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題 名 | 臺灣主要栽培茶樹品種兒茶素含量與抗氧化活性之比較=Comparison of Catechins Contents and Antioxidant Activity of Green Teas from Taiwan Major Tea Cultural Cultivars |
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作 者 | 蔡永生; 劉士綸; 王雪芳; 區少梅; | 書刊名 | 臺灣茶業研究彙報 |
卷 期 | 23 民93.11 |
頁 次 | 頁115-131 |
分類號 | 434.81 |
關鍵詞 | 綠茶; 栽培品種; 兒茶素; 抗氧化能力; Green tea; Tea cultural cultivars; Catechins; Antioxidant activity; |
語 文 | 中文(Chinese) |
中文摘要 | 本研究利用臺灣主要栽培之9個茶樹品種(青心大冇、臺茶12號、臺茶13號、四季春、青心烏龍、青心柑仔、臺茶7號、臺茶8號和臺茶18號),分春、夏、秋3個產季,以炒菁製備的綠茶為茶樣,分析及比較其兒茶素含量與其抗氧化活性,以了解臺灣這些主要茶樹品種及不同產季間在兒茶素及其抗氧化活性方面的差異。結果顯示,臺灣主要栽培之9個茶樹品種,總兒茶素含量介於6.62%~21.79%之間,平均含量為12.72±3.32%。在分析的6個個別兒茶素中,以EGCG和EGC兩種兒茶素含量最多,平均約佔70%以上。不同品種之兒茶素含量比較,大葉種(臺茶7號、臺茶8號和臺茶18號)明顯高於其它6個小葉種品種甚多;3個大葉種總兒茶素含量平均為16.1%,6個小葉種總兒茶素含量平均為10.45%,高出至少50%以上;而夏茶亦高於春茶和秋茶。不同品種間兒茶素含量之差異,除了大葉種與小葉種有顯著差異外,其它各品種間之差異並不顯著。但臺茶7號兩個游離型兒茶素EC和C含量相對特別高,與其它品種個別兒茶素含量之大小趨勢(Profile)顯得特別不同。以4種抗氧化力評估方法分析不同品種茶葉之抗氧化力,整體而言,除總抗氧化力(TEAC法)大葉種顯著優於小葉種外,其它三種測定方法並無明顯之差異。本研究採用的茶湯濃度僅1%(1gm in 100 mL 100℃水),不論在清除DPPH能力或清除超氧陰離子能力及螯合亞鐵離子能力平均至少皆達40%以上之清除力,可知平時喝茶的濃度更高(如3gm加150 mL 100℃水),當有更高的抗氧化能力。兒茶素與不同抗氧化力之相關分析顯示,除了EC和ECG、TCG(總酯型兒茶素)和TC(總兒茶素)與總抗氧化力達顯著正相關外,其餘3種抗氧化力皆與兒茶素無顯著關係,推測可能原因為影響茶葉抗氧化力之成份,除了兒茶素外,還有其它多酚類。 |
英文摘要 | Using pan-fried green teas made from nine major tea cultural cultivars (Chin-Shin Da Pan, TTES No. 12, TTES No.13, Si-Ji-Chun, Chin-Shin Oolong, chin-Shin Gan Zai, TTES No. 7, TTES No. 8 and TTES No. 18)in spring, summer and fall seasons in Taiwan as experimental materials, their contents of catechins and antioxidant activities were examined. The purpose of this study was to compare the differences in catechin contents and antioxidant activity among these tea samples as well as the correlation between the catechin contents and antioxidant activities. The results show that the total catechin contents of green tea samples from these nine tea cultural cultivars ranged from 6.62% to 21.79% and the average amount was 12.72±3.32%. Among six individual catechins, the contents of EGCG and EGC were the highest with average above 70% of total catechins. The differences in catechin contents among all tea cultivars were not significant except for the difference between large-leaf-type (TTES No.7, TTES No.8 and TTES No. 18) averaged as 16.1% and 6 small-leaf-type ones averaged only 10.45% (p<0.05). They differed by more than 50%. The catechin contents of summer green tea samples were significantly higher than those of spring and fall ones. The contents of two free types of catechins (EC and C) in TTES No. 7 were found to be very high. It made the catechin profile of TTES No. 7 differ from those of other tea cultivars. Using four different methods to evaluate the antioxidant activities of green tea samples from these nine tea cultural cultivars, it was found that only the TEAC methods could detect the antioxidant activity of large-leaf-type ones better than that of small-leaf-type ones. The concentration of tea samples used in this study was very low at only 1% (1gm tea in 100 gm 100°C water), but they all showed considerably high antioxidant activity (>40%). This indicates that the antioxidant activity should be even higher when we are drinking tea because the concentration of tea is usually at least as 2% (3 gm in 150 mL 100°C water). In terms of correlation analysis of catechin contents and antioxidant activity, the results show that only TEAC was positive-related significantly to EC, ECG, TCG (total ester-type catechins) and TC (total catechins). The antioxidant activity evaluated by the other three methods showed to significant relationship with the catechins (p>0.05). It should probably be pointed out that the components other than ctechins (like polyphenols) also affect the antioxidant activity. |
本系統中英文摘要資訊取自各篇刊載內容。