• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.806-811
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• 2005

Effects of green tea-soybean paste on weight-changes and serum lipid profiles in rats fed high fat diet were investigated. Sprague-Barley male rats divided into five groups were fed five different diets for 10 weeks: B group, basal diet H group, high fat-diet containing 0.5% cholesterol+15% lard H-S group, high fat diet containing soybean paste H-0.6GS group, high fat diet containing 0.6% green tea-soybean paste H-4GS group, high fat diet containing 4% green tea-soybean paste. H group showed highest weight gain (p<0.05). Addition of green-tea soybean paste to high-fat diet significantly decreased weight gain, H-4GS group showing highest weight loss (p<0.05). No significant differences in food efficiency ratio and total food intake were found among groups. Liver weight of H group was highest. Addition of green tea-soybean paste to high fat diet significantly reduced liver weight (p<0.05, Table 2). Concentrations of glucose, uric acid, bilirubin, and total protein were similar among all group. Mean GPT values of H-4GS group were significantly different from these of H- and H-S groups (p<0.05). H-S, H-0.6GS, and H-4GS groups had significantly lower triglyceride and total cholesterol, and higher HDL than H-group (p<0,05). H-4GS group had significantly lower serum triglyceride than H-0.6GS group (p<0.05).

• Archives of Pharmacal Research
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• v.25 no.5
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• pp.561-571
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• 2002

The action mechanisms of several chemopreventive agents derived from herbal medicine and edible plants have become attractive issues in cancer research. Tea is the most widely consumed beverage worldwide. Recently, the cancer chemopreventive actions of tea have been intensively investigated. It have been demonstrated that the active principles of tea were attributed to their tea polyphenols. Recently, tremendous progress has been made in elucidating the molecular mechanisms of cancer chemoprevention by tea and tea polyphenols. The suppression of various tumor biomarkers including growth factor receptor tyrosine kinases, cytokine receptor kinases, P13K, phosphatases, ras, raf, MAPK cascades, NㆍFB, IㆍB kinase, PKA, PKB, PKC, c-jun, c-fos, c-myc, cdks, cyclins, and related transducing proteins by tea polyphenols has been studied in our laboratory and others. The IㆍB kinase (IKK) activity in LPS-activated murine macrophages (RAW 264.7 cells) was found to be inhibited by various tea polyphenols including (-) epigallocatechin-3-gallate (EGCG), theaflavin (TF-1), theaflavin-3-gal-late (TF-2) and theaflavin-3,3'-digallate (TF-3). TF-3 inhibited IKK activity in activated macrophages more strongly than did the other tea polyphenols. TF-3 inhibited both IKK1 and IKK2 activity and prevented the degradation of IㆍBㆍand IㆍBㆍin activated macrophage cells. The results suggested that the inhibition of IKK activity by TF-3 and other tea polyphenols could occur by a direct effect on IKKs or on upstream events in the signal transduction pathway. TF-3 and other tea polyphenols blocked phosphorylation of IB from the cytosolic fraction, inhibited NFB activity and inhibited increases in inducible nitric oxide synthase levels in activated macrophage. TF-3 and other tea polyphenols also inhibited strongly the activities of xanthine oxidase, cyclooxygenase, EGF-receptor tyrosine kinase and protein kinase C. These results suggest that TF-3 and other tea polyphenols may exert their cancer chemoprevention through suppressing tumor promotion and inflammation by blocking signal transduction. The mechanisms of this inhibition may be due to the blockade of the mitogenic and differentiating signals through modulating EGFR function, MAPK cascades, NFkB activation as wll as c-myc, c-jun and c-fos expression.

• Food Science of Animal Resources
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• v.36 no.5
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• pp.626-634
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• 2016

This study was conducted to compare the physicochemical, microbiological and antioxidant activities of sun-dried venison amended with green tea powder (T1-3: 0, 0.5, and 1%) and Hanwoo beef jerky. Sliced beef and venison shank were marinated and sun-dried at 28-30℃ and 30-35% RH for 3.5 h. The venison jerky had a higher ash and protein content, and lower moisture and fat content than the control (p<0.05). T3 (venison+green tea powder 1%) showed a lower a_w than all other samples during storage for 10 and 20 d (p<0.05). Hunter’s color a* and b* values of T2 and T3 were lower than those of T1 and the control at day 0 (p<0.05). Saturated fatty acid was significantly higher in T1, while PUFA was higher in T2 and T3 (p<0.05). Overall sensory scores of venison jerky were lower than those of the control, except for T2, which had a similar color, flavor, saltiness and acceptability as the control. T2 and T3 showed a significant decrease in TPCs after storage for 20 d (p<0.05). The TBARS values of T3 jerky were lower than those of other jerky samples (p<0.05).

• The Plant Pathology Journal
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• v.17 no.1
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• pp.40-44
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• 2001

Disease occurrence and development of gray blight of tea (Camellia sinensis) were investigated. Higher incidences and more severe damage by gray blight were found in Japanese tea variety Yabukita than the Korean local variety. In Yabukita, Pestalotiopsis longiseta was more frequently observed on the diseased leaves than P. theae but vice versa in the Korean local variety. This indicates that there was the varietal difference in the distribution of fungal species of gray blight pathogens. Both varieties were most severely damaged during the third harvest period with weather conditions of high temperature and humidity favorable to the disease. Presence of the tea brown blight fungus Glomerella cingulata on the margin of gray blight lesion at the late stahe suggested that the pathogenic fungi of tea gray blight were replaced by the brown blight fungus during the disease development.

• Korean Journal of Poultry Science
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• v.36 no.1
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• pp.77-84
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• 2009

The objective of the study was to investigate the effects of dietary green tea on chicken meat quality and fatty acid content. Broilers were fed one of the four dietary treatments containing 0, 0.5, 1 and 3 % green tea for 10 days. Crude moisture, crude fat, crude ash, pH, meat color (CIE $L^*$, $a^*$, $b^*$) and fatty acid composition were measured in chicken breast meat during cold-storage. Crude fat did not differ significantly among treatments. Dietary green tea increased the amount of unsaturated fatty acids and decreased that of saturated fatty acids in chicken meat, resulting in increased ratios of unsaturated fatty acids to saturated fatty acids. The amount of linoleic acid (18:2) and linolenic acid (18:3) was increased with increasing dietary green tea. Lightness ($L^*$), pH, TBARS, VBN, and total plate count were not significantly different during storage. Dietary green tea did not affect storage properties of chicken meat. The results of this study imply that dietary with green tea may have positive effects on chicken meat quality.

• Preventive Nutrition and Food Science
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• v.12 no.1
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• pp.35-39
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• 2007

This study was conducted to investigate the effects of soil selenium (Se) supplementation level on Se contents of green tea and milk vetch. Four different concentrations of sodium selenite ($Na_2SeO_3$) solutions (0.0, 3.3, 33.0 and 165.0${\mu}g/mL$) were prepared and one liter of each solution was well mixed with 10 kg of compost (cowpea soil) to give four different levels of Se-containing soil: $T_1$, 0; $T_2$, 33; $T_3$, 330; $T_4$, and 1,650${\mu}g$/100 g soil. Green tea plants and milk vetch were individually cultivated in those soils for 60 days. Se contents of freeze-dried green tea leaves were 6.87, 10.40, 12.04, and 20.19 ${\mu}g/g$, respectively; all of which were significantly different (p<0.05) from the others except for $T_2$ and $T_3$. The results showed that Se-contents of green tea leaves were increased 1.5$\sim$2.9 times as the Se level in the soil increased. Regression equation between Se contents in green tea (Y) and soil Se supplementation level (X) was: Y=0.007X＋8.857. However, Se contents in the milk vetch were increased significantly (p<0.05) more with the same treatments $T_3$ (74 ${\mu}g/g$) and $T_4$ (187$\mu$g/g) in comparison to those at $T_1$ (5.0 ${\mu}g/g$) and $T_2$ (12.0$\mu$g/g). The increases ranged from approximately between 2.4 to 37.4 times that of the control group. Regression equation between Se contents in milk vetch (Y) and soil Se supplementation level (X) was: Y=0.1063X＋15.989. The large difference of Se contents between green tea leaves and milk vetch would be attributed by the difference of protein contents between the 30% or higher protein-content of legumes and 15$\sim$20% protein of shrubs. The present study clearly indicates that green tea leaves and milk vetch can be enriched in selenium by supplementing the soil with Se. Therefore, Se-enriched green tea or milk vetch powder could be utilized as functional foods in Se-fortified green tea drinks or salads, or as food additives to enhance the daily intake of Se.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.6
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• pp.634-639
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• 2004

An eight-week-old male ICR mouse, which was induced with acute alcohol and sub-acute alcohol poisoning condition, was administered with bohee tea(Camelia sinensis L) extract. After oral administration of bohee tea and inducement of acute alcohol poisoning condition, the mouses blood alcohol concentration became as low as that of the normal control group. Its decrease rate was 87.26%, in comparison with that of the positive control group. Moreover, its blood GOT activity decreased with a rate of 93.1 % until it reached the normal level, as opposed to that of the positive control group. In addition, the GOT activity, despite rising after the alcohol intake, decreased(p<0.05) significantly after administration of each sample and reached the normal level. The bohee tea group experienced a significant decrease in the GOT activity, compared with the A1codex group and the Drink group. The GPT activity of the Alcodex group decreased by 11 % compared with that of the positive control group. The CTP activity of the bohee tea group decreased by 8.2%, while that of the Drink group decreased by 6.5%(P<0.05). However, there were no significant differences between the results in the control group and those of the test group. The bohee tea group's hepatic ADH activity increased by 22.7% compared with that of the positive control group. On the other hand, the hepatic ADH activity of the Drink group increased by 33.6% while that of the A1codex group increased by 20.4%. On the contrary, the bohee tea extract, the hepatic ALDH did not manifest any significant difference as compared with the normal control group. However, its decrease rate was about 16.67% as compared with that of the positive control group. The Drink group, meanwhile, obtained a decrease rate of about 21.59%.

• Korean Journal of Poultry Science
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• v.37 no.3
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• pp.265-273
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• 2010

The objective of this study was to investigate the effects of addition of green tea extracts on physicochemical properties and shelf-life of seasoned chicken with soy sauce during cold storage. Treatments (C, T1 and T2) containing various levels (0, 1 and 2%, respectively) of green tea extracts were manufactured, and we investigated pH, meat color ($L^*,a^*,b^*$), volatile basic nitrogen (VBN), thiobarbituric acid reactive substances (TBARS), total plate counts, fatty acid composition and sensory scores during cold storage for 16 days. T1 and T2 have more dark color than control during storage time. VBN, TBARS and total plate count of control were significantly higher than those of T1 and T2 at the latter storage time (p<0.05). Also, VBN, TBARS and total plate count of all treatments was increased with storage time. Linoleic acid was the highest value in control which had the highest value of TBARS in day 16 (p<0.05). Aroma value of control was significantly higher in storage time except day 16 than those of T1 and T2 (p<0.05). Acceptability value of control was significantly higher than those of T1 and T2 in day 4, 8 and 12 (p<0.05).

• Food Science and Preservation
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• v.17 no.3
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• pp.328-333
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• 2010

The effects of green tea on the physicochemical properties of eggs were investigated. One-hundred-and-fifty Isa Brown hens (27 weeks of age) were studied over 10 weeks. Green tea was added to the diet at levels of 4% and 8% w/w. The contents of Ca, K, P, Fe and Mg in eggs increased upon dietary supplementation with green tea powder, and were higher in the yolk than in the white, with the exception of Mg. The increase was greatest for Ca, from 41.0 mg% to 119.8 mg%, in egg white. For Fe, an increase from 3.7 mg% to 12.6 mg% was apparent in egg yolk. When hens consumed the green tea-supplemented diets, average egg weight decreased from 68.8 g to 64.4 g, but the total cholesterol content of egg yolk did not significantly change (control value: 1,899.1 mg% test value: 2,011.3 mg%). In sensory evaluation tests, egg white was similar in terms of astringency and grayness regardless of diet, and egg yolk was yellow-to-orange in color, and rated as fishy or slightly fishy, when green tea diets were administered. Such diets reduced pH values in all of the white, yolk, and white/yolk combination groups. The major fatty acids of egg yolk, constituting more than 90% of total fatty acids, were palmitic, stearic, oleic, and linoleic acid. Green tea diets reduced the saturated fatty acid level from 32.0% to 27.4% of total fatty acids, and unsaturated fatty acid levels increased from 68.0% to 72.6% in egg yolk.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.85-89
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• 2005

This study was conducted to examine the effects of green tea polyphenols (GTP) and fructo-oligosaccharides (FOS) supplement on performance, counts of caecal microflora and its metabolites production. In female broiler chickens fed on semi-purified diets from 28 to 42 d of age, dietary green tea polyphenols (GTP) and fructo-oligosaccharides (FOS) significantly reduced mortality (p<0.05). Dietary GTP significantly decreased the total count of caecal microflora, each colonic population count and caecal flora metabolites contents when compared to other groups (p<0.05). Dietary FOS did not influence the total count of caecal flora but it selectively increased Bifidobacteri and Eubacteria counts (p<0.05) and decreased the count of other microflora and concentrations of caecal phenols and indole (p<0.0.5). These results suggest that GTP and FOS in semi-purified diets can decrease mortality and change the caecal colonic flora population, but GTP shows antibiotic-like effects of non-selectively decreasing all colonic flora and then metabolites, and FOS acts selectively by increasing profitable microflora and decreasing production of caecal microflora metabolites besides volatile fatty acids.