• Food Science and Biotechnology
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• v.16 no.1
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• pp.167-170
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• 2007

(-)-Epigallocatechin-3-gallate (EGCG), a mai or tea catechin has been shown to have many interesting biological activities. In the present study, we studied the effects of green tea catechins, EGCG metabolites, and black tea theaflavins on accumulation of EGCG in HT-29 human colon cells. Intracellular levels of [$^3H$]-EGCG were not changed significantly in the presence of other tea catechins including (-)-epicatechin, (-)-epigallocatechin, and (-)-epicatechin-3-gallate. EGCG methyl metabolites and EGCG 4"-glucuronide did not affect cellular levels of [$^3H$]-EGCG. Black tea theaflavins and theasinensin A (TsA), an EGCG oxidative dimer, however, significantly decreased cellular accumulation of EGCG in HT-29 cells by 31-56%. This decrease was more pronounced when cells were incubated in the presence of theaflavin-3',3"-digallate (TFdiG) or TsA. When EGCG was added separately from TFdiG or TsA, the accumulation of EGCG in HT-29 cells was also significantly decreased regardless of when TFdiG or TsA was added during the uptake study (p<0.01). The results suggest that theaflavins and TsA may interrupt EGCG absorption through the gastrointestinal epithelium.

• The Plant Pathology Journal
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• v.37 no.1
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• pp.57-71
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• 2021

Rice sheath blight (ShB), caused by Rhizoctonia solani Kühn AG1-IA, is one of the destructive rice diseases worldwide. The aims of this study were to develop biocontrol strategies focusing on field sanitation and foliar application with a biocontrol agent for ShB management. Streptomyces padanus PMS-702 showed a great antagonistic activity against R. solani. Fungichromin produced by S. padanus PMS-702, at 3.07 mg/l inhibited 50% mycelial growth, caused leakage of cytoplasm, and inhibited the formation of infection structures of R. solani. Fungichromin could reach to 802 mg/l when S. padanus PMS-702 was cultured in MACC broth for 6 days. Addition of 0.5% S. padanus PMS-702 broth into soil decreased the survival rate of the pathogen compared to the control. Soil amended with 0.5% S. padanus broth and 0.5% tea seed pomace resulted in the death of R. solani mycelia in the infested rice straws, and the germination of sclerotia was inhibited 21 days after treatment. Greenhouse trials revealed that S. padanus cultured in soybean meal-glucose (SMGC-2) medium after mixing with different surfactants could enhance its efficacy for inhibiting the pathogen. Of six surfactants tested, the addition of 2% tea saponin was the most effective in suppressing the pathogen. S. padanus broth after being fermented in SMGC-2, mixed with 2% tea saponin, diluted 100 fold, and sprayed onto rice plants significantly reduced ShB disease severity. Thus, S. padanus PMS-702 is an effective biocontrol agent. The efficacy of S. padanus PMS-702 for disease control could be improved through formulation.

• Korean Journal of Veterinary Service
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• v.28 no.2
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• pp.91-98
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• 2005

Green tea was known which regulated adipocyte differentiation metabolism. The mechanism on the lipid decreased contents of TAG in the plasma. In addition, green tea increased the expression leptin mRNA, PPAR $\delta$ mRNA and TGF $\beta$. The tea tested was korean powdered green tea. In this experiment, Sprague-Dawley (SD) rats were fed $3\%$ green tea(powdered) for 3 weeks on the basal diet and obese diet and green tea grouts-fed pork meats. duck meats. The expression of leptin mRNA and PPAR $\delta$ mRNA were up-regulated in the green tea-fed groups compared with those of the not green tea-fed groups. There were no significantly difference on the expression of leptin mRNA and PPAR $\delta$ mRNA in green tea grouts-fed pork meats, duck meats as compared with the not fed green tea grouts meats. TGF $\beta$ mRNA. TNF $\alpha$ mRNA and adipsin mRNA were not expressed in the pork meats, duck meats. The expression of TGF $\beta$ mRNA, TNF $\alpha$ mRNA and adipsin mRNA were observed in the experimental rats but no significantly difference on the contents. Physiologic regulated genes were not expressed In the green tea grout-fed pork meats and duck meats.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.375-376
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• 2007

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.39-40
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• 2001

The inhibition of carcinogenesis by tea has been demonstrated in animal models on many organ sites. These include cancers of the skin, lung, oral cavity, esophagus, stomach, liver, small intestine, pancreas, colon, bladder, prostate, and mammary glands. The most well studied sites are skin and lung.(omitted)

• Applied Biological Chemistry
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• v.49 no.2
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• pp.163-164
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• 2006

• The Korean Journal of Pesticide Science
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• v.15 no.1
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• pp.28-35
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• 2011

The investigation of 218 residual pesticides for 19 types of tea (persimmon leaf tea, chrysanthemum tea, green tea, lavender tea, rosemary tea, dandelion leaf tea, puer tea, mulberry leaf tea, hydrangea leaf tea, jasmine tea, nuomixiang tea, buckwheat tea, mugwort tea, lotus leaf tea, oolong tea, longjing tea, rose tea, tiehkwanyin tea and huoguo tea) obtained from markets in Ansan and Suwon was carried out to assess the risk for residual pesticides in tea. The detection rate was 23.1 % (19 samples of total 65 tea samples) and the detected pesticides were 15 pesticides, such as bifenthrin, bromopropylate, chlorpyrifos, cyhalothrin, cypermethrin, chlorfenapyr, dicofol, endosulfan, fenpropathrin, fludioxonil, fenvalerate, iprobenfos, isoprothiolane, tetradifon and triazophos. The range of concentrations for the detected residual pesticides was 0.01 to 1.24 mg/kg which showed below their maximum residue limits (MRL), but the residual concentration of bifenthrin in a puer tea showed above the legal limit of 0.3 mg/kg. The result of risk assessment of residual pesticides for the detected 15 samples showed that EDI (estimated daily intake) of the pesticides detected ranged 0.0001~0.0844% of their ADI (acceptable daily intake).

• Journal of the East Asian Society of Dietary Life
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• v.16 no.4
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• pp.447-452
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• 2006

This study examined the growth and sensory characteristics of soybean sprout cultured at 25$\pm$1$^{\circ}C$ for 4 days with distilled water control and green tea extracted water (0.03% and 0.05%). The proximate composition of soybean sprout in the green-tea water was better than that of the control in ash, protein and fat, while the soybean sprout was especially higher in 0.05% green-tea water. The contents of vitamin C and $\beta$-carotene were higher in soybean sprout in green-tea water than the control. The total free amino acids composition of soybean sprout in green-tea water was better than that of the control, with the highest being obtained in soybean sprout in 0.03% green-tea water. Antioxidative activity was assayed by DPPH radical scavenging ability with spectrophotometer at 514 nm. The soybean sprout in green-tea water was higher than control. The amylase activity of the soybean sprout increased steadily during the first 4 days and that of the control was higher than soybean sprout in green-tea water. The proteinase of soybean sprout steadily increased during 4 day culture. Furthermore, the proteinase activity of soybean sprout in green-tea water was higher than that of the control up to 2 days. Whereas after 3 days, it was the highest in 0.03% green-tea water and then decreased remarkably in 0.05% green-tea water.

• Journal of the Korean Society of Food Culture
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• v.27 no.5
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• pp.512-520
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• 2012

This study investigated the sensory characteristics of adlay tea favorably consumed by Korean consumers and analyzed the drivers behind for liking or disliking adlay tea. Six adlay tea products showing the highest market share in South Korea were selected. Sensory properties of the six products were analyzed using generic descriptive analysis. Among these, four products were further selected for consumer taste acceptance test. Sensory lexicons of adlay tea were developed by trained panelists, and the sensory characteristics of each adlay tea product were measured based on the perceived intensities of these attributes elicited from the samples. In the consumer taste acceptance test, frequent tea and coffee drinkers participated. Consumers rated the acceptance of each tea product on a 9-point hedonic scale and evaluated the reasons for liking or disliking each product based on the check-all-that-apply method. Analysis of Variance, principal component analysis, frequency analysis, and correspondence analysis were utilized for statistical analysis. Twenty sensory attributes were developed in order to characterize the six adlay tea products. The results of the descriptive analysis showed that attributes such as viscosity, black soybean flavor, goso flavor, peanut flavor, seaweed flavor, green, and presence of chunks were key factors differentiating the adlay tea products. In the consumer taste test, roasted flavor, goso flavor, peanut flavor, and presence of chunks were positive drivers for liking the adlay tea products, whereas seaweed and green flavors were negative attributes that drove consumers away.

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.899-907
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• 2007

The purpose of this research was to investigate the effects of herbs, including rosemary, thyme, oregano, ginger, and green tea, on the quality characteristics and antioxidant activity of Yagkwa. After 16 days of storage at $60^{\circ}C$, all the herb-added samples showed significantly lower values for acid, TEA and peroxide than the control. The samples with rosemary and thyme showed significantly higher antioxidant activities than the other samples. The samples with rosemary and ginger showed significantly lower L-values than the control sample and the samples with thyme, oregano and green tea showed significantly lower a-values than the control. For the b-value, the control sample had the highest value. In the sensory evaluation of the Yakgwa, there were no significant differences between the samples in terms of color, flavor and texture. For overall acceptability, the rosemary-added sample showed the highest score among the samples and the thyme-added sample showed a significantly lower score than the control. In the texture analysis, all the herb-added samples, except for green tea, showed higher hardness than the control. In conclusion, the addition of herbs would be a useful way to enhance the antioxidant quality of yakgwa and rosemary would be the best choice when considering antioxidant activity and sensory characteristics.