• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.2
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• pp.148-157
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• 2005

This study was investigated to determine antimicrobial activity of the water and ethanol extracts of Korean wild green tea, semi-fermented tea, and fermented tea. Antimicrobial activity was examined against 8 kinds of several microorganisms. The minimum inhibitory concentration (MIC) of the water and ethanol extracts of green tea showed the most active antimicrobial activity against B. subtilis 0.2 mg/mL in Gram positive bacteria and P. fluorescens 0.3∼0.5 mg/mL in Gram negative bacteria. But the extracts did not show antimicrobial activity against lactic acid bacteria and yeast at the level of less than 1 mg/mL. Antimicrobial activity got lower as tea got more fermented. Antimicrobial activity of ethanol extracts from green tea, semifermented tea, and fermented tea was stronger than that of water extracts. Antimicrobial activity of the water and ethanol extracts of green tea, semi-fermented tea, and fermented tea was not destroyed at 50∼121$^{\circ}C$, and pH 3∼11, which proved to be very stable when given over heat, acid & alkali treatment. The ethanol extract of green tea, semi-fermented tea, and fermented tea was fractionated in the order of hexane, diethyl ether, ethyl acetate and water fraction. The highest antimicrobial activity was found in the water fraction, but not found in hexane fraction, while antimicrobial activity of fermented tea was not found in ether fraction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.599-606
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• 1999

Water extracts of persimmon leaf tea(PLTE), green tea(GTE) and oolong tea(OTE), at the con centration used for human consumption, were examined for inhibitory effects on the mutagenicity of major classes of dietary and environmental mutagens including indirect acting mutagens, B[ ]P (benzo[ ]pyrene), IQ(2 amino 3 methylimidazo[4,5 f]quinoline), 2 AA(2 aminoanthracene) in the presence of S9 mix and direct acting mutagen, 4 NQO(4 nitroquinoline 1 oxide) without S9 mix, using the modified Ames Salmonella/microsome assay. PLTE, GTE and OTE showed very potent and concentration dependent antimutagenic effects against indirect acting mutagens B[ ]P and IQ. At the maximum concentration(16,200 g/plate) of each tea extract, number of colonies decreased in a dose dependent manner up to 82~100%. Similar inhibition of PLTE, GTE and OTE were seen at higher concentration in the mutagenicity of the 2 AA following an initial increase in the activity at lower concentration. However, the mutagenicity of the direct acting mutagen 4 NQO were not suppressed at lower concentration of the three tea extracts, and higher concentration of the tea extracts enhanced mutagenic activity of the mutagen. There were no differences in the mode of antimutagenesis between PLTE, GTE, and OTE, in both Salmonella typhimurium TA98 and TA100 strains against the same mutagen. In conclusion, the water extracts of persimmon leaf tea, green tea and oolong tea possess marked antimutagenic potential against a variety of important dietary and environmental indirect acting mutagens, but the activity was not observed against the direct acting mutagens. These results suggest that the mode of inhibitory action may not have resulted from direct interaction between tea extracts and the mutagens, but rather from indirect metabolic inactivation of mutagens by tea extracts.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.4
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• pp.447-452
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• 2006

This study examined the growth and sensory characteristics of soybean sprout cultured at 25$\pm$1$^{\circ}C$ for 4 days with distilled water control and green tea extracted water (0.03% and 0.05%). The proximate composition of soybean sprout in the green-tea water was better than that of the control in ash, protein and fat, while the soybean sprout was especially higher in 0.05% green-tea water. The contents of vitamin C and $\beta$-carotene were higher in soybean sprout in green-tea water than the control. The total free amino acids composition of soybean sprout in green-tea water was better than that of the control, with the highest being obtained in soybean sprout in 0.03% green-tea water. Antioxidative activity was assayed by DPPH radical scavenging ability with spectrophotometer at 514 nm. The soybean sprout in green-tea water was higher than control. The amylase activity of the soybean sprout increased steadily during the first 4 days and that of the control was higher than soybean sprout in green-tea water. The proteinase of soybean sprout steadily increased during 4 day culture. Furthermore, the proteinase activity of soybean sprout in green-tea water was higher than that of the control up to 2 days. Whereas after 3 days, it was the highest in 0.03% green-tea water and then decreased remarkably in 0.05% green-tea water.

• Textile Coloration and Finishing
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• v.26 no.4
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• pp.353-362
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• 2014

This study attempted to determine the effects of fermented green tea extracts on hair by using them in a perm. For this, hair is bleached, and then the fermented green tea extracts and water were supplied to the hair using a mist sprayer. Then the hair was permed, and hair damage was tested. Regarding hair moisture levels and wave formation, specifically, the morphological changes of hair were investigated with the Scanning Electron Microscope(SEM). The study results found the following. In terms of wave formation, the fermented green tea extract-based perm was much better than the general perm. In addition, hair bleaching was more serious in the latter. According to analysis on hair moisture using SEM, hair damage was more prevalent in the general perm as well. Therefore, it was confirmed that green tea extract-based perms cause less damage to the cuticle. In other words, the potential of fermented green tea extracts as a hair cosmetics material was discovered. Furthermore, it appears that the study results contribute to the development of low-irritating scalp and hair care products using the anti-inflammatory and antimicrobial properties of the fermented green tea extracts.

• Journal of Nutrition and Health
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• v.34 no.5
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• pp.499-512
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• 2001

This study was performed to investigate effects of dried leaf powders, water, 75% and 95% ethanol extracts of persimmon leaf and green tea on lipid metabolism, lipid peroxidation and antioxidative enzyme activity in 12-month-old rats. Fifty-four male Sprague-Dawley rats weighing 542$\pm$4.5g were blocked into groups according to their body weight and were raised for four weeks with the diets containing 5%(w/w) dried leaf powders of persimmon(Diospyros kaki Thunb) and green tea(Camellia Sinensis O. Ktze), water or 75% and 95% ethanol extracts from same amount of each dried tea powder. Food intake was not significantly different among all groups, but weight gain of green tea powder group was significantly lower than that of control group. Plasma and liver lipid levels of all the tea diet groups were lower than those of control group. Especially, 75% ethanol extract of persimmon leaf decreased total lipid and triglyceride concentrations in plasma and 95% ethanol extract of persimmon leaf decreased liver total lipid level. However, there was no difference between 75% ethanol extracts groups and 95% ethanol extracts groups in lipid metabolism. Superoxide dismutase(SOD) and catalase activities in erythrocyte were remarkably increased by all the green tea diets. SOD, catalase and glutathione peroxidase activities in liver were increased by the feeding of ethanol extracts from green tea and persimmon leaf powder. Liver xanthine oxidase activity was not different among all groups. Plasma Thiobarbirutic acid reactive substance(TBARS) concentrations of all the green tea diet groups were significantly low. It was thought that high flavonoids in green tea inhibited plasma lipid peroxidation by promoting SOD, catalase activities in erythrocyte. 95% ethanol extract of persimmon leaf also inhibited plasma lipid peroxidation by high vitamin E and beta-carotene. Persimmon leaf powder decreased liver TBARS concentration by vitamin E, betacarotene and vitamin C and by increasing activities of antioxidative enzymes with flavonoids. In conclusion, dried leaf powders, water, 75% and 95% ethanol extracts of persimmon leaf and green tea were effective in lowering lipid levels and inhibiting lipid peroxidation in 12-month-old rats. Above all, ethanol extracts of persimmon leaf decreased plasma and liver lipid levels and persimmon leaf powder effectively inhibited liver lipid peroxidation. Extracts of green tea leaf inhibited plasma lipid peroxidation. In lowering lipid levels and inhibiting lipid peroxidation, ethanol extracts were more effective than water extracts, but there was no difference between 75% ethanol extracts and 95% ethanol extracts in lipid metabolism. (Korean J Nutrition 34(5) : 499~512, 2001)

• Korean journal of food and cookery science
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• v.21 no.3 s.87
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• pp.346-353
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• 2005

CThis study used HPLC to analyze the contents of 7 kinds of catechins, 4 kinds of theaflavins, and 2 kinds of methylxanthines in the following 6 kinds of commercial Korean tea: 2 green, 2 black, 1 jasmine and loolong. The following ranges in the 13 tea components of the 6 samples by ethanol extract were evaluated in mg/g: (-)-epigallocatechin, 0(black tea and jasmine tea) to 14.19(green tea); (-)-catechin 0; (+)-epicatechin, 0.62(bran rice-green tea) to 2.91(black tea); (-)-epigallocatechin gallate, 4.59(black tea) to 43.96(jasmine tea); (-)-gallocatechin gallate, 0.58(black tea) to 5.80(jasmine tea); (-)-epicatechin gallate, 5.63(bran rice-ueen tea) to 48.06(jasmine tea): (-)-catechin gallate, 0.26(black tea): theaflavif 0 to 3.66(black tea): theaflavin-3-gallate, 0 to 6.94(black tea): theaflavin-3'-gallate, 0 to 4.01(black tea); theaflavin-3,3-digallte, 0 to 10.25(black tea); caffeine, 4.60(bran rice-peen tea) to 26.44(black tea); and theobromine, 0.10(bran rice-green tea) to 1.81(jasmine tea). The contents of all components were lower by water extract than by ethanol extract. Therefore, total catechin (100.55, 45.88 mg/g) and theobromine (1.81, 0.86 mg/g) contents in jasmine tea, and theaflavin content (24.88, 1.36 mg/g) in black tea by ethanol and water extract were the highest. Caffeine content was the highest in black tea(96.48 mg/g) for the ethanol extract, and in jasmine tea (12.38 mg/g) for the water extract.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.936-941
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• 2005

Green tea was extracted with different solvents such as hot water, varying concentrations of ethanol and carbon dioxide fluid. The carbon dioxide fluid extraction of green tea was a very effective extraction method in terms of antioxidant yield and stability. At pressure of 125kgf, antioxidant extract of green tea produced a yield 1.87 and 2.8 times higher than hot water and $95\%$ ethanol extract, respectively. Antioxidant extract of carbon dioxide fluid was also very stable during 7-day storage at 35?.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.46-48
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• 2005

Growth inhibitory effects of ethanol extracts of green tea and pine needles on Bacillus stearothermophilus isolated from spoiled red bean paste were detected at concentrations higher than 750 ppm, and antimicrobial activity of pine needle extract was slightly higher than that of green tea exract. Growth inhibitory effect of pine needle extract in nutrient broth adjusted to pH 6.0, water-activity 0.92, and $45\;^{\circ}$Brix was observed at 500 ppm. These results indicated growth of B. stearothermophilus could be inhibited by adding pine needle and green tea extracts.

• Preventive Nutrition and Food Science
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• v.5 no.3
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• pp.165-169
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• 2000

Kombucha beverages were made from sweetened tea by Oriental, European and Tibetan tea fungus starters. The hot water extracts o green tea, black tea, Gugija and Omija were mixed with white and/or brown sugar, and were fermented under a static culture at 3$0^{\circ}C$. Titrable acidity, pH, color and cellulose production in kombucha beverages were evaluated. All tea fungus starters showed a higher acid production in green/black tea extracts rather than Gugija and Omija extracts. In green/black tea extracts Oriental tea fungus produced a kombucha beverage with a higher titrable acidity and lower pH than those of European and Tibetan tea fungus starters. By the static fermentation of green/black tea extract for 18 days, Oriental, Tibetan and European tea fungus starters produced cellulose pellicles of 0.43g, 0.16g, and 0.19 g (dry weight) on the top in the culture, respectively. As a mother starter, the cellulose pellicle was more efficient in acid production compared with tea fungus broth. Oriental/Tibetan mixed tea fungus showed the best acid production in the green/black tea extract supplemented with brown sugar.

• Journal of Food Hygiene and Safety
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• v.14 no.3
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• pp.238-243
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• 1999

The storage stability from powdered anchovy and its preparation cooperated with three additives (water extract from green tea and boxthorn and BHT) was studied. The results are as follows: 1. When the additives were added to powdered anchovy, the storage stability was improved. The antioxidative activities of water extract from green tea and boxthorn were considerably higher than BHT. The antioxidative activities were decreased in the rank order boxthorn > green tea> BHT. 2. The more the concentration of natural additives was increased, the more the storage stability was improved. The rank order was$60^{\circ}>40^{\circ}>20^{\circ}$ Bx. 3. The A V and POV of powdered anchovy were increased in the rank order to 6 < 12 < 18 < 24 < 30 months by storage term. 4. This clearly suggested that water extract at $20^{\circ}>$ Bx level from boxthorn was possible utilization as a new natural antioxidant for storage stability of powdered anchovy.