• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.7
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• pp.966-976
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• 2019

Objective: The methane mitigating potential of various plant-based polyphenol sources is known, but effects of combinations have rarely been tested. The aim of the present study was to determine whether binary and 3-way combinations of such phenol sources affect ruminal fermentation less, similar or more intensively than separate applications. Methods: The extracts used were from Acacia mearnsii bark (acacia), Vitis vinifera (grape) seed, Camellia sinensis leaves (green tea), Uncaria gambir leaves (gambier), Vaccinium macrocarpon berries (cranberry), Fagopyrum esculentum seed (buckwheat), and Ginkgo biloba leaves (ginkgo). All extracts were tested using the Hohenheim gas test. This was done alone at 5% of dry matter (DM). Acacia was also combined with all other single extracts at 5% of DM each, and with two other phenol sources (all possible combinations) at 2.5%+2.5% of DM. Results: Methane formation was reduced by 7% to 9% by acacia, grape seed and green tea and, in addition, by most extract combinations with acacia. Grape seed and green tea alone and in combination with acacia also reduced methane proportion of total gas to the same degree. The extracts of buckwheat and gingko were poor in phenols and promoted ruminal fermentation. All treatments except green tea alone lowered ammonia concentration by up to 23%, and the binary combinations were more effective as acacia alone. With three extracts, linear effects were found with total gas and methane formation, while with ammonia and other traits linear effects were rare. Conclusion: The study identified methane and ammonia mitigating potential of various phenolic plant extracts and showed a number of additive and some non-linear effects of combinations of extracts. Further studies, especially in live animals, should concentrate on combinations of extracts from grape seed, green tea leaves Land acacia bark and determine the ideal dosages of such combinations for the purpose of methane mitigation.

• Natural Product Sciences
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• v.19 no.4
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• pp.281-285
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• 2013

This study was designed to investigate the nervous sedative effects of green tea. The sedative effect was evaluated by examination of Monoamine oxidases (MAOs) inhibitory activity in vitro in the brain and liver of rat fed on green tea cultivated and harvested from the different regions and periods. It showed that methanol extracts of green tea inhibited significantly the brain MAO-A activity. Especially late harvested green tea extracts showed potential inhibitory activity. The liver MAO-B activity was also inhibited by all of the green tea extracts with strong intensity. This study confirmed that major compounds of green tea such as catechin, epigallocatechin-3-gallate (EGCG) and L-theanine, which were well known for the main bioactive components in the tea plants, were not associated with the MAO inhibitory activities of green tea. These results suggested that a MAO inhibition activity comes from other minor tea components we have to search in the future.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.12-18
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• 2001

The water-soluble extracts of plants used as tea materials were investigated for their antioxidant activities and active components(total phenolics, ascorbate and selenium). Antioxidant activities of the plant extracts were determined by measuring the changes in both peroxide values(POV method) during storage(36 day, $55^{\circ}C$) and conductivity of soybean oil at $110^{\circ}C$(Rancimat method). Soybean oil without any additive was used as a control. Soybean oil treated with 0.02% BHT was used as a positive control. The test samples were prepared by mixing the plant extracts with soybean oil in 0.02% concentration by weight. The water-soluble extracts of lycii fructus(23 d), oolong tea(23 d), orange peel(23 d), citron(22 d), and apricot(22 d) showed longer induction periods, compared to control(21 d) and BHT(21 d) by POV method. Also water-soluble extracts of oolong tea(12 h), instant coffee(11 h), citron(10 h), cinnamomi cortex(10 h), schizandrae fructus(10 h), lycii fructus(10 h) and apricot(10 h) demonstrated longer induction periods, compared to control(8 h) and BHT(8 h) by Rancimat method. The contents of total phenolic compounds were observed to be high in water-soluble extracts of oolong tea, green tea, black tea, coffee, cinnamomi cortex, and cassiae semen. Ascorbate contents were found to be high in coffee, eucommiae cortex, black tea, ganoderma, cinnamomi cortex, persimmon leaf, chicory, green tea and oolong tea extracts. The selenium contents were not detected in all the extracts. The antioxidative effects of some plant extacts were seemed to be the combined effects of various antioxidant components such as phenolics and ascorbate.

• Food Science and Preservation
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• v.11 no.2
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• pp.148-153
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• 2004

The organoleptic properties of granule tea was optimized for granulation of Polygonatum sibiricum Delar(Dunggulle) tea for exclusion of scorched smell and increase of consumption. The length of 2 mm was suitable to cutting size of Dunggulle for preparation of the roasted Dunggulle. The optimum sensory conditions for aroma of Dunggulle granule tea showing 7.85 organoleptic score were 80.61% in ratio of Dunggulle extracts to total extracts, 12.77% in content of total extracts and 37.33% in rate of glucose to total sugar. The highest score of overall palatability was 5.96 at 61.11% in rate of Dunggulle extracts to total extracts, 13.79% in content of total extracts, and 60.92% in rate of glucose to total sugar.

• 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 Life Science
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• v.13 no.2
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• pp.168-174
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• 2003

The chemical compositions and antioxidant activity of green tea extracts in medilite-extraction water were compared to that of distilled water(DW). Antioxidant activity was fetermined by the formation of thiobarbituric acid reactive substances (TBARS) in rat liver homogenates and microsomes and the scavenging activity of free radicals by DPPH ($\alpha$, $\alpha$'-diphenyl-$\beta$-picrylhydrazyl). The order of total polyphenolic compounds and extracted yield by extracts was medilite 325 mesh-extraction water, medilite 600 mesh-extraction water and distilled water(DW). The ranges of scavenging activity of green tea extracts in DPPH method were 60.95% - 64.51%. The inhibition ratios of TBARS formation in the rat liver homogenates and microsomal fractions were significantly lower with green tea extracts by DW-extraction than with both medilite 325 mesh and 600 mesh-extraction water. The concentration of iron ion of water containing medilite 325 mesh and green tea extracts and of water containing medilite 600 mesh and green tea extracts were significantly higher compared to DW. Therefore, this result suggested that enhanced concentration of iron ion in green tea extracts by medilite-extraction water containing high iron ion content was associated with enhanced peroxidation of the rat liver microsomal fractions. These results showed that total polyphenolic compounds, the % of yield and mineral compounds of green tea extracts were increased using medilite 325 mesh and 600 mesh-extraction water.

• Journal of Nutrition and Health
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• v.34 no.3
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• pp.285-298
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• 2001

The effects of dried leaf powders and water and ethanol extracts of persimmon and green tea on lipid metabolism, lipid peroxidation and antioxidative enzyme activity were investigated in 12-month-old rats. Forty-nine male Sprague-Dawley rats weighing 520$\pm$19g were blocked into seven groups according to body weight. Rats were raised for four weeks with control(no tea leaf powder or extracts) and experimental diets containing either 5%(w/w) dried leaf powders of persimmon(Diospyros kaki Thunb) or green tea(Camellia sinensis O. Ktze), or water or ethanol extract from equal amounts of each dried tea powder. Food intakes of all tea diet groups were higher than that of control. Weight gains and food efficiency ratios of all tea diet groups were not significantly different from those of control. All tea diets decreased plasma triglyceride level, especially, green tea powder and persimmon ethanol diets were more effective than other diet. All the tea diet groups showed decrease in liver triglyceride level, and persimmon powder and ethanol extract increased fecal triglyceride excretion. Plasma cholesterol levels of all the tea diet groups were not significantly different from the control, but control. Fecal cholesterliver cholesterol concegroups were significantlntrations of all tea y lower than that of ol excretions of persimmon powder, green tea ethanol extract, persommon ethanol extract and green tea ethanol extract groups were significantly higher than that of control. Plasma and liver thiobarbituric acid reactive substance(TBARS) concentrations of all the tea diet groups were lower than that of control. Especially, plasma TBARS concentrations of green tea powder and persimmon ethanol extract groups were sinificantly low. Red blood cell(RBC) superoxide dismutase(SOD) activities of persimmon ethanol extract and green tea water extract groups were increased, and RBC catalase activities of all experimental groups were not significantly different. RBC glutathione peroxidase(GSH-px) activities of persimmon ethanol extract, persimmon water extract and green tea powder groups were increased. Liver SOD activities of all the tea diet groups except green tea ethanol extract group were higher than that of control. Liver catalase activities of all experimental groups were not significantly different, and liver GSH-px activity of green tea powder group was significantly higher than that of control. In conclusion, dried leaf powders, and water and ethanol extracts of persimmon and green tea were effective in lowering lipid level, inhibiting lipid peroxidation and increasing antioxdative enzyme activities in 12-month-old rat. Green tea leaf powder with high contents of flavonoids and water soluble dietar fiber was most effective in lowering plasma triglyceride, cholesterol and TBARS level. (Korean J Nutrition 34(3) : 285~298, 2001)

• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.47-52
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• 2005

This study aimed to determine inhibitory effect of pathogen growth by adding green tea extracts to some cook-chill foods. For this study, chicken meat salad and pyeonyuk were blended with green tea extracts to different concentrations of 0, 2 and $3\%$ and prepared in a cook-chill system. S. typhimurium in chickien meat salad; Better antibacterial effects of green tea extracts were observed at a $3\%$ concentration, compared with a $2\%$ concentration. Populations of S. aureus in chicken meat salad; antibacterial effects at a $3\%$ concentration became significant from 3days while that at a $2\%$ concentration remained steady throughout the five-day duration. All three testing samples exhibited a decrease in populations of S. aureus during storage. In pyeonyuk, S. aureus counts at a $3\%$ concentration were 7.26 CFU/g on day 3 and declined to 6.61 CFU/g and 6.48 CFU/g on the following days, showing a greater degree of decline than that of a $2\%$ concentration.

• 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.