• Korean Journal of Food Science and Technology
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• v.53 no.4
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• pp.454-462
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• 2021

This study investigated the antioxidant and nitric oxide (NO) inhibition effects of three domestic and seven foreign fermented black tea 70% ethanol extracts. Bosung showed the highest total polyphenol and tannin contents. Jeju showed the highest total flavonoid contents. The theanine content was higher in Hadong (651.50 mg%) than in foreign fermented black tea. At 25 ㎍/mL, the domestic fermented black tea extract showed the highest DPPH and ABTS racial-scavenging activities, reducing power assays. Domestic fermented black tea showed higher NO inhibitor activity than foreign black tea at 50 ㎍/mL. Bosung black tea extract showed an increase in SOD-1 level (1.39-fold) compared to the LPS-only group. Bosung and Jeju decreased the GST protein by 1.52- and 1.46-folds, respectively, compared to the LPS-only group. Thus our results suggest that domestic fermented black tea (Bosung, Jeju, and Hadong) are effective antioxidants in RAW 264.7 cells.

• Journal of Life Science
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• v.21 no.2
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• pp.322-327
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• 2011

The effects of green tea consumption and/or exercise for 12weeks on body weight and select biochemical markers in plasma were evaluated in obese adolescents with a fat ratio of greater than 25%. The subjects were randomly divided into a control group (n=9), green tea consumption group (n=9), exercise group (n=9) and green tea consumption with exercise group (n=9). Subjects in both green tea consumption group and green tea consumption with exercise group were given more than five cups of green tea extract in hot water ($90^{\circ}C$) daily, equivalent to 1.5-1.7 g dry green tea, for 12 weeks. Subjects in both the exercise group and green tea consumption with exercise group participated in a training program (HRmax 60-70%, 60 min/day) for 12 weeks. Control subjects were only given water equal to the quantity of green tea being given to the subjects of green tea consumption. No significant changes body weights were seen in any of these treatments, but the waist to hip ratio was reduced with treatments of both green tea and exercise. The control group showed no significant changes in TNF-$\alpha$, IL-6 and leptin levels. Green tea consumption reduced leptin (p<0.05), TNF-$\alpha$, and leptin levels. Exercise lowered TNF-$\alpha$ (p<0.05), IL-6 (p<0.01), and leptin (p<0.05) concentrations. Meanwhile, a combination of green tea consumption and exercise lowered TNF-$\alpha$, IL-6 (p<0.05) and leptin (p<0.05) levels. These results indicate that green tea consumption and exercise both had a positive effect on the reduction of inflammatory cytokines, TNF-$\alpha$, IL-6 and leptin, in obese adolescents, but no synergistic effect on the reduction of these cytokines.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.106-113
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• 2015

Effects of mineral salts (N, P, K, $Ca^{2+}$, $Mg^{2+}$, and $Fe^{3+}$) on the shoot growth and metabolite production of tea tree were studied using in vitro culture techniques. Among mineral s alts, ${H_2PO_4}^-$ was the most important for enhanced growth rate of tea tree, while $Mg^{2+}$ and $Ca^{2+}$ did not affect plant growth. Removal of ${NH_4}^+$ and $NO_3$ from the culture medium enhanced shoot multiplication compared to other treatments. Metabolite production was variable depending on mineral types and concentration. Removal of $Ca^{2+}$ decreased the production of caffeine; however, other treatments did not influence its production. $Ca^{2+}$, ${NH_4}^+$ and $Fe^{3+}$ were important factors for catechin production in tea tree. These results can be used as the basis for development of technical soil controls suitable for tea tree cultivation in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.2
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• pp.140-148
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• 2018

As the global warming causing desertification increase, there is growing concern about damage of crops. It was to investigate how the treatment with hydrogen peroxide before leaf development affects the growth and yield of sorghum for minimizing a damage of crops to drought. The germination experiment was conducted at alternating temperature of $25^{\circ}C/20^{\circ}C$(12 hr/12 hr) under water stress condition of 0 ~ -0.20 MPa adjusted with PEG solution containing 0 and 10 mM $H_2O_2$. In order to know the effect of foliar application of hydrogen peroxide on the growth of sorghum, 10 mM hydrogen peroxide was treated to leaves at 3-leaf stage of sorghum growing in greenhouse conditions. Seed germination rate was increased by 20% in hydrogen peroxide treatment as compared to the Control. under water stress conditions (-0.15 ~ -0.20 MPa). The length of seedlings was also on the rise by the hydrogen peroxide treatment. In the greenhouse pot experiment, the morphological characteristics (plant height, stem diameter, leaf length, and leaf number) and physiological characteristics (chlorophyll content, chlorophyll fluorescence (Fv/Fm), stomatal conductance) were higher in the plants treated with hydrogen peroxide under the drought stress condition than those of plants of $H_2O$ treatment. Experiment conducted with the soil moisture gradient system showed that the foliar application of hydrogen peroxide increased photosynthetic ability of sorghum plant with respect to SPAD value and stomatal conductance and rooting capacity (root weight and root length) under drought condition. Generally, hydrogen peroxide treatment in sorghum increased the tolerance to drought stress and maintained better growth due to ameliorating oxidative stress.

• Journal of agriculture & life science
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• v.45 no.5
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• pp.1-8
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• 2011

In this study, 160 tea tree (Camellia sinensis L.) lines were classified by caffeine content using colorimetric methods. Among them, caffeine-rich lines (HR-78, HR-137, HR-82 and HR-123) and poor lines (HP-85, HP-88, HP-19, and HP-131) were selected. To know the difference in morphological and genetic characters between caffeine-rich and poor lines, we used leaf/shoot growth and RAPD methods. Cluster pattern of morphological characters (leaf width, leaf length, leaf area and shoot length) showed that shoot length was longer in caffein-rich lines than in -poor lines. In genetic analysis, amplified DNA bands having various sizes were detected in RAPD analysis where 30 random primers were used. However, the discriminated primer set that distinguish caffein-rich tree line from -poor lines was not found. These results can be used as the basic data to determine the morphological and genetic differences among caffein-rich and -poor lines.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.41-46
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• 2011

In this study, in addition to the green tea-wood fiber hybrid composite boards of previous researches, to make effective use of saw dust of domestic cypress tree with functionalities and application as interior materials, eco-friendly hybrid composite boards were manufactured from wood fiber, green tea and saw dust of cypress tree. We investigated the effect of the component ratio of saw dust and green tea on static bending strength performances. Static bending MOE (modulus of elasticity) was within 0.956~1.18GPa, and showed the highest value in wood fiber : green tea : saw dust = 50 : 40 : 10 of the component ratio, and had the lowest value in 50 : 30 : 20 of component ratio. These values were 2.0~3.1times lower than those of green tea-wood fiber hybrid composite boards reported in the previous researches. The bending MOR (modulus of rupture) showed 8.99~11.5MPa, the change of the bending MOR with component ratio of the factors was the same as that of bending MOE. These values had 1.9~3.5 times lower value than those of green tea-wood fiber hybrid composite boards, and showed the slightly lower values than the MOR of particle boards (PB) and medium density fiberboards (MDF) prescribed in Korean Industrial Standard. Therefore, it is considered that these hybrid composite boards need to improve strength performances by component ratio change, hybrid composite with other materials and adhesive change etc. in order to industrialize the hybrid composite boards.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.267-277
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• 2021

To evaluate hepatoprotective effects, the antioxidant capacities of matcha green tea extract (Camellia sinenesis) were compared to those of green leaf tea and the anti-inflammatory activities in HepG2 cells were investigated. Evaluation of the total phenolic and total flavonoid content, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and inhibitory effect on lipid peroxidation indicated that the aqueous extract of matcha green tea presented significant catechin content and antioxidant capacity compared to those of green leaf tea. In addition, the extract had considerable inhibitory effects on α-glucosidase, α-amylase, and advanced glycation end-products. The matcha green tea extract significantly increased cell viability and reduced reactive oxygen species in H₂O₂- and high-glucose-treated HepG2 cells. Furthermore, in response to oleic acid-induced HepG2 cell injury, treatment with matcha green tea aqueous extract inhibited lipid accumulation and regulated the expression of inflammatory proteins such as p-JNK, p-Akt, p-GSK-3β, caspase-3, COX-2, iNOS, and TNF-α. Matcha green tea could be used as a functional material to ameliorate hepatic lipid accumulation and inflammation.

• Korean Journal of Medicinal Crop Science
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• v.5 no.3
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• pp.217-224
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• 1997

The significant chemical components estimating the quality of green tea were compared and analyzed in the shoots of Korean native tea plants. The results are summarized as follows. The contents of total nitrogen in tea leaves were in range of $3.59{\sim}4.89%$, and the tea plants grown wildly in Bosong Daewonsa, Hwasun Ssangbongsa, Shunchun Changchun-ri, Hadong Ssanggyesa. and the cultivated tea plants in Kangjin Jangwon Sanup had higher contents of total nitrogen. The contents of tannin ranged from 12.5 to 18.3%. The contents of tannin of Kuryoi Chonunsa (18.3%), Kangjin Baekryonsa (16.7%) and Naju Bulhoisa (16.4%) were higher than those of Yangkwang Chonma-ri (12.5%), Hampyong Yongam-ri (12.7%) and Yosu Udu-ri (12.8%). The contents of caffeine were in range of $2.21{\sim}3.11%$. The contents of caffeine of Kwangju Shamae Dawon (3.11%), Kangjin Jangwon Sanup (2.94%) and Shunchun Changchun-ri(2.87%) were higher than those of Tamyang Yanggak-ri(2.21%), Yosu Udu-ri(2.23%) and Kuryoi Hwaomsa (2.23%). The contents of vit. C were in range of $167.9{\sim}223.5mg/100g$. The contents of vit. C of Changsong Oshan-ri (167.9mg/100g), Shunchun Shongkwangsa (185.6mg/100g) and Yongkwang Chonma-ri (185.8mg/100g) were lower than those of Kwangju Shamae Dawon (291.5mg/100g), Kangjin Jangwon Sanup (271.8mg/100g) and Shunchun Changchun-ri (269.5mg/100g). The contents of chlorophyll were in range of $187.4{\sim}332.7mg/100g$, and the mean contents were in range of 242.0mg/100g. The contents of total amino acids were in range of $1,888{\sim}2,500mg/100g$. The content of total amino acid at Kangjin Jangwon Sanup was the highest as 2,500mg/100g, and that of Shunchon Shongkwangsa was the lowest as 1,888mg/100g. Results of this study suggest that the native tea plants naturally grown at Bosong Daewonsa, Hwasun Ssangbongsa, Shunchun Changchun-ri, Hadong Ssanggyesa, and the cultivated tea plants at Kangjin Jangwon Sanup show excellent quality in terms of abundance of total nitrogen and total amino acids, and less contents of tannin.

• Journal of agriculture & life science
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• v.46 no.2
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• pp.9-17
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• 2012

In this study, in addition to the green tea - wood fiber hybrid composite boards of previous researches, to make effective use of saw dust of domestic cypress tree with functionalities and application as interior materials, eco-friendly hybrid composite boards were manufactured from wood fiber, green tea and saw dust of cypress tree. We investigated the effect of the component ratio of saw dust and green tea on dynamic MOE (modulus of elasticity). Dynamic MOE was within 1.41~1.65 GPa, and showed the highest value in wood fiber : green tea : saw dust = 50 : 40 : 10 of the component ratio, and had the lowest value in 50 : 30 : 20 of component ratio. These values were 1.4~1.6 times higher than static bending MOE of wood fiber - saw dust - green tea hybrid composite boards, and were 2.0~2.9 times lower than those of green tea - wood fiber hybrid composite boards reported in the previous researches. From the results of correlation regression analyses between dynamic MOE and static strength performances, a very high correlation coefficients were obtained, therefore it was found that static bending strength performances can be estimated with a high reliability from dynamic MOE.

• Food Engineering Progress
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• v.21 no.2
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• pp.158-166
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• 2017

Although Semisulcospira libertina is generally regarded as a supplement for the alleviation of alcohol hangover, little is known about its effects on cell metabolism. Therefore, this study was conducted to analyze the constituents of the extracts prepared using different extraction methods and to compare their biochemical properties. The amino acid contents were found to be much higher in acidic and enzymatic hydrolysates than hot water extracts from S. libertina. DPPH radical scavenging activities in acidic and enzymatic hydrolysates were higher than those of hot water extracts. Three types of S. libertina hydrolysate was added to HepG2 cells damaged by acetaminophen (AAP), after which the survival rate of HepG2 cell were measured. In addition, lactate dehydrogenase (LDH) activities in the culture media were evaluated. The survival rates of HepG2 cells were $77.0{\pm}4.3%$ and $81.5{\pm}1.3%$ at 3 h and 5h enzymatic hydrolysates, respectively. These cell survival rates were higher compared to those of the negative control group ($67.8{\pm}4.3%$) treated only with acetaminophen. Cellular toxicities induced by treatment with AAP were also significantly alleviated in response to treatment with the extracts of S. libertina. In addition, the activities of 2 key enzymes that metabolize ethanol, alcohol dehydrogenase and aldehyde dehydrogenase, were upregulated by 4.7- and 2.7-fold respectively in response to treatment with a 3 h enzymatic hydrolysate of S. libertina. Taken together, these results provide biochemical evidence of the method by which S. libertina exerts its biological functions, including the alleviation of alcohol hangover and the protection of liver cells against toxic insults.