• 생명과학회지
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• 제6권2호
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• pp.104-110
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• 1996

The present study was conducted to elucidate the functional property of tea extract obtained from tea extracts, semi-fermented tea(oolong tea) and fermented tea(black tea). Tea extracts exhibited remarkable nitrite-scavenging actions, and the action increased with the increased of the amount of tea extracts. The nitrite-scavenging actionof tea extracts showed pH dependent, highest at pH 1.2 and lowest at pH6.0. The nitrite-scavenging rate in tea extracts/amine/nitrite systems proved to be faster than that in amine/nitrite systems. To screen the nitrite-scavenging factors, tea extracts were fractionated into water-soluble, methanol-soluble, methanol-precipitate and crude catechin fraction. Among these fractions of tea extracts, the crude catechin fraction possessed greater nitrite-scavenging action than the other fractions. The nitrite-scavenging action of tea extracts increased with the contents of total phenols and an absorbance at 280nm, nitrite-scavenging factors were supposed to be and catechins in tea polyphenol compounds.

• 동아시아식생활학회지
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• 제21권2호
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• pp.243-249
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• 2011

This study investigated the physiological and antioxidant activities of green, oolong, and black tea extracts. The crude catechin extract yields of green, oolong, and black tea were 4.9%, 3.4%, and 2.5%, respectively. Total phenol contents of green, oolong, and black tea were 40.9%, 43.0%, and 38.5%, respectively. The order of the electron donating abilities of green, oolong and black tea were green tea>oolong tea>black tea extracts. The SOD-like activities of green, oolong and black tea extracts at 5,000 ppm were 21.2%, 17.5% and 13.9%, respectively. The nitrite-scavenging abilities of green, oolong and black tea extracts were higher than that of ascorbic acid (p<0.05). Antioxidant activities in soybean oil substrates at 500 ppm were in the order of green tea>oolong tea>black tea${\geq}$BHT (200 ppm). Therefore these results showed that the physiological and antioxidant activities of green tea were better than those of oolong and black tea.

• 생명과학회지
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• 제7권4호
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• pp.309-315
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• 1997

The fermented black tea with tea fungus (FBTF) was prepared by culturing tea fungus biomass in black tea with 10% sucrose (BT) at 30$\circ$ for 14 days. The flavor quality of FBTF was investigated by sensory and chemical analysis, and the results were compared with BT. The data of sensory analysis indicated that fruity, wine-like, sharp-pungent, and vinegar-like flavor notes were increase, while earthy note was reduced during fermentation. GC-MS analysis of volatile compounds collected from FBTF and BT by Tenax trap showed that linalool, liinalool oxide other flavor compounds known as black tea flavor compounds were disappeared. Some major flavor compounds produced during fermentation were acetic acid, ethanol, limonene, $\alpha$-terpineol, and these volatiles may be attributed to the flavor of characteristic FBTF. Biosynthetic pathway for the formation of limonene and $\alpha$-terpineol are proposed through mevalonic acid pathway using acetic acid as precusor and/or through transformation of linalool and linalool oxide.

• 한국식품위생안전성학회지
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• 제31권2호
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• pp.132-139
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• 2016

본 연구는 다류의 항산화 활성과 항산화 물질 함량에 대한 조사연구를 목적으로 하였다. 총 99건의 다류에 대하여 DPPH (1,1-diphenyl-2-picrylhydrazyl)의 자유라디칼소거에 대한 능력을 가지고 항산화 활성을 조사하였다. 항산화 활성은 차 시료 100 g당 아스코르빈산 당량의 mg(L-아스코르빈산 동등한 항산화 능력, AEAC)과 1회 제공량 당 mg(자유라디칼 소거활성, $FSC_{50}$)으로 나타냈고 시료추출액에서의 폴리페놀 함량은 Folin-Ciocalteu법으로, 플라보노이드의 함량은 Davis변법으로 측정하였고 Vitamin C는 HPLC법으로 분석하였다. AEAC 값은 마테차, 녹차, 홍차, 헛개차, 국화차, 우엉차에서 상대적으로 높은 항산화 활성을 보였다. 폴리페놀 물질은 차에서 자연스럽게 발생하는 중요한 항산화 물질로 홍차, 녹차 그리고 마테차에서 높은 함량을 나타냈다. 플라보노이드는 마테차, 홍차 그리고 마차에서, Vitamin C는 유자차와 녹차에서 높은 함량을 나타냈다. 유형별로는 침출차가 고형차나 액상차보다 높은 항산화 활성을 나타냈다. 연구결과, 다류에는 폴리페놀 함량과 항산화 활성사이에는 높은 상관관계가 있었고 플라보노이드와 항산화 활성사이에는 통계적으로 유의한 상관 관계가 있었다. 즉, 다류의 항산화 활성은 폴리페놀에 의한 영향으로 확인되었다.

• 대한소아치과학회지
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• 제44권4호
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• pp.437-445
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• 2017

이 연구의 목적은 한국인들이 일상적으로 마시는 서로 다른 네 종류의 차 티백을 이용하여 차가운 생수나 뜨거운 생수로 5분 또는 10분 동안 우려내는 일상적인 방법으로 차를 추출하였을 때 각각의 추출물이 Streptococcus mutans 세균막 성장에 미치는 효과를 알아보고자 하였다. 균주는 S. mutans UA 159를 이용하였고 1%의 sucrose와 각각의 차 추출물을 웰 플레이트에 넣고 배양하였다. 추출 온도에 따른 세균막 형성을 비교 했을 때 녹차와 홍차에서 추출 온도가 높을 때 세균막 형성이 적었고 통계적으로 유의하였다(p < 0.05). 추출 시간을 달리 하고 $72^{\circ}C$ 온수로 많은 양을 추출 했을 경우 세균막 형성을 비교 했을 때는 네 종류 차 모두 추출 시간에 대해서 통계적으로 유의하지 않았다. 한편 추출량에 따른 비교에서는 녹차와 홍차의 경우 같은 시간, 같은 온도로 추출하였을 때 추출량이 적다면 오히려 세균막 성장이 증가하였다.

• 한국식품과학회지
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• 제33권1호
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• pp.12-18
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• 2001

본 연구는 다류원료 식물류의 물 추출물에 대해 항산화성을 검토하고 그 항산화 물질(페놀성 화합물, 비타민 C, 셀레늄)을 분석하였다. 대두유에 식물류의 물 추출물을 0.02%(추출고형분 함량, w/w) 첨가하여 $55^{\circ}C$ 공기순환식 인큐베이터에서 36일 저장기간 동안 과산화물가 측정과 $110^{\circ}C$에서 Rancimat 방법에 의해 항산화성을 검토하였으며 첨가제가 들어있지 않은 대두유를 대조구에 사용했고 0.02% BHT 첨가한 대두유는 비교구로 사용하였다. 대조구와 BHT 첨가구에 비해 산화 유도기간이 $55^{\circ}C$에서는 구기자, 우롱차, 귤껍질(진피), 유자, 매실 물 추출물 등이 길었으며 $110^{\circ}C$에서는 우롱차, 인스탄트커피, 유자, 구기자, 오미자, 매실 물 추출물 등이 길었다. 추출고형분 g당 총페놀성 물질 함량은 우롱차, 녹차, 홍차, 커피, 계피, 결명자 물 추출물 등에서 높았고 비타민 C 함량은 커피, 두충, 홍차, 영지, 계피, 감잎, 치커리, 녹차, 우롱차 물 추출물 등에서 높았으며 셀레늄은 모든 물 추출물에서 검출되지 않았다. 이들의 항산화성은 단일 항산화성 물질의 효과에 기인하기 보다는 페놀성 화합물, 비타민 C 등 복합적 효과에 의한 것으로 사료된다.

• 한국식품영양과학회지
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• 제34권6호
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• pp.869-874
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• 2005

녹차 및 발효정도에 따른 약발효차, 중발효차, 홍차 가루를 첨가하여 제조한 식빵의 일반성분, 수분결합력, 무게, 부피, 색도, texture 및 관능검사 측정한 결과는 다음과 같다. 차가루 첨가식빵의 수분함량은 $36.02\~36.44\%$로 대조구 $36.98\%$와 거의 차이가 없었다. 조단백질과 회분 함량은 대조구보다 차첨가구가 높게 나타났다 수분결합력은 녹차 첨가구가 가장 높았고, 발효차 첨가구, 대조구 순으로 높게 나타났다 식빵의 부피와 비용적은 대조구가 가장 높게 나타났고, 발효 차 첨가구, 녹차첨가구 순으로 높게 나타났다. 색도는 대조구에 비하여 발효가 많이 진행된 차가루를 첨가한 식빵일수록 L값은 낮고, a값과 b값은 높게 나타났다. 식빵의 견고성은 발효가 많이 진행된 차가루 첨가구일수록 높게 나타난 반면, 응집성은 발효가 많이 진행된 차가루를 첨가할수록 낮게 나타났다 접착성과 씹힘성은 홍차가루 첨가식빵이 가장 높았다. 관능검사 결과, 색깔, 외관, 질감은 대조구가 가장 높은 기호도를 보였고, 향미와 맛은 녹차 및 약발효차 가루 첨가구의 기호도가 높았으며, 전체적인 기호도는 약발효차 가루 첨가구의 선호도가 가장 높게 나타났다.

• 동아시아식생활학회지
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• 제23권1호
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• pp.44-52
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• 2013

This study investigated hepatic functional improvement and anti-fibrotic effects of water extracts of black tea. Male Sprague-Dawley rats were divided into four groups (normal, control, and two experimental subgroups: Ba, Bb) and observed for 3 weeks. Liver fibrosis in rats developed from carbon tetrachloride ($CCl_4$) administration, except for the normal group. Except for the normal and control group, the two experimental subgroups were fed water extracts of black tea. The food efficiency ratio significantly increased in the experimental group compared to the control group. The experimental group had a significantly lower liver weight compared to the control group. The ratio of liver weight to body weight was significantly lower in the experimental group than the control group. The levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, blood urea nitrogen, and low-density lipoprotein-cholesterol in serum significantly decreased in the experimental group compared to the control group. The values of hydroxyproline and malondialdehyde in liver were even lower in the experimental group than the control group. In observations on liver histology, weaker inflammation and fibrosis were observed in the experimental group compared to the control group. In conclusion, water extracts of black tea help hepatic cells keep their functions, restraining and protecting the liver from impairments caused by $CCl_4$ administration, and can be effective as anti-fibrotic agents.

• 동아시아식생활학회지
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• 제11권4호
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• pp.305-314
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• 2001

The study was conducted to investigate the effect of added green tea and black tea powder on the quality of bread during storage. Tea bread was prepared with 0.1% and 2% concentration of green tea (GT) and black tea(BT) powder. The crude fat contents of GT 2% group and BT 2% group were significantly higher than those of control group. GT l% group and BT l% group. The loaf weight of the control group was the lowest and its loaf volume was the highest. Especially, GT 2% group had the lowest loaf volume. The internal lightness value of control group was the highest. the redness value of BT 2% group and the yellowness value of GT 2% group were the highest. GT 2% group was significantly higher in hardness and gumminess and BT l% group was higher in cohesiveness and springiness. After 5 day storage, the retrogradation of GT 2% group was the highest and that of BT 2% group was the lowest among groups. After 5 day storage. pH. titratable acidity and total colony count of GT 2% group was the lowest and those of control group was the highest. The sensory score of control, GT l% and GT 2% group were evaluated higher than others. The shelf-life of tea breads were prolonged to 1~3 days by adding green tea powder and black tea powder as compared with the control group. but It must be considered the way to increase the quality of bread in loaf volume and retrogradation.

• Journal of Nutrition and Health
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• 제27권10호
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• pp.1007-1017
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• 1994

In order to investigate the effect of Korean green tea, oolong tea and black tea beverage on the antioxidative detoxification in cadmium(Cd) poisoned rat liver, male Sprague-Dawley rat weighing 143$\pm$3.2g were divided into control and experimental groups. The experimental groups were fed standard diet containing 40ppm Cd and were given distilled water(CD), 5% black tea(BT), oolong tea(OT) and green tea(GT), respectively. Tea beverages were extracted from 5G dry leaves of teas in 100ml hot distilled water by the treatment at 85$^{\circ}C$ for 3 min. Liver xanthine oxidase(XOD) activity was increased by the administration of Cd except GT group. Liver superoxide dismutase(SOD), glutathione peroxidase(GSH-px), glutathione S-transferase(GST) activities were decreased by te administration of Cd but did not decreased by the administration of green tea(in GT group). Vitamin E and reduced glutathione contents were significantly decreased in Cd administered groups. Liver lipid peroxide value in Cd administered groups were increased compared to control group, but was not increased in GT group. Serum glutamic oxaloacetic transaminase(GOT) activities in CD, OT, BT groups were higher than control, but that in GT group was similar to control group. Serum glutamic pyruvic transaminase(GPT) activity was not significantly different among various groups. It was concluded that green tea might alleviate peroxidative damage in Cd-administered rat liver by reinforcing antioxidative detoxification system.