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Gyeonggi, South Korea

Hong Y.-H.,Korea Food Research Institute | Jung E.Y.,Korea Food Research Institute | Park Y.,Korea Food Research Institute | Shin K.-S.,Kyonggi University | And 4 more authors.
Bioscience, Biotechnology and Biochemistry

This study describes increases in extraction efficiency and the bioconversion of catechins after treatment with several commercial enzymes. Tannase was also used to improve the anti-radical activities of green tea extracts. Enzymatic treatment with various commercial enzymes was introduced to improve the extraction efficiency of polyphenols. The total polyphenol, flavonoid, and catechin contents and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of the green tea extract treated with Viscozyme (VG) were significantly higher than those treated with other commercial enzymatic extractions (p < 0:05). More than 95% of the epigallocatechingallate (EGCG) and of the epicatechingallate (ECG) was hydrolyzed to epigallocatechin (EGC) and to epicatechin (EC) in successive 20 min treatments with Viscozyme and tannase (TG). Due to its hydrolytic activity, treatment involving tannase resulted in a significant release of gallic acid (GA), EGC, and EC, leading to greater radical scavenging activities. Regarding the IC50 values of the DPPH and 2,2-azino-di-(3- ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals, the green tea extract treated with TG showed values of 131.23 and 28.83μg/mL, VG showed values of 224.70 and 32.54μg/mL, and normal green tea extract (NG) showed values of 241.11 and 66.27μg/mL, respectively. These results indicate that successive treatment with Viscozyme and tannase improves the extraction efficiency of polyphenols and increases radical scavenging activities. Source

Hong Y.-H.,University Institute of Health Sciences | Jung E.Y.,Korea University | Shin K.-S.,Kyonggi University | Kim T.Y.,Bionic Trading Corporation | And 3 more authors.
Applied Biochemistry and Biotechnology

Ultraviolet B (UVB) irradiation may induce the acceleration of skin aging. The purpose of this study was to develop an effective formulation containing tannase-converted green tea extract (FTGE) to inhibit UVB-induced oxidative damage. Significant (p∈<∈0.05) prevention of the reduced form of glutathione (GSH) depletion was observed in mice treated with FTGE. The hydrogen peroxide levels of mice treated with FTGE were similar to those of UVB non-irradiated mice. No significant difference was observed between No UVB control and FTGE mice. Also, mice treated with FTGE had significant (p∈<∈0.05) decreases in thiobarbituric acid-reactive substance levels by lipid peroxidation compared with No UVB control mice. Our data suggest that this formulation may be effective in protecting skin from UVB photodamage. © 2011 Springer Science+Business Media, LLC. Source

Hong Y.-H.,Korea University | Yeon Y.K.,Korean University of Science and Technology | Jung E.Y.,Korea University | Shin K.-S.,Kyonggi University | And 3 more authors.
Journal of the Korean Society of Food Science and Nutrition

In this study, we optimized the reaction conditions for the bioconversion of green tea using tannase, and to evaluate its radical scavenging activities. Tea catechins such as (-)-epigallocatechin gallate (EGCG) or (-)-epicatechin gallate (ECG) were hydrolyzed by tannase to produce (-)-epigallocatechin (EGC) or (-)-epicatechin (EC), respectively, and a common product, gallic acid. The bioconversion of tea catechins by tannase was increased as enzyme concentration, substrate concentration and incubation time for enzyme dose. The results indicated the optimum reaction conditions for tannase were tannase 30 U/mL (enzyme concentration) on 1% green tea (substrate concentration) for 1 hr (incubation time for enzyme). Tannase enhanced the radical-scavenging properties of green tea; the 2,2-azinobis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals scavenging abilities were significantly (p<0.001) greater for the tannase-treated green tea extract compared to the untreated green tea extract. It is reported that ECG has the greatest antioxidant activity among the catechins in green tea, and the release of gallic acid is considered to be beneficial because of its significant antioxidant potency. The results of this study suggest that the tannase-treated green tea increases antioxidant activities under optimum reaction conditions. Source

Park H.-R.,Kyonggi University | Park H.-R.,Korea University | Suh H.J.,Korea University | Yu K.-W.,Korea University | And 2 more authors.
Journal of the Korean Society of Food Science and Nutrition

In order to develop new immuno-stimulating ingredients from mature leaves of green tea, crude polysaccharides were isolated from pectinase digests of tea leaves (green tea enzyme digestion, GTE-0), after which their immuno-stimulating activities and chemical properties were examined. GTE-0 mainly contained neutral sugars (54.9%) such as glucose (14.2%), arabinose (12.2%), rhamnose (11.1%), and galacturonic acid (45.1%), which are characteristic of pectic polysaccharides. The anti-complementary activity of GTE-0 was similar to that of polysaccharide K (used as positive control). Number of morphologically activated macrophages was significantly increased in the GTE-0-treated group. GTE-0 significantly augmented H2O2 and reactive oxygen species production by murine peritoneal macrophage cells in a dose-dependent manner, whereas production of nitric oxide showed the highest activity at a dose of 100 μg/mL among all tested concentrations. Murine peritoneal macrophages stimulated with GTE-0 showed enhanced production of various cytokines such as interleukin (IL)-6, IL-12, and tumor necrosis factors-α in a dose-dependent manner. Further, GTE-0 induced higher phagocytic activity in a dose-dependent manner. In ex vivo assay for cytolytic activity of murine peritoneal macrophages, GTE-0-treated group showed significantly higher activity compared to the untreated group at an effector-to-target cell ratio of 20. The above results lead us to conclude that polysaccharides from leaves of green tea have a potent immuno-stimulating effect on murine peritoneal macrophage cells. © 2015, J Korean Soc Food Sci Nutr. All right reserved. Source


Bionic Trading Corporation | Date: 2013-12-09

Theanine for pharmaceutical purposes for use in the treatment of anxiety, high blood pressure, and preventing Alzheimers disease, and L-Theanine for pharmaceutical purposes treatment of anxiety, relieve stress by inducing a relaxing effect without drowsiness, high blood pressure, and preventing Alzheimers disease. Dietary food supplements or dietary and nutritional supplements, namely, containing fermented red ginseng, fermented red ginseng liquid, fermented red ginseng powder, or ginseng powder; containing gynostemma pentaphyllum extract, containing Omega-3 fatty acids; containing starch extract in the nature of cyclodextrin; containing chitosan, containing lucosamine from crustacean, containing edible sunflower oil, edible linseed oil, edible evening primrose oil, edible olive oil, edible grape seed oil, edible rice kernel oil, or hovenia dulcis extract; containing black garlic, black soybean, mandarin, cabbage, or mugwort; and containing processed meats in the nature of horse placental extract and yam extract in the nature of octacosanol.

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