• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.807-819
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• 2012

To evaluate the functional characteristic and availability for drinking of the fermented Smilax china leaf tea by using different microbial species, various fermented leaf tea was prepared by non-fermentation (C), or the fermentation of Saccharomyces cerevisiae (S), Bacillus sp. (B), Bifidobacterium bifidus (L), Monascus pilosus (M) and Aspergilus oryzae (A), and sensory and antioxidant parameter of each brewed tea was observed. The color of the A tea was red, but the other teas were yellow in color. Furthermore, the aesthetic quality of the A and M tea was 3.95 and 3.30 point, respectively, and other teas (2.55~2.28) were similar to that of the C tea. TP of fermented tea water extract was lower than that of the C, although TF was not significantly different between the fermented and non-fermented tea. Especially, TF of the A tea was significantly lower than those of the other teas. The range of EDA ($1mg/m{\ell}$) of water and ethanol extracts of tea C and the fermented teas was 19.25~22.48%; however, tea A was only 8.04~12.49%. In addition, FRAP, FICA and LPOIA of teas were not significantly different between the fermented and non-fermented teas. On the other hand, XOIA and AOIA of tea ethanol extracts were slightly higher than those of water extracts. XOIA of water extract derived from the teas was 4.83~9.20%, while ethanol extract of these was 9.00~19.00%. However, XOIA of B and L teas water extract was not detected. Furthermore, AOIA of fermented tea water extract (30.17~48.52%) were lower than those of ethanol extract (44.09~66.93%). In this study, interestingly, antioxidant parameters, such as FRAP, FICA, LPOIA and AOIA, of the A tea water extract (0.1%) was higher than that of the other tea in spite of high decreasing rate in the contents of TP and TF. Therefore, above results imply the possibility of fermented Smilax china leaf tea as a functional food.

• Korean Journal of Food Science and Technology
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• v.24 no.1
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• pp.65-69
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• 1992

The comparative effects of ethylene oxide(EO) fumigation and gamma irradiation (5 kGy) were determined on the chemical components of exportable ginseng-leaf tea which is required for improving the hygienic quality. Saponins and fatty acids detected in the samples were found to be resistant to both treatments at the practical levels. In an experiment on free sugar and amino acids, however, quantitative analysis has shown that glucose, lysine and histidine in the samples are significantly decreased by EO fumigation (p<0.05) and that negligible changes were observed in gamma-irradiated samples.

• Journal of Food Hygiene and Safety
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• v.6 no.1
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• pp.49-56
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• 1991

Physico-chemical properties were investigated on ginseng leaf tea which was decontaminated by the current ethylene oxide fumigation and gamma irradiation, respectively. Chemical components such as soluble matter, saponin and polyphenols were found to be stable to both treatments, while ascorbic acid and chlorophylls were relatively labile to fumigation and irradiation more than 5 kGy. Instrumental analysis has shown that EO fumigation causes apparent changes in pH and color of extracts and volatile profile of the sample, as compared to negligible changes in the irradiated sample at a decontaminating dose, 5 kGy.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.10
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• pp.1595-1600
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• 2013

In the present study,effect of natural mulbelly leaf tea on DMEM MDCK cell line. Mulbelly leaf teas inhibited the proliferation in primery MDCK cells in a dose dependent manner. These results show that mulbelly teas potent inhibits the reactive oxygen species (ROS) and not destruction a component. Therefore, mulbelly teas might improve overall quality of the color and taste. And might be applied newly to development of componant mulbelly teas quality and biochemical change by ROS in living things.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.3
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• pp.313-320
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• 2017

This study was conducted to investigate the intakes and preferences related to Korean traditional teas in each of the age groups. The survey was conducted from March $9^{th}$ to $23^{rd}$, 2015. The subjects in this study were 642 adults aged more than 20 years that resided in the Seoul and Gyeonggi areas. The health status score was 3.57, and the health concern score was 3.54. The reason for preferring traditional tea was 'health' (40.5%) and 'good taste, color, and aroma' (29.7%). The most important factor in drinking a traditional tea was health (37.1%). Acceptance of each type of traditional tea was ranked in order of 'grain tea', 'fruit tea', 'floral leaf tea', 'assorted tea', 'medical root tea', and 'tonic tea'. A total of 92.8% of respondents said traditional teas should be popularized. Regarding problems for popularization of traditional teas, the most common response was 'not popularized yet' (39.7%). Regarding the method for popularization of traditional teas, the most common response was 'convenience of purchase for ingredients'. As a result, preferences for traditional tea and popularization method were different according to age. It is thus necessary to develop traditional tea products considering the age range.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.1071-1081
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• 2020

Essential oils (EOs) have been shown to be plant-extracted antimicrobial agents. However, there are limited studies investigating the efficacy of EOs against pathogens. Among them, tea tree oil (TTO) is extracted from Melaleuca alternifolia, which is also used as an antifungal agent. In this study, the effect of TTO was investigated on the suppression of melon powdery mildew caused by Podosphaera xanthii and tomato leaf mold disease caused by Passalora fulva. Both powdery mildew and leaf mold diseases were significantly suppressed by a spray of TTO. Eighty percent of powdery mildew and 81% of leaf mold disease of the control value were suppressed by 0.5% TTO liquid, when sprayed 3 times every 7 days on the melon and tomato leaves. Inhibition of mycelial growth was also greatly affected by different concentrations of TTO against four different fungal pathogens. Ninety-eight percent of Pseudocercospora fuligena, 97% of P. fulva, 95% of Botrytis cinerea, and 94% of Phytophthora infestans mycelial growth were inhibited by 0.2% to 1.0% of TTO contained in plate media, respectively. However, phytotoxicity in plants by the TTO treatments was revealed when melon and tomato leaves were sprayed with a 1% and 2% concentration of TTO, respectively. Therefore, our findings show that TTO has high antifungal effects against various plant pathogens that occur during crop cultivation. We also suggest that when applying TTO to plant leaves, it is necessary to establish an accurate treatment concentration for different crops.

• Food Science and Preservation
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• v.17 no.4
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• pp.500-506
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• 2010

This study was conducted to compare and analyze the active and general components in mate leaf tea according to degree of fermentation conditions. The contents of tannic acid of hot water extracts from #1 (mate leaf), #2 (Mate leaf after fermentation and roasting), #3 (Mate leaf after Pan-firing), and #4 (Mate leaf after final drying) were decreased according to degree of fermentation conditions. Polyphenol contents of hot water extracts were approximate in #1 and #3, with measurements of 43.45 mg/g and 38.20 mg/g, respectively. Caffeine contents were 6.78 mg/g in #1, 4.30 mg/g in #3, and 3.65 mg/g in #4. In addition, the level of total free amino acid of #1 was higher than that of #2, #3, and #4. Lightness (L) and Redness (a) values increased and yellowness (b) values decreased after fermentation. When sensory tests were conducted, mate leaf tea after fermentation had pleasant taste.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.1
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• pp.35-44
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• 2014

This study was performed to investigate the anti-photoaging effects of Persimmon leaf tea(PLT) in hairless mice(SKH-1) exposed to UVB radiation. The animals were divided into non-treated group (normal, N) and UV-radiated groups. UV-radiated groups were divided into only UV-radiated group(control, C) and UV-radiated and PLT treated experimental groups[first extraction treated group(PLT-I), second extraction treated groupe(PLT-II), and third extraction treated group(PLT-III)]. Three PLT treated experimental groups of mice were treated with both oral administration(300mg/Kg B.W./day) and topical application (100 ul of 2% conc./mouse/day) for 4 weeks. Anti-photoaging effects of Persimmon leaf were evaluated by MTT assay, anti oxidative reaction, MMP immunohistochemistry, gelatin zymography assay and RT-PCR observations. Treatment with Persimmon leaf tea(PLT)-I, and -III groups decreased immunohistochemical density of matrix metalloproteinases(MMP)-3 and -9 related to degradation of extracellular matrix in skin. Especially, immunohistochemical density of MMP-2 decreased in PLT-I, -II and -III groups in skin. On the effects of antioxidant function on the treatment with Persimmon leaf tea(PLT), treatment of HaCaT cells with extracts of PLT-I and PLT-II had also significantly reduced intracellular ROS produced by UVB irradiation in a dose dependent manner(PLT-I, p<0.05, p<0.01, p<0.001; PLT-II, p<0.01, p<0.001). Gelatin zymography assay revealed that PLT-II and PLT-III (200 ug/ml) had inhibitory effect on MMP-9 expression in UVB-radiated HaCaT cells. Western blot analysis revealed that PLT-1, -II and -III groups down-regulates the expression of inflammatory associated genes(IL-$1{\beta}$) and PLT-1 and -II groups down-regulates the expression of TNF-${\alpha}$ in a dose dependent manner. Our study suggests that Persimmon leaf tea(PLT) extracts participates in inhibitory effects on the morphological and molecular experiments related to photoaging skin on UVB irradiated hairless mice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.4
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• pp.323-327
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• 1987

The sugar contents of Dolwoe, which were prepared in the laboratory and marketed Korean products of Dolwoe, Japanese product of Dolwoe and Korean-roasted products of Dolwoe were analyzed and compared. The contents of total sugar and reducing sugar of stem in prepared Dolwoe tea were 2 times higher than those of leaf. The sugar content of Korean product was similar to that of Japanese, but the contents of total sugar and reducing sugar in Korean-roasted sample decreased to 17.2% and 40.9%, respectively. It was confirmed that free sugar in Dolwoe tea was composed of rhamnose, fructose, glucose and sucrose. The ratio of free sugar content was quite different between Dolwoe-leaf tea and Dolwoe-stem tea. Comparing the free sugar content in prepared Dolwoe tea, glucose was the highest followed by fructose, sucrose and rhamnose. On the other hand, in marketed Dolwoe tea, glucose was the highest substance and followed by fructose, rhamnose and sucrose. It was found that rhamnose content in Japanese product was approximately 6 times more than that of Korean.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.542-546
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• 2004

Changes in contents of catechins, caffeine, free amino acids, and minerals in green tea loaves according to harvest periods were compared. Total catechin content increased from 40.61 to 52.04 mg/g, while that of caffeine decreased from 17.56 to 14.61 mg/g according to harvest periods. Regardless of harvest periods, composition of catechins was epigallocatechin (EGC)>epigallocatechin gallate (EGCg)>epicatechin (EC)>gallocatechin (GC)>epicatechin gallate (ECg)>catechin (C)>gallocatechin gallate (GCg)>catechin gallate (Cg). Free amino acid content in green tea leaves was highest in young loaves, and gradually decreased according to harvest periods. Theanine content was markedly decreased with leaf aging, suggesting taste of green tea may be changed from mild to bitter with increasing harvest period. Analyses of mineral elements in green tea leaves showed that Fe, Mn, and Mg increased with leaf aging, while Cu showed opposite trend. Results reveal that content of some chemical compounds in Korean (Posong) green tea was highly dependent on harvest period.