• Food Science and Biotechnology
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• 제18권5호
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• pp.1212-1217
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• 2009

This study examined the influence of manufacturing processes and extraction conditions on the chemical compositions of green tea. Green tea samples grown in various areas (Korea, China, and Japan) and processed by 4 different methods (steaming, pan-firing, steaming and pan-firing, and heavy roasting after steaming and pan-firing) were collected for study. The chemical compositions of the green tea extracts and infusions were different according to their processing methods and extraction conditions, including catechins, caffeine, and free amino acids contents. In all samples analyzed, (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC), and theanine were determined as the major catechins and free amino acid, respectively. Studies of samples grown in the same area (Jeju; Korea) showed that there were significant differences in the concentrations of catechins and caffeine in extract and infusion according to the processing methods. These results indicate that processing methods influenced the chemical compositions of the green tea extracts and infusions.

• 한국약용작물학회지
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• 제19권4호
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• pp.276-286
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• 2011

Morus alba (Mulberry) leaves were exposed to fermentation for varying amounts of time: no fermentation (0 min, MANF), medial fermentation (10 h, MAMF), and full fermentation (24 h, MAFF). The chemical compositions of the teas were determined and compared with those of commercial Camellia sinensis teas. The results showed that mulberry leaf teas contained significantly higher amounts of ash and fat than Camellia sinensis tea. Compared with Camellia sinensis teas, all mulberry leaf teas contained significantly more total free amino acids (24.26~54.25mg L-glutamic acid equivalent $g^{-1}$), but the concentration of caffeine was relatively low for mulberry leaf teas. High thiamine, riboflavin, and niacin contents were found in all mulberry leaf teas, but ascorbic acid and pyridoxine were found at higher levels in Camellia sinensis teas than in mulberry leaf teas. Color measurements demonstrated that mulberry leaf tea infusions generally had lower $a^*$ (greenness) and $b^*$ (yellowness) values than Camellia sinensis tea infusions. All infusions exhibited low turbidity levels (less than 10%). The contents of total phenols were measured as 71.8 and 74.9mg 100 $ml^{-1}$ infusion in MANF and MAFF, respectively, but the MAMF tea infusion showed significantly lower total phenols (64.6mg 100$ml^{-1}$ infusion). The total flavonoid contents of mulberry leaf tea infusions were lower (8.9~20.6mg 100 $ml^{-1}$ infusion) than those of Camellia sinensis teas and thus had lower antioxidant capacities (DPPH: 326.8~526.9 ${\mu}M$ trolox equivalent $g^{-1}$ and FRAP: 364.6~387.6 ${\mu}M$ trolox equivalent $g^{-1}$) than Camellia sinensis teas. The amounts of ${\gamma}$-aminobutyric acid (GABA) and rutin were higher in fermented mulberry leaf teas; the level of GABA increased with increasing fermentation time and the content was highest in MAFF, but rutin content was highest in MAMF.

• Bulletin of the Korean Chemical Society
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• 제26권5호
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• pp.747-754
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• 2005

Liquid chromatographic methods with UV and fluorescence detection have been used to determine the levels of (+)-catechin, (-)-epicatechin, (-)-epicatechin gallate, and (-)-epigallocatechin gallate in Korean green tea infusions. The extracts of Korean green tea leaves or powders in water at various temperatures (100 ${^{\circ}C}$, 80 ${^{\circ}C}$, 60 ${^{\circ}C}$) and time, were washed with chloroform and re-extracted to ethyl acetate. The ethyl acetate phase was dried and re-dissolved in methanol and analyzed. Five catechin compounds were separated by gradient elution. The flavonoids were found decomposed on prolonged extraction, thus exhaustive extraction by a Soxhlet apparatus was found useless for green tea. Some unknown components were found in the extracts at 100 ${^{\circ}C}$. When the green tea was filtered and re-extracted with new fresh water, still some flavonoids were extracted. However, the contents of flavonoids in the third extract were found negligible. The flavonoid extraction rate of green tea powders was higher than that of green tea leaves, but flavonoid decomposition of green tea powders was also faster than that of green tea leaves. The traditional way of drinking green tea was found appropriate in view of flavonoids intake.

• 한국식품위생안전성학회지
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• 제32권5호
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• pp.389-395
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• 2017

루이보스티에서 5종의 phenolic acid (gallic acid, chlorogenic acid, caffeic acid, p-coumaric acid, trans-ferulic acid)와 9종의 flavonoid (procyanidin b1, aspalathin, rutin, vitexin, hyperoside, isoquercitrin, luteolin, quercetin, chrysoeriol)를 UPLC-MSMS를 이용하여 동시 분석하였다. 14종 페놀릭류를 동시 분석하기 위하여 기기조건과 유효성을 검증하였고 확립된 분석방법을 이용하여 시중에 유통중인 루이보스티 30건을 채취하여 페놀릭류를 분석하였다. 루이보스티 1 g 혹은 1티백에 뜨거운 물 100 mL을 가하여 3분, 6분, 30분이 경과 후 그리고 차가운 물 ($25-30^{\circ}C$)에 30분 우려낸 루이보스티의 페놀릭류 함량을 구하였다. 루이보스티에서 전체 실험대상 페놀릭류 중 rutin과 aspalathin이 가장 많이 추출되어 나왔으며 각각 물질의 함량은 제품별로 달랐다. 페놀릭류 성분의 추출효율은 14종 페놀릭류의 총합 기준으로 뜨거운 물 30분 > 6분 > 3분 > 차가운 물 30분 순으로 높았다.

• 한국식품과학회지
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• 제31권4호
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• pp.1024-1028
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• 1999

침출수의 pH가 녹차 침출액 성분에 미치는 영향에 대하여 조사하였다. 녹차의 색은 pH의 증가에 따라 Hunter b값, chroma값 및 TCD값이 증가하였으며 총 아미노산 함량은 침출수의 pH에 크게 영향을 받지 않음을 알 수 있었다. 총 카테킨 함량은 pH 4.0, 5.0, 6.0 및 7.0으로 추출하였을 경우 각각 32.28, 31.84, 31.14 및 14.70 mg/g으로 pH 7.0 침출수에서 급격하게 감소하였고, 4종류 카테킨 중 EGCg와 EGC가 pH의 영향을 가장 많이 받음을 알 수 있었다. 카페인 함량은 pH 4.0, 5.0, 6.0 및 7.0으로 추출하였을 경우 각각 15.7, 16.9, 18.0 및 19.2mg/g으로 pH가 증가함에 따라 더 많이 추출됨을 알 수 있었다. 결론적으로 녹차 고유의 색을 유지하고 녹차에 함유 되어 있는 기능성 성분을 효율적으로 침출하기 위해서는 침출수의 pH를 낮게 유지하는 것이 바람직하다고 판단되었다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권6호
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• pp.2923-2933
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• 2016

Recently, we reported an inverse association between high 'mate' intake (infusion of Ilex paraguariensis herb, a staple beverage in temperate South America) and breast cancer (BC) risk. Stronger inverse associations were found in high strata of tea, vegetable, fruit and energy intakes, and in overweight/obese women, suggesting possible roles for 'mate' mainly from its antioxidant contribution. The present study attempted to thoroughly explore possible associations among 'mate' and tea intake, dietary antioxidants and BC risk. Combining two databases of previous studies, 572 BC incident cases and 889 controls were interviewed with a specific questionnaire featuring socio-demographic, reproductive and lifestyle variables, and a food frequency questionnaire (64 items), focusing on 'mate' intake (consumer status, daily intake, age at start, age at quit, duration of habit). Food-derived nutrients were calculated from available databases. Odds ratios (OR) and their 95% confidence intervals were calculated through unconditional logistic regression, adjusting for relevant potential confounders. The highest 'mate' intake was significantly inversely associated with BC risk for both low and high carotenoids (OR=0.40 vs. 0.41), vitamin C (OR=0.33 vs. 0.50), vitamin E (OR=0.37 vs. 0.45), flavonols (OR=0.38 vs. 0.48) and reduced glutathione (OR=0.48 vs. 0.46) strata. High tea intake showed significant inverse risk associations only with high carotenoids (OR=0.41), vitamin E (OR=0.48) and reduced glutathione (OR=0.43) strata. In conclusion, a strong and inverse association for 'mate' intake and BC was found, independent of dietary antioxidant levels. Also strong inverse associations with tea intake were more evident only at high levels of certain dietary antioxidants.

• 생명과학회지
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• 제14권2호
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• pp.291-295
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• 2004

루이보스(Aspalathus linearis; RB)는 콩과식물로서 남아프리카 Cape Province의 북서부 산악지역에 자생한다. 루이보스차 침제는 가는 가지와 잎의 발효산물로서 플리보노이드류와 페놀산이 있어 강한 항산화활성을 갖는 것으로 알려져 있다. 본 연구에서는 저산소증모델에서 루이보스차 침제가 배양한 흰쥐 대뇌세포의 스트레스를 완화하는지에 대한 연구하였다. 배지로 누출된 LDH의 정량실험에 의하면 루이보스는 정상산소환경 및 저산소증에서 함량 의존적으로(10-100 $\mu\textrm{g}$/ml) 각각 6-18% 및 2-24%의 세포생존율을 증가시켰다(16 DIV 세포, 처리 후 3일째). CFP-Hsc70 단백질을 표현시킨 신경세포의 모양을 관찰하였을때 루이보스(50 $\mu\textrm{g}$/ml)는 저산소처리 후 5일에 세포체에 수포가 있는 세포의 수를 대조군(55.4$\pm$4.59%)에 비하여 유의하게 감소시켰다(40.9$\pm$6.3%). 이러한 결과들은 루이보스차가 저산소증에서 신경세포를 보호함을 의미하며, 신경세포 손상을 예방 또는 치료하는데 응용될 수 있을 것으로 보인다.

• 한국식품과학회지
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• 제42권1호
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• pp.21-26
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• 2010

국내산 재래종 및 가공녹차를 이용한 미생물발효차의 개발 가능성 및 발효과정중의 특성 변화를 검토하고자 국내산 재래종 및 가공녹차, 야부키타종, 그리고 대차종을 이용한 미생물발효차를 제조하고 발효과정 중 품질 특성을 조사하였다. 모든 원료에서의 미생물발효차의 발효특성은 발효가 진행될수록 적색도 및 황색도가 증가하였고, 클로로필과 탄닌 함량은 감소하였다. 총 질소 및 카페인의 함량은 발효가 진행됨에 따라 큰 변화를 보이지 않았으나 총 catechin 및 개별 카테킨류 중 catechin, ECG, EGCG의 함량은 꾸준히 감소하였다. 그리고 EC와 EGC의 함량은 25일까지 증가하다가 그 이후 감소하였다. 대차종 및 야부키타종의 경우 발효가 진행됨에 따라 항산화활성이 감소한 반면, 국내산 재래종 및 가공녹차는 그 활성을 그대로 유지하였다. 국내산 재래종 및 가공녹차는 발효가 진행됨에 따라 대차종 및 야부키타종과 유사한 발효 양상을 나타냈으나 수색이나 카테킨 및 카페인 등의 성분 함량은 다소 차이를 보였다. 본 연구로부터 국내산 재래종 품종의 찻잎 및 이를 이용하여 제조된 녹차의 미생물발효차 제조가능성을 확인할 수 있었다.

• 한국산학기술학회논문지
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• 제14권11호
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• pp.5646-5657
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• 2013

본 연구에서는 뽕잎차와 Monascus pilosus로 발효시킨 뽕잎차가 ICR mouse의 체중과 간 조직 항산화계 효소류의 활성에 미치는 영향을 조사하고자 음용수 대신 1% 열수 추출액을 8주간 급여하고 체중, 장기중량, 혈액 및간기능 바이오 마커들의 변화를 관찰하였다. Mice는 뽕잎차(UMI)와 발효뽕잎차의 열수추출액 급여군(FMI) 및 정상대조군(NC) 등 3개군으로 나누었다. 차 추출액을 급여한 군들은 유의한 차이는 보이지 않았으나 NC군에 비하여 체중 증가량이 감소하였고, LDL-콜레스테롤, 동맥경화 지수는 유의한 수준의 감소를 보였으며, 간 조직의 lipid peroxide (LPO) 함량 및 xanthin oxidase (XO) 활성의 감소와 glutathione S-transferase (GST) 활성의 유의적인 증가를 관찰할 수 있었다. 이상의 실험결과, 뽕잎차 및 M. pilosus로 발효시킨 뽕잎차는 체중감소 효과가 있으며 간 조직 손상과 관련된 항산화계 효소의 활성을 높여주는 효과가 있는 것으로 사료된다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1453-1461
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• 2016

Regarding 'mate' intake (infusion of Ilex paraguariensis herb, a staple beverage in temperate South American regions), most epidemiologic studies showed positive associations with risk of some cancers, (e.g. upper aerodigestive tract), but evidence on breast cancer (BC) risk is limited to a previous multi-site study, which reported a non significant odds ratio [OR]=0.85, 95% confidence interval [95% CI] 0.67-1.09, p for trend=0.31) for the highest quartile of intake. The present study was conducted in order to further assess associations of 'mate' intake with BC risk. We combined two databases of women belonging to public and private healthcare hospitals. The sample included 572 BC incident cases and 889 controls interviewed with a specific questionnaire featured by socio-demographic, reproductive and lifestyle variables, and a food frequency questionnaire of 64 items, also analyzing 'mate' intake (consumer status, daily intake, age at start, age at quit, duration of habit, intensity of intake). ORs and their 95%CI were calculated through unconditional logistic regression, adjusting for relevant potential confounders. The highest quartile of 'mate' intake was inversely associated with BC risk (OR=0.40, 95%CI 0.26-0.57, p for trend <0.001). Stratified analyses also displayed strong significant inverse associations for 'mate' in frequent tea drinkers (OR=0.22), high energy intake (OR=0.23), high body mass index (OR=0.29) and in postmenopausal women (OR=0.36), among other results. As conclusions, we found evidence of a significant inverse association for 'mate' intake and BC risk.