• Journal of the Korean Wood Science and Technology
• /
• v.36 no.6
• /
• pp.49-58
• /
• 2008

This research was carried out to use green tea leaves powder for scavenging effects of volatile organic compounds on the UV varnishes and adhesives of fancy cherry veneer overlaid on the PF resin bonded Meranti plywood. The results are as follows: 1) Green tea leaves contained 9.85% of polyphenol compounds. 2) FT-IR results showed green tea leaves had effects to react with benzaldehyde and ethyl hexyl alcohol to form a chemical bond. 3) 2.5% of green tea leaves powder content was proper for scavenging effect on the UV varnishes and adhesives of fancy veneer overlaid on the PF resin bonded plywood 4) 20 liters small chamber test indicated excellent emission speed results such as $0.089mg/m^2hr$ of TVOC and $0.001mg/m^2hr$ of HCHO (on 7th day), as compared with standard (less than $0.1mg/m^2hr$ of TVOC and $0.015mg/m^2hr$ of HCHO emission are the excellent grade).

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

• Journal of Life Science
• /
• v.26 no.6
• /
• pp.640-645
• /
• 2016

Microglial cells are immediately activated in the central nervous system in response to a variety of neuronal environmental changes, such as injuries or inflammation. In addition to the modulation of the intrinsic immune response, a key role of microglial cells is the phagocytosis of dying cells and cellular debris. In this study, the inhibitory effects of epigallocatechine-3-gallate (EGCG), a most abundant and active polyphenol component of green tea, on lipopolysaccharide (LPS)-induced microglial activation are determined. EGCG dose dependently suppressed LPS-induced nitric oxide production and the expression of inducible nitric oxide synthase (iNOS) in BV-2 microglial cells. EGCG are potent LPS-induced inhibitors of several pro-inflammatory cytokine expressions, such as TNF-α and IL-1β, in microglial cells. Furthermore, EGCG generally inhibits the induction of LPS-mediated microglial activation and potently inhibits the phagocytosis of LPS-stimulated BV2 microglia. Although the conditioned media from LPS-stimulated BV-2 cells caused the SN4741 cell death, that from the conditioned media of EGCG pretreated BV-2 cells did not diminish the viability of SN4741 cells. These results suggest EGCG, a green tea polyphenol, could be a promising available molecule for the modulation of harmful microglial activation.

• Korean Journal of Food Science and Technology
• /
• v.24 no.4
• /
• pp.315-319
• /
• 1992

Korean green tea leaves which were harvested three times(May, June, August) were treated with anaerobic conditions and were measured changes of ${\gamma}-aminobutyric$ acid(GABA) and other constituents. In anaerobically treated green tea leaves, the content of ${\gamma}-aminobutyric$ acid(GABA) and alanine increased while glutamic acid decreased. Whereas theanine, arginine, caffeine and tannin showed little change and the content of vitamine C slightly decreased with the passing of the anaerobic treatment time. Formation of GABA, a hypotensive constituents, was proportioned to the content of glutamic acid and the optimum time of the anaerobic treatment was about 12 hours. In the anaerobic treatment of green tea leaves, effect of nitrogen gas and vacuum condition was no difference between two.

• Journal of Applied Biological Chemistry
• /
• v.55 no.2
• /
• pp.95-101
• /
• 2012

Nutritional components of Ojuk leaf tea and Ojuk shoot tea prepared from the leaves and shoots of black bamboo (Phyllostachys nigra Munro) by tea manufacturing process were evaluated. In addition, the extraction yield of water soluble components from these teas in the general tea brewing condition (water extraction in $80^{\circ}C$ for 10 min.) and the contents of polyphenol and flavonoid were compared with not only the dried raw materials, but also green tea and mate tea. Finally, offline and online scavenging activities against 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and di(phenyl)-(2,4,6 trinitrophenyl)iminoazanium free radicals were investigated to evaluate the antioxidant activity and explore the components showing ABTS free radical scavenging activity from tea infusion. These results demonstrated that these teas from black bamboo contain various nutritional components and can be used as traditional tea beneficial to human health.

• Food Science and Preservation
• /
• v.13 no.5
• /
• pp.596-602
• /
• 2006

This study was conducted to investigate the changes of major components and bioactivities of tea produce. The tea produce were made by various methods, with different degree of fermentation during manufacturing process. Except green tea, degrees of fermentation in Wizo Tea, Ilsoae Tea, and Hwang Tea were $5{\sim}10%,\;50{\sim}60%$ and $70{\sim}80%$ respectively. The result are as follows : The general component(moisture, crude ash, crude lipid, and crude protein) and the content of total polyphenol in tea products were not shown significant difference during the fermentation process. The content of caffeine in tea extracts decreased sharply as degree of fermentation of tea. In comparison of hunter values in tea extract, lightness was decreased as fermentation redness (a) was all (-), and yellowness(b) was increased sharpy with degree of fermentation. Radical scavenging activity using DPPH of tow kinds of tea was potent and decreased generally with degree of feimentation. Inhibitory effects of tea extracts against angiotensin I converting enzyme were also potent.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.2
• /
• pp.190-194
• /
• 2008

Physicochemical properties of the green tea component enriched mushroom (Flammulina velutipes) were investigated. The yield of mushroom was highest with green tea powder untreated sample and the yield was decreased by the addition of green tea powder. However, hardness was increased by the addition of green tea powder. Analysis of catechins and caffeine in mushrooms showed that catechins were not transferred into mushrooms, whereas caffeine content was increased. The content of total polyphenol in mushroom was not affected by the addition of green tea powder and crude catechins. Analyses of aroma patterns using the electronic nose based on GC with SAW sensor showed that new peaks occurred from 3 to 6 sec in green tea added mushroom. This study showed that functional components and quality of mushroom were possibly improved by incorporating green tea powder in growth medium.

• 대한치주과학회:학술대회논문집
• /
• 2004.11a
• /
• pp.153-154
• /
• 2004

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 2002.07a
• /
• pp.198-198
• /
• 2002

• Journal of Life Science
• /
• v.18 no.2
• /
• pp.273-278
• /
• 2008

Various biological resources from plants, animals, mushrooms, microorganisms, and foods were tested for the inhibitory activity against squalene synthase (SQS). Among 32 samples, more than one fourths (9 samples) exhibited significant SQS inhibitory activity. Interestingly, SQS inhibitory activity was detected in the samples such as green tea, fermented soybean paste, and plum juice. The SQS inhibitory activity of green tea was not only high but also stable. Its SQS inhibitors were supposed to be catechin derivatives, which have been known to be main bioactive components in green tea. The galloyl catechins showed higher SQS inhibitory activity compared to the nongalloyl catechins. Especially, (-)-epigallocatechin gallate appeared to be strongest inhibitor against squalene synthase ($IC_{50}=90{\mu}M$).