• 동아시아식생활학회지
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• 제16권5호
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• pp.550-558
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• 2006

The study investigated the serum lipid metabolism and enzyme activities of Korean teas for their preventative activity against chronic disease and obesity. Male Sprague-Dawley rats were raised for 8 weeks on four experimental diets: normal diet, hyperlipidemic diet, and hyperlipidemic diet to which green and black teas (2% each) were added. Various biological actions, including lipid metabolism and enzyme activities of the serum, were investigated. Diet-induced, hyperlipidemic rats fed with green and black teas, showed significant decrease in food efficiency ratio, triglyceride, total lipid, and phospholipid compared to control, i.e. the normal and diet-induced, hyperlipidemic rats. Total cholesterol, LDL-cholesterol, Al(atherogenic index), LHR, VLDL-cholesterol, ester-cholesterol, and free-cholesterol also showed a significant decrease. However, there was no significant difference between the tea-fed, diet-induced, hyperlipidemic dieted groups. HDL-cholesterol concentration was increased significantly in the tea-dieted and normal groups compared to the control. There was a little difference in lipase activity between the normal and control groups, although green and black tea-dieted experimental groups were both increased compared to the control. The contents of total lipid, triglycerides, and total cholesterol were decreased in the normal and experimental groups compared to the control. The GOT, GPT, ALP and LDH serum enzyme activities of the experimental groups were significantly reduced compared to those of the control groups.

• 한국식품저장유통학회지
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• 제16권2호
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• pp.230-237
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• 2009

본 연구에서는 국내에서 시판되고 있는 4종류의 차 즉, 녹차, 보이차, 우롱차 및 홍차 열수추출물의 페놀성 화합물, 항산화 및 퇴행성 뇌신경질환 저해활성에 대하여 조사하였다. 시판 차 열수추출물의 총 페놀성 화합물 함량은 $72.03{\sim}85.62\;mg/g$이었으며, 녹차, 보이차, 우롱차 및 홍차 열수추출물의 총 플라보놀 함량은 각각 350.96, 254.17, 334.48 및 240.23 mg/100 g이었다. 녹차, 보이차, 우롱차 및 홍차 열수추출물의 총 카테킨 함량은 각각 2,920.35, 1,016.23, 2,824.22 및 1,006.51 mg/100 g이었으며, 카페인함량은 녹차 열수추출물에서 가장 높은 함량을 보였다. $ABTS{\cdot}+$ 라디칼 소거활성도 농도 의존적인 경향을 보였으며, FRAP은 다른 차 열수추출물에 비하여 녹차 열수추출물에서 가장 높게 나타났다. $\beta$-carotene과 linoleic acid system을 이용하여 측정한 항산화 활성 및 퇴행성 뇌신경질환효소 억제활성도 녹차 열수추출물에서 가장 높은 효과를 보였다. 따라서 시판 차 4종의 열수추출물을 이용하여 항산화 및 퇴행성 뇌신경질환효소 억제활성을 측정한 결과 녹차 열수추출물이 가장 높은 활성을 보였으며, 홍차 열수추출물이 가장 낮게 나타났다.

• 한국식생활문화학회지
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• 제22권4호
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• pp.449-453
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• 2007

Using green tea(GT), oolong tea(OT), black tea(BT) and green tea bag(GTB) out of tea products in market, this study quantified polyphenol and catechins as anti-oxidant substances and analyzed their respective anti-oxidant capacities. As a result, more epigallocathechin(EGC) was found in GT and GTB as well as caffein(CAF) in GT and BT. GT contained more epigallocathechin gallate(EGCG) than other tea types. Both FRAP and ORAC, as two methods of analyzing anti-oxidant capacities, showed that GTB had highest anti-oxidant capacities, while OT had lowest of all. By brand, it was found that all the 3 brands of GT had similarly high anti-oxidant capacities, but there were differences in the anti-oxidant activities of GTB and BT depending on brand. Out of catechin components, it was found that epicatechin(EC), epicathechin gallate(ECG) and EGCG were major components affecting anti-oxidant capacities.

• 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.

• 패션비즈니스
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• 제23권1호
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• pp.64-73
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• 2019

The objective of this study was to investigate dyeing characteristics of silk, cotton and rayon fabrics using dyeing solution extracted from different varieties of tea. Comparative results of CIE Lab values of 360 pieces of dyed fabrics were studied to quantify the effects of dye concentrations (100%, 150%, and 200%) and mordants (Fe, Cu, Sn, Al). In addition, the color difference values (${\Delta}E$) of the dyed and mordanted fabrics were evaluated. The results of the study were as follows: First, among all of the 360 pieces of silk, cotton and rayon fabrics, the best dyeing effects was observed on silk fabrics. Second, the dyeing effect of the eight different types of tealeaves belonging to green tea, oolong tea, black tea, and dark tea tended to enhance as the degree of fermentation increased. Third, when the fabrics were mordanted with Fe, Cu, Sn, Al mordants, various colors such as brown, brownish red, brownish yellow, gray, and reddish brown were obtained.

• Asian-Australasian Journal of Animal Sciences
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• 제27권7호
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• pp.937-945
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• 2014

Green and black tea by-products, obtained from ready-made tea industry, were ensiled at $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$. Green tea by-product silage (GTS) and black tea by-product silage (BTS) were opened at 5, 10, 45 days after ensiling. Fermentation characteristics and nutrient composition, including tannins, were monitored and the silages on day 45 were subjected to in vitro ruminal fermentation to assess anti-nutritive effects of tannins using polyethylene glycol (PEG) as a tannin-binding agent. Results showed that the GTS and BTS silages were stable and fermented slightly when ensiled at $10^{\circ}C$. The GTS stored at $20^{\circ}C$ and $30^{\circ}C$ showed rapid pH decline and high acetic acid concentration. The BTS was fermented gradually with moderate change of pH and acid concentration. Acetic acid was the main acid product of fermentation in both GTS and BTS. The contents of total extractable phenolics and total extractable tannins in both silages were unaffected by storage temperatures, but condensed tannins in GTS were less when stored at high temperature. The GTS showed no PEG response on in vitro gas production, and revealed only a small increase by PEG on $NH_3$-N concentration. Storage temperature of GTS did not affect the extent of PEG response to both gas production and $NH_3$-N concentration. On the other hand, addition of PEG on BTS markedly increased both the gas production and $NH_3$-N concentration at any ensiled temperature. It can be concluded that tannins in both GTS and BTS suppressed rumen fermentation, and tannins in GTS did more weakly than that in BTS. Ensiling temperature for both tea by-products did not affect the tannin's activity in the rumen.

• 한국식품과학회지
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• 제26권6호
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• pp.740-744
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• 1994

본 연구는 녹차음료가 음용수나 식품에 오염된 중금속 (Pb, Cd)의 장내 흡수 억제효과가 있는지를 조사하기위해 장내 흡수 조건을 고려한 한외여과막을 이용한 in vitro 실험을 실시하였다. 납과 카드뮴이 수질기준의 10배 또는 100배로 오염된 음료수애서 단독오염의 경우 납은 녹차, 홍차에서 $50{\sim}70%$, 보리차에서 $30{\sim}40%$의 제거율을 보였으며 카드뮴은 녹차, 홍차에서 $30{\sim}40%$, 보리차에서 $10{\sim}20%$의 제거율을 나타냈다. 납과 카드뮴이 혼합오염된 경우는 단독오염보다 제거효과가 낮았는데 이는 다엽성분 및 여과막에 대한 두 금속원소의 흡착경합에 기인하는 것으로 생각된다. 다류 원료에서 음료틀 침출하는$70^{\circ}C$, 2분과 $95^{\circ}C$, 10분외 두 조건은 비슷한 중금속 제거율을 보였다. 녹차의 페놀성 물질인 tannic acid 와 gallicd acid도 비슷한 중금속 제거효과를 보였다.

• 한국식품조리과학회:학술대회논문집
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• 한국식품조리과학회 2004년도 학술대회
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• pp.85-85
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• 2004

• 대한화학회지
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• 제63권2호
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• pp.78-84
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• 2019

High-resolution $^1H$ NMR spectroscopic technique has been widely used as one of the most powerful analytical tools in food chemistry as well as to define molecular structure. The $^1H$ NMR spectra-based metabolomics has focused on classification and chemometric analysis of complex mixtures. The principal component analysis (PCA), an unsupervised clustering method and used to reduce the dimensionality of multivariate data, facilitates direct peak quantitation and pattern recognition. Using a combination of these techniques, the various green teas and black teas brewed were investigated via metabolite profiling. These teas were characterized based on the leaf size and country of cultivation, respectively.

• BMB Reports
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• 제36권1호
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• pp.66-77
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• 2003

Tea is one of the most popular beverages consumed in the world and has been demonstrated to have anti-cancer activity in animal models. Research findings suggest that the polyphenolic compounds, (-)-epigallocatechin-3-gallate, found primarily in green tea, and theaflavin-3,3'-digallate, a major component of black tea, are the two most effective anti-cancer factors found in tea. Several mechanisms to explain the chemopreventive effects of tea have been presented but others and we suggest that tea components target specific cell-signaling pathways responsible for regulating cellular proliferation or apoptosis. These pathways include signal transduction pathways leading to activator protein-1 (AP-1) and/or nuclear factor kappa B(NF-${\kappa}B$ ). AP-1 and NF-${\kappa}B$ are transcription factors that are known to be extremely important in tumor promoter-induced cell transformation and tumor promotion, and both are influenced differentially by the MAP kinase pathways. The purpose of this brief review is to present recent research data from other and our laboratory focusing on the tea-induced cellular signal transduction events associated with the MAP kinase, AP-1, and NF-${\kappa}B$ pathways.