived from green tea leaves, lowers the risk of cardiovascular diseases. However, a precise mechanism for this cardiovascular action has not yet been fully understood. In the present study, we investigated the effects of different green tea catechins, such as epigallocatechin-3 gallate (EGCG), epigallocatechin (EGC), epicatechin-3 gallate (ECG), and epicatechin (EC), on angiotensin II (Ang II)-induced hypertrophy in primary cultured rat aortic vascular smooth muscle cell (VSMC). [$^3H$]-leucine incorporation was used to assess VSMC hypertrophy, protein kinase assay, and western blot analysis were used to assess mitogen-activated protein kinase (MAPK) activity, and RT-PCR was used to assess c-jun or c-fos transcription. Ang II increased [$^3H$]-leucine incorporation into VSMC. However, EGCG and ECG, but not EGC or EC, inhibited [$^3H$]-leucine incorporation increased by Ang II. Ang II increased phosphorylation of c-Jun, extracellular-signal regulated kinase (ERK) 1/2 and p38 MAPK in VSMC, however, EGCG and ECG , but not EGC or EC, attenuated c-Jun phosphorylation increased by Ang II. ERK 1/2 and p38 MAPK phosphorylation induced by Ang II were not affected by any catechins. Ang II increased c-jun and c-fos mRNA expression in VSMC, however, EGCG inhibited c-jun but not c-fos mRNA expression induced by Ang II. ECG, EGC and EC did not affect c-jun or c-fos mRNA expression induced by Ang II. Our findings indicate that the galloyl group in the position 3 of the catechin structure of EGCG or ECG is essential for inhibiting VSMC hypertrophy induced by Ang II via the specific inhibition of JNK signaling pathway, which may explain the beneficial effects of green tea catechin on the pathogenesis of cardiovascular diseases observed in several epidemiological studies.

• 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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• 제30권5호
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• pp.1035-1041
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• 2017

(-)-Epigallocatechin-3-gallate (EGCG) is a major catechin found in green tea. It is reported that EGCG possesses various health benefits including anti-cancer, antioxidant, anti-diabetes, and anti-obesity. The objective of this study was to investigate the effects of EGCG on adipogenesis via activation of AMP-activated protein kinase (AMPK) pathway in 3T3-L1 preadipocytes. In order to determine the effects of EGCG on adipogenesis, preadipocyte differentiation was induced in the presence or absence of EGCG ($0{\sim}100{\mu}M$) for a period of 6 days. EGCG significantly inhibited fat accumulation and suppressed the expression of adipogenic specific proteins including peroxisome proliferator-activated receptor (PPAR)-${\gamma}$. Also, EGCG markedly increased the activation of AMPK and acetyl-CoA carboxylase (ACC) and the production of intracellular reactive oxygen species (ROS). However, any pretreatment with a specific AMPK inhibitor, compound C, abolished the inhibitory effects of the EGCG on $PPAR{\gamma}$ expression. This study suggests that EGCG has anti-adipogenic effects through modulation of the AMPK signaling pathway and therefore, may be a promising antiobesity agent.

• 대한임상독성학회지
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• 제14권2호
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• pp.78-82
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• 2016

Purpose: Green tea is known as a potent anti-oxidant, anti-carcinogen, and genetic protector. Glyphosate (N-phosphonomethyl glycine) is a widely used non-selective herbicide that causes DNA damage. The present study was conducted to investigate the protective effects of green tea in human blood lymphocytes exposed to glyphosate using the Sister Chromatid Exchange (SCE) frequency method. Methods: Peripheral blood was obtained from 10 volunteers and cultured through four different conditions. Four groups were divided into control, glyphosate only (300 ng/mL), glyphosate and low ($20{\mu}m$) concentrations of epigallocatechin gallate (EGCG) and glyphosate and high ($100{\mu}m$) concentrations of EGCG. Results: The glyphosate exposed groups had a higher mean SCE frequency ($10.33{\pm}2.50$) than the control group ($6.38{\pm}2.28$, p<0.001). The low concentrations of EGCG groups had a lower mean SCE frequency ($9.91{\pm}1.93$) than the glyphosate-only group, although this difference was not significant (p=0.219). However, the high concentration group ($9.49{\pm}1.85$) had a significantly lower SCE frequency than the glyphosate-only group (p=0.001). Conclusion: EGCG has a gene protective effect in human lymphocytes exposed to the genotoxicity of glyphosate in the case of high concentrations.

• 동아시아식생활학회지
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• 제18권3호
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• pp.391-396
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• 2008

This study was carried out to help restore and spread broaden the consumption of Chungtaejeon, a our traditional tea, Chungtaejeon in Korea, and as well as to gather the basic data on Chutaejeon tea. We have also compared the various ingredients components and physiological activities of Chungtaejeon tea extracts with that of green tea extracts. According to the results, the total phenol contents in of the Chungtaejeon and green tea extracts were 90.56 and 98.70 mg/100 mL, respectively, and their tannin contents levels in Chungtaejeon and green tea extracts were 214.14 mg/100 mL and 259.60 mg/100 mL, respectively, showing a difference in content. The catechin contents of the Chetaejeon and green tea extracts were in the order of EGC($15.80{\sim}16.50\;mg/100mL$), EGCG($10.40{\sim}10.60\;mg/100 mL$), and ECG($9.55{\sim}9.88\;mg/100 mL$), however, with the exception of EC(7.86 mg/100 mL) in the green tea extracts, there were not significant differences between that in them Chetaejeon and green tea extracts. Quercetin was the main flavonoid ingredient component in those both the Chungtaejeon and green tea extracts was quercetin, at levels of 0.08 mg/100 mL and 0.06 mg/100 mL and its contents in Chungtaejeon and green tea extracts were 0.08 mg/100 mL and 0.06 mg/100 mL, respectively. The primary amino acid in both tea extracts was theanine main amino acid at levels of, theanine contents were most increased in 8.02 mg/100mL and 10.80 mg/100 mL, respectively, Chungtaejeon tea extracts by 8.02 mg/100 mL and green tea extracts by 10.80 mg/100 mL. And the arginine contents of the Chungtaejeon and green tea extracts in Chungtaejeon and green tea extracts were 1.78 mg/100 mL and 1.86 mg/100 mL, respectively. In terms of mineral composition, potassium content was highest contents in the Chungtaejeon and green tea extracts by 19.80 and 18.04 mg/100 mL, respectively. Finally, the Chungtaejeon tea extracts offered the greatest anti-oxidation and ACE inhibition activities were most increased in the Chungtaejeon tea extracts, and the green tea extracts showed the highest level of nitrite radical scavenging activity at 90% was extremely much increased in the green tea extracts by 90%.

• Journal of Nutrition and Health
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• 제38권2호
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• pp.104-111
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• 2005

Tumor invasion is composed of four steps: cell adhesion to the extracellular matrix, degradation of the extracellular matrix components, tumor cell motility followed by cell detachment. Matrix metalloproteinases (MMPs) are important proteinases that associated with degradation of matrix component. Epigallocatechin gallate (EGCG) is a major polyphenotic constituent of green tea. In the study, we examined the anti-invasive and MMP activity suppression effects of EGCG in MDA-MB-231 human breast cancer cells. MDA-MB-23l human breast cancer cells were cultured with various concentrations 0 - 100 μM of EGCG. EGCG significantly inhibited the cell adhesion to the fibronectin. Cell motility through gelatin filter and invasion to Matrigel were inhibited dose-dependently by EGCG treatment. EGCG also inhibited the activities of MMP-2, -9 and the amount of MMP-9 (α = 0.05). Therefore, EGCG may contribute to the potential beneficial food component to prevent the invasion and metastasis in breast cancer. (Korean J Nutrition 38(2): 104～111, 2005)

• 한국식품과학회지
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• 제48권4호
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• pp.329-334
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• 2016

천연 녹차추출물인 epigallocatechin gallate (EGCG)의 메추리알 장조림에서 천연식품첨가제로서의 적용 가능성을 탐색하고자 S. Enteritidis에 대한 항미생물 활성을 냉장온도($4^{\circ}C$)와 일반실내온도($25^{\circ}C$)에서 평가하였다. 순수배양액에서의 실험결과 첨가된 EGCG의 농도($200-800{\mu}g/mL$)에 따라 $4^{\circ}C$에서 5일에서 16일 사이에서 그리고 $25^{\circ}C$에서 1일부터 6일 사이에서 S. Enteritidis균이 검출한계 이하로 억제되는 것이 관찰되었다. 이와 대조적으로 간장소스에서의 실험에서는 $25^{\circ}C$에서 첨가된 EGCG의 농도와 관계없이 S. Enteritidis균이 억제되지 않았으며, $4^{\circ}C$에서는 $400{\mu}g/mL$ 이상의 농도일 때 16일에 S. Enteritidis균이 검출한계 이하로 억제되는 것이 관찰되었다. 메추리알 장조림의 경우, $25^{\circ}C$에서 간장소스의 결과와 동일하게 어떠한 EGCG의 항미생물 활성이 나타나지 않았지만, $4^{\circ}C$에서 $400{\mu}g/mL$의 EGCG 농도 첨가 시 16일에 S. Enteritidis 균이 검출한계 이하로 억제되는 것이 확인되었다. 따라서, 메추리알 장조림 완제품에서 EGCG는 $4^{\circ}C$ 이하의 저온유통체계(cold chain system)하에서 S. Enteritidis과 같은 식중독세균을 제어할 수 있는 적합한 천연 식품첨가제로서 활용될 수 있을 것으로 기대된다.

• 대한화학회지
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• 제51권2호
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• pp.165-170
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• 2007

고정상 추출에 케르세틴 분자각인 고분자를 흡착제로 하여 녹차에서 카페인과 +C, EGC, EGCG와 같은 카테킨 화합물을 추출하였다. Quercetin을 주형분자로, MAA를 단량체로, EGDMA를 가교제로 하고 AIBN을 개시제로 하여 MIP를 합성하였다. 녹차에서 카페인과 카테킨 화합물을 추출하기 위하여 고정상 추출에서의 주입, 세척, 용출용매로 각각 물, 메탄올, 메탄올:아세트산=90:10(vol.%)을 사용하였다. 고성능 액체 크로마토그래피 분석조건은 C18 컬럼(5 μm, 250×4.6 mm, RS-tech 회사), 메탄올/물(40/60, vol.%)을 이동상 조건으로하고 유속은 0.5 ml/min으로 하였다. 분자각인 고정상 추출을 통과함으로써, 카페인과 카테킨 화합물의 분리도는 증가하였다. 또한 케르세틴 분자각인 고분자는 생성된 공극 구조와 유사한 화학적구조식을 가진 +C화합물에 대하여 더 우수한 선택성을 가졌다.

• The Korean Journal of Physiology and Pharmacology
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• 제19권3호
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• pp.203-210
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• 2015

AMP-activated protein kinase (AMPK) is a key regulator of energy metabolism. Previous studies have shown that activation of AMPK results in suppression of cardiac myocyte hypertrophy via inhibition of the p70S6 kinase (p70S6K) and eukaryotic elongation factor-2 (eEF2) signaling pathways. Epigallocatechin-3-gallate (EGCG), the major polyphenol found in green tea, possesses multiple protective effects on the cardiovascular system including cardiac hypertrophy. However, the molecular mechanisms has not been well investigated. In this study, we found that EGCG could significantly reduce natriuretic peptides type A (Nppa), brain natriuretic polypeptide (BNP) mRNA expression and decrease cell surface area in H9C2 cardiomyocytes stimulated with phenylephrine (PE). Moreover, we showed that AMPK is activated in H9C2 cardiomyocytes by EGCG, and AMPK-dependent pathway participates in the inhibitory effects of EGCG on cardiac hypertrophy. Taken together, our findings provide the first evidence that the effect of EGCG against cardiac hypertrophy may be attributed to its activation on AMPK-dependent signaling pathway, suggesting the therapeutic potential of EGCG on the prevention of cardiac remodeling in patients with pressure overload hypertrophy.