• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.21-26
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• 2010

Microbial-fermented tea (MFT), which is made by microorganisms through fermentation, is a popular beverage in Asia, especially in the Yunnam province, China. In this study, changes of the chemical constituents and antioxidant activity during the manufacturing process of MFT were investigated. MFT were respectively prepared from fresh leaves of three different tea species (Yabukita, Daecha, and Korean wild cultivar) and a processed green tea (Korean wild cultivar). The color of the tea infusions gradually changed to red and yellow as a function of fermentation time. Total nitrogen and caffeine contents were not significantly changed. Whereas, the chlorophyll, tannin, and total catechins contents gradually decreased. Interestingly, the epicatechin and epigallocatechin contents increased up to 25 days of fermentation and then decreased. Change of the chemical constituents of all samples showed the same patterns. The antioxidant activity of MFT from Daecha and Yabukita slightly decreased as increasing fermentation time. However, the range over which the antioxidant activity of MFT from Korean wild cultivar and green tea were not changed. This research suggests that it may be possible to manufacturing possibility of MFT using Korean wild cultivar and processed green tea.

• Journal of Soil and Groundwater Environment
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• v.22 no.5
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• pp.128-134
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• 2017

This work presents the adsorption capability of green tea and ginseng leaves to adsorb heavy metals such as Cd(II), Cu(II), and Pb(II) in aqueous solution. FT-IR analysis indicates the presence of oxygen containing functional groups (carboxyl groups) in two kinds of leaves. High pH condition was favorable to the adsorption of heavy metal ions due to the enhanced electrostatic attraction and the precipitation reaction of metal ions. The adsorption of Cd(II), Cu(II), and Pb(II) reached equilibrium within 10 min, achieving high removal efficiencies of 80.3-97.5%. The adsorption kinetics data of heavy metal ions were fitted well with the pseudo-second-order kinetic model. The maximum adsorption amounts of Cd(II), Cu(II), and Pb(II) ions were 8, 3.5, and 15 mg/g, respectively, in the initial concentration range from 0.15 to 0.75 mM. Based on the fitting data obtained from isotherm models, heavy metal adsorption by green tea and ginseng leaves could occur via multi-layer sorption.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.3
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• pp.367-374
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• 2011

The purpose of this study was to determine the optimum condition for producing tea leaf Jeung-pyun that does not contain added parched tea leafs (0, 0.5, 1, 1.5, and 2%) while producing Jeung-pyun that has a variety of functional ingredients and to investigate the possibility of making practical application of tea leafs. Moisture contents were 56 ~66% and there were no significant differences among the samples. The pH of Jeung-pyun samples was 5.65~5.74. The L-value decreased as the amount of added tea leaf increased, and the a-value was low in the group made with added tea leafs. The b-value was high in the 1% added group and had a tendency to increase vs the control group as amount of added tea leaf increased. In the groups with added tea leaf the volume was evaluated as being higher in the order of 1>1.5>2%. The specific volume of the group with added tea leaf was evaluated as being higher in the order of 1>1.5>2%. Sensory characteristics of the group with added tea leaf were evaluated as being high. For characteristics of cell uniformity, rice wine flavor, and sweetness, the control group was evaluated as being high, and for characteristics of color, moistness, and softness the 1% added group was evaluated as high. Astringency was evaluated as being high in the 2% added group. Texture profile analysis was conducted after samples were maintained in an incubator at $20^{\circ}C$ for 0, 1, 3, 5, and 7 days. Characteristics for hardness, gumminess, chewiness tended to increase with longer periods of storage. Characteristics for cohesiveness, springiness tended to decrease as the storage period increased. As determined by this study, addition of 1% tea leaf was the most favorable method for making use of tea leafs the production of Jeung-pyun and a potentiality for the use of tea leafs in food was discorvered.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.111-111
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• 2003

Green tea have been widely reported as functional foods because of their various bioactivities. In the present study, we used 3T3-Ll cells model of white adipocytes to clarify whether green tea and its main pharmaceutically effective compounds (EGCG, caffeine and theanine) prevent obesity. Cellular viability, glycerol-3-phosphate dehydrogenase activity, glycerol release and HSL mRNA levels were checked. Glycerol release into the medium was significantly increased by the cells treated with green tea extract. Glycerol release into the medium was significantly increased by the cells treated with green tea extract. Caffeine and theanine from green tea showed some level of lipolytic activity, and glycerol-3-phosphate dehydrogenase activity was remarkably decreased by EGCG. These results suggest that green tea has anti-obesity effect through inhibition of adipogenesis and stimulation of lipolysis. Catechins and theanine of green tea might be the factors responsible for the modulation of lipid metabolism and adipocyte differentiation.

• Fashion & Textile Research Journal
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• v.11 no.2
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• pp.344-349
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• 2009

Optimum dyeing conditions of green tea extracts were investigated toward nylon, cotton, rayon, and tencel fabrics. Affinity of green tea extracts was exhibited much higher onto nylon fabric than the other cellulosics. As for nylon, the adsorption was increased with the increase of dyeing temperature and optimum dyeing pH was around 4~6. Buildup property of green tea extract was good showing a linear relationship between concentration of the extracts and color strength of dyed fabrics within experimental range. Color fastnesses were good to excellent in general except to light.

• Korean Journal of Veterinary Service
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• v.28 no.2
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• pp.91-98
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• 2005

Green tea was known which regulated adipocyte differentiation metabolism. The mechanism on the lipid decreased contents of TAG in the plasma. In addition, green tea increased the expression leptin mRNA, PPAR $\delta$ mRNA and TGF $\beta$. The tea tested was korean powdered green tea. In this experiment, Sprague-Dawley (SD) rats were fed $3\%$ green tea(powdered) for 3 weeks on the basal diet and obese diet and green tea grouts-fed pork meats. duck meats. The expression of leptin mRNA and PPAR $\delta$ mRNA were up-regulated in the green tea-fed groups compared with those of the not green tea-fed groups. There were no significantly difference on the expression of leptin mRNA and PPAR $\delta$ mRNA in green tea grouts-fed pork meats, duck meats as compared with the not fed green tea grouts meats. TGF $\beta$ mRNA. TNF $\alpha$ mRNA and adipsin mRNA were not expressed in the pork meats, duck meats. The expression of TGF $\beta$ mRNA, TNF $\alpha$ mRNA and adipsin mRNA were observed in the experimental rats but no significantly difference on the contents. Physiologic regulated genes were not expressed In the green tea grout-fed pork meats and duck meats.

• Korean Journal of Food Science and Technology
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• v.51 no.6
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• pp.584-591
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• 2019

Of all the various types of tea that are available, Pu-erh tea has attracted much attention because of its healthpromoting effects. The objective of this study was to investigate the physicochemical and antioxidant properties of two types of Pu-erh tea, Gushu Pu-erh and typical Pu-erh, extracted at 80 and 100℃, respectively. The Gushu Pu-erh extracts showed lower pH but higher antioxidant potential at both the temperatures, as compared to the typical Pu-erh. The mineral content of the tea extracts was greater at 100℃ than at 80℃. Among the seven categories of the flavor compounds that were detected, the peak area of esters was the highest in the Gushu Pu-erh extracts. The type of tea and the extraction temperature significantly affected the physicochemical and functional properties of these tea extracts. This study revealed that Gushu Pu-erh extracted at 100℃ for 3 min with 30 s of shaking provides better results in terms of the antioxidant potential and mineral content.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.6
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• pp.745-752
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• 2005

Green tea has various medical effects. It was selected as new natural dyes guessing the effects of the biological activities are still appeared on dyeing. It was examined whether they have the function of Uv-blocker or not. Cotton, linen & Hanji were dyed with Green tea. Al, Cr, Cu, Fe and Sn were selected as the mordant and the UV blocking rate of dyed samples was measured. The results of this study as follows; 1 . The color of dyed samples with Green tea changed yellowish red except Hanji and linen mordanted with Fe. 2. K/S values of dyed samples with Green tea increased by the number of dyeing treatment(p<.01). 3. UVA and UVB blocking rate increased by the number of dyes. Cotton and Linen could block the UV radiation over $93\%$ and Hanji could block over $95\%$ after three times of dyeing. These results suggest that Hanji has possibility far various practical uses of clothing material in beautiful and functional aspect. It could have the biological effects when we put on dyed clothing material with Green tea.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.4 s.54
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• pp.311-321
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• 2005

Tea (Camellia sinenis) is a popular beverage consumed worldwide. Since green tea, mainly consumed in Asia, has various biological activities, green tea components became one of the most favorite candidates as a functional materials for cosmetics and functional foods. The biological activities of green tea for skin cue have been ranged from protection of epidermal cells to the stimulation of extracellular matrix (ECM) biosynthesis. Green tea polyphenols (GTPs), which are active ingredients of green tea, possess anti-inflammatory, anti-carcinogenic and immune potentiation properties as well as antioxidant. They also modulate intracellular signal transduction pathways. GTPs decrease ultraviolet (UV)-induced oxidative stress, thus suppress mitogen-activated protein kinase (MAPK) pathway and apoptosis in keratinocytes. In addition, GTPs prevent the Induction of inflammatory mediators, such as cyclooxygenase-2 (COX-2), interleukin-8 (IL-8), and vascular endothelial growth factor (VEGF) by tumor necrosis factor alpha $(TNF{\alpha})$ or chemical treatment in keratinocytes. GTPs treatment protects from chemical-or UV-induced skin tumor incidence in animal experiment. Besides, GTPs stimulate keratinocyte differentiation and proliferation of normal and aged epidermal cells, resectively, and suppress matrix metalloproteinases (MMPs) release. According to the progress of formulation study, green tea components will be guaranteed materials for the more effective skin cue products.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.468-471
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• 1998

Regarding the characterstics of allergic diseases, preventive and continuous treatment is desirable, and tea would be the one of the best functional food formula for it. Here we report the development of tea processing method for the leaves of Castnaea crenata. Two forms of Castnaea crenata leaf tea were prepared, non-fermented steaming tea and semi-fermented rolling tea. Anti-allergic actions of Castanea crenata leaf tea were asessed by testing their effects on the degranulation of mast cells. For this, hexosaminidase release (degranulation marker) from RBL-2H3 cells (mast cell line) was used. At the concentration of $300\;{\mu}g/mL$ of the water extract, the degranulation of RBL-2H3 cells were inhibited 50.4% and 35.4% by non-fermented steaming tea and semi-fermented rolling tea, respectively. These results suggest that the tea processing method we developed could provide a valuable resource for the treatment of allergic diseases.