• 생물환경조절학회지
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• 제15권1호
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• pp.107-113
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• 2006

These studies were carried out to investigate the quality of green tea processed by different pan-firing hand rolling and to select the best conditions during the procedure of green tea processing the results were as follows. At harvestion tea plant leaf, tea plants had 4 leaves. each leaf size was 7.5 cm'$\square$2.6 cm, and weight of 100 buds 46.6 g. The increase of pan-fired time decreased in the moisture content and yield of green tea. After processing green tea, 5 times pan-fired one had much more contents of total nitrogen (T-N:5.31%), caffeine (2.00%) and total amino acid (T.A.A. : 3,046 mg%) and less content of tannin (13.41%) than the other treatments. but 3 times pan-fired one had the highest contents of vitamin C (204.3 mg%) and chlorophyll (365.0 mg%) among three kinds pan-firing method. Sixteen kinds of free amino acid including theanine as a good taste component of pan-fired green tea were isolated and measured by HPLC. Free amino acid (FAA) contents were in the range of $2,683{\sim}2,925$ mg% and among various pan-firing methods, 5 tims pan-fired one had the highest content of F.A.A. Among these free amino acids, theanine occupied as much as $56.4{\sim}61.3%$ of F.A.A. Lightness, yellowness and redness of 5 times pan-fired green tea were middle value among three different treatments. Besides, it gained the highest score of sensory evaluation among them. These above results suggested that 5 times pan-fired green tea was considered to be the best level as pan-firing times of green tea processing.

• Applied Biological Chemistry
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• 제46권1호
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• pp.23-27
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• 2003

Lipoxygenase는 녹차의 전체적인 품질에 영향을 미치는 "신선하고 풋풋한 풀 향기(green odor)" 향기특성을 가지는 $C_6-alcoho$과 $C_6-aldehyde$ 등 $C_6$화합물을 생성시키는데 관여하는 효소로서 잘 알려져 있다. 본 연구에서는 녹차잎의 초기 성장기간인 4뭘 4에서 15일까지 12일 동안에 매일 채엽한 녹차잎의 lipoxygenase 활성을 측정하고, 이에 따른 $C_6$화합물 및 terpene 등 휘발성 향기성분을 분석하여 수확 날짜에 따른 효소 활성과 녹차잎의 중요한 휘발성 향기성분의 변화를 살펴보았다. 효소활성의 측정은 linoleic acid를 기질로 한 흡광도 측정방법을 사용하였고, 휘발성 향기성분은 Solid Phase MicroExtraction (SPME) 방법으로 휘발성 향기성분을 포집한 후에 GC또는 GC-MS를 이용해 분석하였다. 실험 결과, 초기 녹차 잎 성장기간 동안 lipoxygenase 활성과 $C_6$화합물의 함량은 서로 비례하여 증가 또는 감소하였고, 이러한 변화는 당일의 온도변화와 밀접한 관계가 있는 것으로 나타났다. 즉, 온도가 증가함에 따라서 향기성분의 양도 증가하였으며, 너무 이른 시기에 채엽한 시료는 향기 성분이 매우 적은 것으로 나타났다. 본 연구로부터 "신선한 풀향기"와 "향긋한 꽃향기 (floral)" 등 녹차향 품질에 중요한 영향을 미치는 향 화합물들이 녹차의 초기 채엽기간 중에 어떻게 변화하는지에 대해서 확인 할 수 있었으며, 향기품질이 우수한 녹차를 제조하기 위해서는 생엽 성장 기간동안의 향기성분변화를 이해하는 것이 중요하다는 것을 확인하였다.

• 한국산학기술학회논문지
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• 제4권3호
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• pp.279-283
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• 2003

향신료로 널리 사용되는 마늘을 이용하여 마늘 특유의 맛과 향을 조절하여 쉽게 음용할 수 있는 tea-bag type침출차를 제조하는 방법을 개발하였다. 주재료인 마늘은 생마늘을 고온에서 구운 것보다 50℃에서 건조한 분말을 사용하는 것이 관능적으로 우수하였다. 단맛의 소재로 당전이 스테비아 감미료를 사용하여 마늘의 맛과 향을 masking할 수 있는 첨가물을 선발하였다. 그 결과 최종적으로 녹차, 둥굴레, 칡이 선발되었으며, 이들을 2종류씩 혼합한 경우 masking 효과는 두 종류의 부재료를 동량으로 사용한 실험구가 우수하였다. 마늘의 농도는 건조분말로 20∼30%, 스테비아 감미료의 농도는 1％가 적당하였다. 총 3종류의 formulation을 확립하였으며 관능적으로도 큰 차이는 없었다. 시판중인 현미녹차와 품질(색도, 탁도, 고형분 농도)을 비교한 결과 색도는 현미녹차가, 탁도와 고형분 농도는 마늘차가 우수하였다.

• 한국염색가공학회지
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• 제18권1호
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• pp.10-19
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• 2006

Despite several recent attempts to measure the concentration of individual catechins by HPLC, it has not been so easy to separate catechins accurately. The aim of the present work is to provide a proper condition for separating each component of catechins by HPLC analysis, and also to evaluate the experimental variables including color differences, and metal ion contents after dyeing and mordanting. Four kinds of Catechins, (-)-epicatechin(EC), (-)-epicatechin gallate(ECG), (-)-epigallocatechin(EgC), (-)-epigallocatechin gllate(EgCG) were isolated from the residues after dyeing. Catechins in Korean green tea leaves are richer when e tea leaves are younger. Higher concentration of catechins owes it to e way it is processed. The contents of catechins adsorbed in silk fabrics after dyeing were in order of EGCG>ECG>EGC>EC. We have found $68\%$ uptake of EGCG, and 116.8mg of EGCG in the silk fabrics after it was dyed with $1\%$ Korean green tea extracts. The absorbance intensity and K/S values of dyed silk fabrics were increased with dyeing temperature and time. Only the surface color of the silk fabric dyed with green tea extracts was yellowish red, but it changed from yellowish red to red with an increase in the mordant concentration. Post-mordanted silk fabrics with ferrous sulfate changed from yellowish red to red and purple color shade. In a practical evaluation, there is no significant change in color after twenty times of the continuous dry cleaning process. However, post-mordanted fabrics with ferrous sulfate faded the brightness of color after dry cleaning. Dyeing silk fabrics with a Korean tea extract reduced the metal ion contents in the silk fabrics when compared to the untreated silk fabrics. Metal contents in silk fabrics dyed and post-mordanted with $1\%$ each metal solution were 0.194 ppm for Aluminum, 1.601ppm for Copper, and 0.334 ppm for Iron. After the post-mordanting process, the heavy metal ion absorption increased, which was mainly attributed to the catechins and polyphenols in dyed silk fabrics.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2004년도 춘계학술발표회 논문집
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• pp.296-301
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• 2004

We focused our research interests on the characteristic of silk fabrics dyed with green tea extracts and, moreover, revealed the catechin content of silk fabrics after dyeing with Korean tea extract by measuring the residues. Three kinds of green tea samples were taken between April and May, 2003, from Bosung(southern province in South Korea), in different terms as the first corp, the second corp, and the third corp. Before and after dyeing the silk fabrics with these extracts, catechins in the residue were analyzed by HPLC. Four kinds of Catechins, such as (-)-epicatechin(EC), (-)-epicatechin gallate(ECG), (-)-epigallocatechin (EgC), (-)-epigallocatechin gallate(EgCG) were isolated from Korean green tea extracts. Catechine contents in Korean green tea leaves depend on the making process such as heating and steaming, and the younger the richer. The absorbed catechins in sillk fabrics after dyeing followed in a decreasing order of EgCG>EgC>ECG>EC. We have found a 68% uptake of EgCG, and 116.8mg/g of EgCG in the silk fabrics after dyeing with 1% Korean green tea extracts.

• 한국식품영양과학회지
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• 제12권2호
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• pp.99-104
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• 1983

1982년(年) 8월(月) 장성지방에서 수휴(收携)한 차엽(茶葉)으로 전통적(傳統的)인 볶음차(茶) 제조방법(製造方法)과 상업적(商業的) 제조방법(製造方法)에 따라 각각(各各) 녹차(綠茶)와 홍차(紅茶)를 제조(製造)하고 생엽(生葉)과 녹차(綠茶), 홍차(紅茶)의 주요성분(主要成分)인 tannin, caffeine 총(總)아미노산 유리당(遊離糖)의 함량변화(含量變化)를 측정(測定), 비교(比較), 검토(檢討)하였다. 1. 녹차생엽(綠茶生葉), 녹차(綠茶), 홍차생엽(紅茶生葉), 홍엽(紅葉)의 tannin 함량(含量)은 각각(各各) 11.79%, 12.03%, 7.89%, 3.43%로 제조후(製造後) 녹차(綠茶)에서는 2% 증가(增加)하였고, 홍차(紅茶)에서는 56.5%가 감소(減少)하였다. 2. 녹차생엽(綠茶生葉), 녹차(綠茶), 홍차생엽(紅茶生葉), 홍차(紅茶)의 caffeine 함량(含量)은 각각(各各) 2.05%, 2.58%, 1.63%, 1.58%로 제조후(製造後) 녹차(綠茶)에서는 25.9% 증가(增加)하였고, 홍차(紅茶)에서는 3.1% 감소(減少)하였다. 3. 녹차생엽(綠茶生葉), 녹차(綠茶), 홍차생엽(紅茶生葉), 홍차(紅茶) 의 총유리당(總遊離糖) 함량(含量)은 각각(各各) 115.78mg/g, 25.19mg/g, 120.72mg/g, 28.18mg/g 으로 제조후(製造後) 녹차(綠茶)와 홍차(紅茶)에서 각각(各各) 78.2%, 76.7% 감소(減少)하였다. 4. 녹차생엽(綠茶生葉), 녹차(綠茶), 홍차생엽(紅茶生葉), 홍차(紅茶)의 총(總) 아미노산 함량(含量)은 각각(各各) 279.59mg/g, 206.52mg/g, 120.54mg/g, 97.84mg/g으로 제조(製造) 후(後) 녹차(綠茶)와 홍차(紅茶)에서 각각(各各) 26.1%, 18.8% 감소(減少)하였다.

• Journal of Nutrition and Health
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• 제34권3호
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• pp.285-298
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• 2001

The effects of dried leaf powders and water and ethanol extracts of persimmon and green tea on lipid metabolism, lipid peroxidation and antioxidative enzyme activity were investigated in 12-month-old rats. Forty-nine male Sprague-Dawley rats weighing 520$\pm$19g were blocked into seven groups according to body weight. Rats were raised for four weeks with control(no tea leaf powder or extracts) and experimental diets containing either 5%(w/w) dried leaf powders of persimmon(Diospyros kaki Thunb) or green tea(Camellia sinensis O. Ktze), or water or ethanol extract from equal amounts of each dried tea powder. Food intakes of all tea diet groups were higher than that of control. Weight gains and food efficiency ratios of all tea diet groups were not significantly different from those of control. All tea diets decreased plasma triglyceride level, especially, green tea powder and persimmon ethanol diets were more effective than other diet. All the tea diet groups showed decrease in liver triglyceride level, and persimmon powder and ethanol extract increased fecal triglyceride excretion. Plasma cholesterol levels of all the tea diet groups were not significantly different from the control, but control. Fecal cholesterliver cholesterol concegroups were significantlntrations of all tea y lower than that of ol excretions of persimmon powder, green tea ethanol extract, persommon ethanol extract and green tea ethanol extract groups were significantly higher than that of control. Plasma and liver thiobarbituric acid reactive substance(TBARS) concentrations of all the tea diet groups were lower than that of control. Especially, plasma TBARS concentrations of green tea powder and persimmon ethanol extract groups were sinificantly low. Red blood cell(RBC) superoxide dismutase(SOD) activities of persimmon ethanol extract and green tea water extract groups were increased, and RBC catalase activities of all experimental groups were not significantly different. RBC glutathione peroxidase(GSH-px) activities of persimmon ethanol extract, persimmon water extract and green tea powder groups were increased. Liver SOD activities of all the tea diet groups except green tea ethanol extract group were higher than that of control. Liver catalase activities of all experimental groups were not significantly different, and liver GSH-px activity of green tea powder group was significantly higher than that of control. In conclusion, dried leaf powders, and water and ethanol extracts of persimmon and green tea were effective in lowering lipid level, inhibiting lipid peroxidation and increasing antioxdative enzyme activities in 12-month-old rat. Green tea leaf powder with high contents of flavonoids and water soluble dietar fiber was most effective in lowering plasma triglyceride, cholesterol and TBARS level. (Korean J Nutrition 34(3) : 285~298, 2001)

• Preventive Nutrition and Food Science
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• 제7권3호
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• pp.327-331
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• 2002

Tea is a pleasant, popular and safe beverage in the world. During the past decade, epidemiological studies have shown that tea catechins intake is associated with lower risk of cardiovascular disease. Tea provides a dietary source of health-promoting components to help humans reduce a wide variety of cancer risks and chronic diseases. The antioxidative activity of tea-derived catchins has been extensively studied. The antioxidant effect is a synergistic action between catechins e.g. EGCG, EGC, ECG, EC, pheophytins a and b, and other components in tea leaves, which aye more bioavailable for human body. Green tea has a Higher content of catechins than other kinds of tea. Green tea extract with hot water has high potential and more efficiency to reduce cancer risk than any other tea products or pure EGCG. Protein, iyon, and other food components may interfere with the bioavailability of ten catechins. Interaction of catechins with drug affects the cancer-preventive activity of some cancer-fighting medication. Further studies are required to determine the bioavailability of tea catechins and cancer-preventive functionality.

• 한국유기농업학회지
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• 제19권spc호
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• pp.17-20
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• 2011

Plant biomass is a huge carbon-complex that has potential as a nutrient. Therefore we extracted and separated useful materials for plant growth from tea leaf and stem. The pre-treatment process including high temperature ($200^{\circ}C$) and pressure (20-40 kgf/$cm^2$) was treated for several minutes and extracted at $120^{\circ}C$ for 30-60 minutes. After that the chemical compositions and ingredients were analyzed from that plant-nutrient. As a result of mineral contents, calcium and magnesium concentrations are higher than other minerals. Also the result of carbohydrates analyses has shown that the sugar oligomer consists of xylose(95.3%) and glucose(4.7%), and the sugar monomer consists in the order of xylose (52.7%) > manose (22.8%) > arabinose (10.8%) > galactose (10.2%) > glucose (3.5%). Before applied to field, in vitro plant growth system and formulation were examined. To evaluate the effect of the nutrients, both strawberry green-house and persimmon fields were used in this test. The treated persimmons were heavier than controls scored at 13-22%. In addition, the storage-period was extended in the treated strawberries. Interestingly in the treated strawberry, the contents of polyphenols were increased (38-57%). These results suggest that the plant-nutrient can afford to help for plant growth and storage, and it can be substituted for other commercial nutrients. In conclusion, this plant-nutrient may help to extend eco-friendly or organic farming in Hadong-gun area.

• 한국식품조리과학회지
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• 제27권5호
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• pp.567-575
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• 2011

본 연구에서는 한국 전통차(장미차, 감국차, 솔잎차, 감잎차, 뽕잎차 및 녹차)의 총 폴리페놀 및 플라보노이드 함량, 전자공여능, 아질산염 소거능 및 항균효과에 대하여 비교, 조사하였다. 장미차, 감국차, 솔잎차, 뽕잎차, 감잎차 및 녹차 추출물의 총 폴리페놀 함량은 각각 272.8, 74.6, 153.5, 73.5, 69.5 및 260.8 mg/g이었으며, 총 flavonoid 함량은 각각 75.1, 47.8, 26.8, 40.0, 27.9 및 99.5 mg/g이었다. 장미차, 감국차, 솔잎차, 뽕잎차, 감잎차 및 녹차 추출물(1 mg/mL)에 대한 전자공여능은 각각 96.8, 35.8, 71.3, 28.9, 28.8 및 95.3%이었다. pH 1.2에서의 아질산염 소거능(2 mg/mL)은 녹차(91.3%) > 장미차(49.6%) > 솔잎차(46.0%) > 감국차(15.4%) ${\qeq}$ 뽕잎차(14.2%) ${\qeq}$ 감잎차(13.5%)의 순이었다. SOD 유사활성능(5 mg/mL)은 녹차(18.7%) > 장미차(14.7%) > 뽕잎차(14.0%) > 솔잎차(11.2%) > 국화차(8.4%) ${\qeq}$ 감잎차(7.9%)의 순으로 녹차 추출물이 가장 높았으며, 국화차 및 감잎차 추출물은 거의 없었다. 장미차, 감국차, 솔잎차, 뽕잎차, 감잎차 및 녹차 추출물(5 mg/mL)의 hydroxyl radical 소거능은 각각 55.3, 64.4, 35.3, 51.5, 44.6, 29.5%이었다. 장미차의 경우 Micrococcus luteus, Bacillus cereus, Salmonella enteritidis, E. coli 모두에 대해 항균효과를 보였으며, 특히, Gram 음성균인 Salmonella enteritidis에 대해 강한 항균력을 보였다. 녹차, 솔잎의 경우 Salmonella enteritidis, Bacillus cereus에 대해 항균력을 나타내었다. 그러나 뽕잎, 감잎, 국화차의 경우는 Micrococcus luteus, Bacillus cereus, Salmonella enteritidis, E. coli 모두에 대해 항균효과를 보이지 않았다.