南鳳山臺灣山茶不同品系主要化學成分及抗氧化活性之分析;Analysis on main chemical component content and antioxidant activity of different Camellia formosensis (Theaceae) from Nan-Fang Mountain

本試驗分別以六龜試驗林生產之臺灣山茶綠茶（扇平地區綠心芽、紅心芽品系）及紅茶（扇平地區、南鳳山地區綠心芽品系）與市售之茗品綠茶、紅茶進行抗氧化活性比較，分析總酚類化合物與總黃酮類化合物含量，並評估其清除DPPH自由基之活性，同時以高效能液相層析儀對各種茶葉之兒茶素成分進行定量分析。試驗結果顯示，六龜試驗林所生產之臺灣山茶綠茶，無論紅心芽（GR）或綠心芽（GG）品系皆具有極佳的抗氧化活性，其清除DPPH自由基能力（IC50＝ 3.29 ± 0.03 μg/mL（GR）；3.43 ± 0.09 μg/mL（GG））與總抗氧化活性（5.34 ± 0.18 mM of Trolox (GR)；5.36 ± 0.06 mM of Trolox (GG)）皆顯著優於市售綠茶。紅心芽與綠心芽綠茶之總酚類含量分別為390.58 ± 1.78 mg/g與390.04 ± 1.53 mg/g，顯著高於其他市售綠茶；至於紅茶則以南鳳山地區生產之紅茶抗氧化活性較佳，但其清除DPPH自由基能力（IC50＝ 7.17 ± 0.08 μg/mL）、總抗氧化活性（1.97 ± 0.05 mM of Trolox）與總酚類含量251.66 ± 1.24 mg/g仍略遜於市售紅茶。此外，根據HPLC成分分析結果顯示，臺灣山茶綠茶之主要化學成分包括EGCG（298.2 ± 1.8 - 306.5 ± 0.6 mg/g of tea）、Caffeine（82.6 ± 2.2 - 93.0 ± 1.8 mg/g of tea）以及ECG（26.4 ± 1.3 - 27.4 ± 0.7 mg/g of tea）三種成分含量最高；而紅茶則以Caffeine（170.8 ± 7.8 - 242.1 ± 2.1mg/g of tea）及EGCG（109.0 ± 0.2 - 110.7 ± 1.0 mg/g of tea）為其主要成分。其中，綠茶之EGCG、GCG以及ECG等三種兒茶素含量皆顯著高於其他市售茶類，顯示六龜地區臺灣山茶優異的抗氧化活性乃來自於其含有豐富的兒茶素成分且極具市場競爭優勢。
The objective of this study is to evaluate the antioxidant activity and total phenolic contents of different provenance of Camellia formosensis from Loukuei Research Center (Shanping and Nan-Fang Mountain), 10 kinds of commercial tea were also compared. The catechin contents of hot water extracts from various tea specimens, including (-)-epigallocatechin gallate (EGCG), epicatechin, gallocatechin gallate (GCG), (-)-epicatechin gallate (ECG), and caffeine were quantified by using high performance liquid chromatography (HPLC). Results revealed that the total phenolic content of hot-water extract from green tea of C. formosensis (390 mg of GAE/g) were higher than those in commercial teas (259.8 – 297.8 mg of GAE/g), while the total phenolic content from black tea of C. formosensis were 200.04 – 251.66 mg of GAE/g. Both the green and red sprout strain of green tea made from C. formosensis which have the greatest effectiveness in scavenging DPPH free radical, and the DPPH free radical scavenging activity of black tea were equivalent to the average of commercial teas. As to the results from HPLC analyses showed that EGCG (298.2 ± 1.8 - 306.5 ± 0.6 mg/g of tea) was the dominant component of hot-water extracts from green teas of C. formosensis, and Caffeine (170.8 ± 7.8 - 242.1 ± 2.1mg/g of tea) and EGCG (109.0 ± 0.2 - 110.7 ± 1.0 mg/g of tea) comprised the major component of hot-water extracts from black teas of C. formosensis. Moreover, in addition to had an excellent antioxidant activity, the total catechin in hot-water extracts of green teas from C. formosensis were found to be significantly higher than commercial teas, and they could be more competitive than commercial products.