• Journal of the Korean Society of Food Culture
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• v.16 no.2
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• pp.170-179
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• 2001

Green Tea consists of 15-30% catechins (a type of polyphenol), which act as super antioxidants, inhibitory action against aging process. Antioxidants fight radical-free oxygen, an agent which can begin the process of cancer by damaging essential body chemicals and harming DNA. This study was peformed to develop the elderly diet using Green Tea as an inhibitory action against aging process. Nokchaborijook (Baley gruel added rice powder and Green Tea) was manufactured by various levels of Green Tea(1, 4, 7%) and the grinding period(15, 30, 45 sec). The optimum levels of added Green Tea and grinding periods on Nokchaborijook were determined with the results of sensory evaluation by response surface methodology and analysis of composition. The Anti-oxidant Vitamin A, C, E and Flavonoid were increased with increased levels of Green Tea and grinding periods be decreased. As the levels of Green Tea and grinding periods were increased, the green color and penetrated force became stronger. Among the sensory attributes, Bitterness, Green Tea Flavor and Hashness were greater depending on increasing Green Tea. Jujube flavor was greater relying on decreasing Green Tea. Greenness and spreadability of particles were increased as both the amounts of Green Tea and the grinding period were increased. This result was used to determine the optimum conditions of adding levels of Green Tea and grinding periods. The optimum conditions of Nokchaborijook was established as adding of 5.8% Green Tea grinded for 15 seconds.

• Journal of the Korean Home Economics Association
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• v.46 no.3
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• pp.49-55
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• 2008

The purpose of this study was to investigate the effects of green tea extracts (GTE) on the fermentation properties of polyphenol-enriched beers. As such, the formation patterns of tannoid in beer with GTE were investigated at 3 different infusion times, while the ale and the lager beers fortified with GTE were analyze to ascertain effects on gravity, pH, yeast viability, total polyphenol, and tannoid during fermentation period. The results were as follows: 1) The formation of tannoid in beer with GTE in the tannometer; In reaction of GTE with polyvinylpyrrolidon (PVP), control lager beer peaked in the formation of tannoid at $70\;{\sim}\;80\;mg$ of PVP, the 1st extract exceeded the detection limit, the 2nd extract at $170\;{\sim}\;180\;mg$, while the third extract at $150\;{\sim}\;160\;mg$ of PVP. The GTE were slow in reacting with PVP, and their formation patterns were different from those of polyphenols from barley and hop. 2) Ale fermentation; The final alcohol content was 9.25% (ABV). The addition of GTE increased the yeast viability after 2 days and finally reached 52.3% from 30.9%. Total polyphenol in GTE beer increased by 1.5 times (p < .05). However, its tannoid contents increased by 6.4 times. 3) Lager fermentation; The final alcohol content was 5.93% (ABV). The effect of GTE on lager beer was minimal for all variables. However, total polyphenol of GTE beer increased by 1.4 times (p < .05). Its tannoid increased by 3.3 times (p < .05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1073-1078
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• 2011

Changes of antioxidative components and activity of fermented tea manufactured by Bacillus subtilis, Saccharomyces cerevisiae, and Lactobacillus bulgaricus were evaluated during the fermentation period. The ascorbic acid content in the fermented tea was relatively lower (43.62~62.84 mg%) than that of green tea (66.74 mg%) during the entire fermentation period. The tea fermented by L. bulgaricus, which had the least contact with air, showed less change in ascorbic acid content. The polyphenol content of green tea was 14.88%, whereas that of fermented tea was 11.54~14.12% and it decreased during the fermentation period. The amount of flavonoids in green tea was 7.78 mg%, whereas that of fermented tea was 4.33~7.88 mg%. DPPH radical scavenging activity and ABTS reducing activity of green tea were 87.47% and 203.22 AEAC mg% (ascorbic acid equivalent antioxidant capacity), respectively, whereas those of fermented tea were lower than green tea. Results indicated that the antioxidative components and activity of fermented tea were lower than those of green tea during the fermentation period. But, when the sensory and hygienic quality are considered, fermented tea can be one of the higher quality tea products on the market.

• Applied Biological Chemistry
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• v.50 no.3
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• pp.210-216
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• 2007

Cosmetic products including skin and essence were manufactured to analyze the effect of green tea polyphenols addition. In addition, irradiation was applied to remove an undesirable color of green tea polyphenol(GTP), which may cause a problem in the marketing, of a final product; moreover, comparative studies were conducted with the cosmetic products on whether or not antiseptics were treated to verify its use for the development of non-antiseptic cosmetic products. Growth inhibition zones were shown in the microbial study except for Candida albicans. The minimum inhibitory concentration(MIC) of E. coli and C. albicans was 2,500 ppm but that of S. aureus was 1,000 ppm. The numbers of E. coli and S. aureus were reduced to undetected levels when 10,000 and 5,000 ppm of polyphenol were added, respectively. Results indicate that the addition of irradiated green tea polyphenol provides a good method to manufacture functional cosmetics including skin and essence with various biological activities such as antimicrobial activity without antiseptics.

• Preventive Nutrition and Food Science
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• v.7 no.3
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• pp.327-331
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• 2002

Tea is a pleasant, popular and safe beverage in the world. During the past decade, epidemiological studies have shown that tea catechins intake is associated with lower risk of cardiovascular disease. Tea provides a dietary source of health-promoting components to help humans reduce a wide variety of cancer risks and chronic diseases. The antioxidative activity of tea-derived catchins has been extensively studied. The antioxidant effect is a synergistic action between catechins e.g. EGCG, EGC, ECG, EC, pheophytins a and b, and other components in tea leaves, which aye more bioavailable for human body. Green tea has a Higher content of catechins than other kinds of tea. Green tea extract with hot water has high potential and more efficiency to reduce cancer risk than any other tea products or pure EGCG. Protein, iyon, and other food components may interfere with the bioavailability of ten catechins. Interaction of catechins with drug affects the cancer-preventive activity of some cancer-fighting medication. Further studies are required to determine the bioavailability of tea catechins and cancer-preventive functionality.

• Journal of Applied Biological Chemistry
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• v.55 no.1
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• pp.19-25
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• 2012

Green tea leaves were fermented for 15 and 30 days with Monascus pilosus which is known to produce functional statins (TMs), and the content of various biochemical constituents such as total polyphenol (TP), total flavonoid (TF), theaflavin, and thearubigin were analyzed and compared with that of non-fermented green tea (GT) and Pu-erh Chinese post-fermented tea (PU). In addition to the electron donating ability (EDA), ferric iron reducing power (FIRP), xanthine oxidase (XO) inhibitory activity, superoxide dismutase (SOD)-like activity, iron chelating activity (ICA) and hydrogen peroxide contents were also measured and compared with that of GT and PU. Content of TP and TF in the water and ethanol extracts in TMs were lower than those in GT and PU. Theaflavin and thearubigin contents of water and ethanol extracts in TMs were higher than those of GT. And, these components were increased depending on the period of fermentation. While, EDA and FIRP of TMs were lower than those of GT, XO inhibitory activity of TMs was higher than non-fermented tea. While, ICA of TMs was slightly higher than GT and PU, the content of hydrogen peroxide in TMs was markedly lower than GT. This results suggested that the green tea fermented by M. pilosus was valuable for oxidative stress-induced diseases by decreasing hydrogen peroxide, and forming theaflavins and thearubigins with functionality of genus Monascus.

• KSBB Journal
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• v.23 no.5
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• pp.387-391
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• 2008

Green tea is popular plants in Asian countries and has become more widespread in western countries due to its taste characteristics and health benefits. Apart from green tea leafs, however, the use of root and seed of green tea tree has not intensively been investigated yet. In this study, the contents of mineral, vitamin, total amino acid, free amino acid, and total polyphenol (catechin, caffeic acid, and chlorogenic acid) of the root and seed of green tea tree were analyzed for the development of healthy foods. For minerals, potassium contents were 1,052 and 1,480 mg/100g-dry weight of root and seed, respectively. The order of mineral contents were as follows: K > P > Ca > Mg > Na > Fe > Mn > Zn > Cu in root and K > P > Na > Ca > Mg > Mn > Fe > Cu > Zn in seed. For vitamins, vitamin C contents were 5.72 and 6.05 mg/100g-dry weight of root and seed, respectively. The presence of more various kinds of vitamins were observed in seed than in root. For total amino acids, the contents were 1,651 and 4,335 mg/100g-dry weight of root and seed, respectively. The total amino acid contents of seed and root were higher than those in commercial green tea products. Especially the phenylalanine contents were 16 and 139 mg/100g-dry weight of root and seed, respectively whereas phenylalanine was not found in commercial green tea products. Concerning free amino acids, the bitter tasting amino acids such as arginine, valine and tryptophan were more abundant in root and the sweet tasting ones such as glutamic acid, alanine, aspartic acid, and serine were more abundant in seed. The total polyphenol contents were 237 and 81 mg/100g-dry weight of root and seed, respectively. The polyphenol contents in root were three times higher than that in seed so root may be a better source for antioxidant ingredients than seed. Among many polyphenols, catechin, caffeic acid, and chlorogenic acid were the top three major components.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.2
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• pp.183-189
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• 2014

We investigated noodles supplemented with functional ingredients for their antioxidant properties, including total phenol, flavonoid contents, electron donating, nitrite scavenging abilities and ferrous ion chelating effect. The total polyphenol contents of functional noodles arranged in order of decreasing concentration were kudzu (7.98%) > green tea (4.99%) > pumpkin (5.03%) > mulberry leaves (4.99%) > mugwort (4.23%) > cactus (3.57%) > kelp (3.33). The total flavonoid contents in green tea noodles were the highest as 4.35%. The electron donating ability in mugwort noodle was the highest as 12.27% at 1,000 ppm. This amount was 4.85 times than that of wheat flour noodle (2.53%). The nitrite scavenging ability of functional noodles at pH 1.2 arranged in order of decreasing concentration were green tea (66.52%) > cactus (55.12%) > kudzu (52.67%) > pumpkin (50.50%) > mulberry leaves (43.58%) > kelp (41.41%) > mugwort (37.66). The nitrite-scavenging ability of green tea noodle was lower than ascorbic acid (natural antioxidant) 77.83%, while that of green tea noodle was similar with BHT (artificial antioxidant) 69.45%. The ferrous ion chelating effect of noodles containing kelp were the highest as 27.02%. All of the experimental results showed good antioxidant property. Thus, noodles supplemented with mulberry leaves, cactus, mugwort, green tea, pumpkin, kelp or kudzu, demonstrated to have good functional effects for human health.

• The Korean Journal of Food And Nutrition
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• v.18 no.3
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• pp.219-224
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• 2005

To see the antioxidative ability of puer tea against green tea, antioxidative effects of water and methanol extracts were compared and researched each. Water extracts from green tea and puer tea contain similar percentage of total polyphenol content while methanol extract from puer tea has about $58\%$ of total polyphenol content of that from green tea. Water extracts from both teas contain similar percentage of the electron donating ability while methanol extract from puer tea has about $54\%$ of the electron donating ability of that from green tea. Solvents made a big difference in SOD-like activities. The activations in water extracts were from $13.46\%$ to $48.93\%$, which didn't give much difference between green tea and puer tea. However, the activations in methanol extracts were $59.63\%$ in green tea and $48.93\%$ in puer tea, which was $3\~4$ times higher than that in water extracts and green tea activated better. The nitrite scavenging activity was similar in water extracts from both teas and the methanol extract from puer tea had a bit higher nitrite scavenging activity than that from green tea. The ACE inhibitory activity in water extract from puer tea was about $38\%$ higher than that from green tea while the activity of methanol extract from green tea was higher than that from puer tea. These results indicate that the antioxidative ability of water extract from puer tea is similar to that from green tea but the ACE inhibitory activity of puer tea reveals higher value and antioxidative ability of methanol extract from puer tea was lower than that from green tea while the nitrite scavenging activity of puer tea was higher.

• Textile Coloration and Finishing
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• v.20 no.5
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• pp.7-13
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• 2008

In order to introduce new functions onto textile fabrics, nylon and cotton were treated with green tea extracts. And then the anti-oxidant activity of fabrics treated with the extracts was evaluated by Blois method using DPPH ($\alpha$, $\alpha$-diphenyl- $\beta$-picrylhydrazyl). The anti-oxidant activity was exhibited on the textile fabrics treated as well as by the extracts itself. The cotton fabric treated with 10% o.w.f. of extract appeared to have almost 90% of anti-oxidant activity and 95% was obtained for nylon.