Yoshino K, Hara Y, Sano M, Tomita I
Department of Chemistry and Biochemistry, Numazu College of Technology, Shizuoka, Japan.
Biol Pharm Bull. 1994 Jan;17(1):146-9. doi: 10.1248/bpb.17.146.
The antioxidative activity of theaflavins (TFs) and thearubigin (TR) purified from the infusion of black tea leaves was examined using the tert-butyl hydroperoxide-induced lipid peroxidation of rat liver homogenates. The concentrations which produced 50% inhibition of lipid peroxidation (IC50) by theaflavin (TF), theaflavin monogallate-A (TFM-A), and TR were 4.88 x 10(-4), 4.09 x 10(-4), and 4.95 x 10(-4%) (w/v), respectively. The anti-oxidative activity of these compounds was higher than that of glutathione, L(+)-ascorbic acid, dl-alpha-tocopherol, butylated hydroxytoluene, butyl hydroxyanisole, etc., but was lower than the activity of (-)-epicatechin gallate, (-)-epigallocatechin, and (-)-epigallocatechin gallate. As to the IC50 in molarity, the antioxidative activity of TFM-A was the second highest among all the samples used in this study. The antioxidative activity of lyophilized tea infusions was compared. The activity of black tea was about as potent as that of green tea. These results suggest that black tea infusion containing TFs and TR could inhibit lipid peroxidation in biological conditions in the same way as green tea infusion containing epicatechins.
利用叔丁基过氧化氢诱导大鼠肝脏匀浆脂质过氧化反应，对从红茶茶叶浸出液中纯化得到的茶黄素（TFs）和茶红素（TR）的抗氧化活性进行了检测。茶黄素（TF）、单没食子酸茶黄素 -A（TFM-A）和TR产生50%脂质过氧化抑制率（IC50）的浓度分别为4.88×10⁻⁴、4.09×10⁻⁴和4.95×10⁻⁴%（w/v）。这些化合物的抗氧化活性高于谷胱甘肽、L（+）-抗坏血酸、dl-α-生育酚、丁基羟基甲苯、丁基羟基茴香醚等，但低于（-）-表儿茶素没食子酸酯、（-）-表没食子儿茶素和（-）-表没食子儿茶素没食子酸酯。就摩尔浓度的IC50而言，TFM-A的抗氧化活性在本研究使用的所有样品中排名第二。对冻干茶浸出液的抗氧化活性进行了比较。红茶的活性与绿茶相当。这些结果表明，含有TFs和TR的红茶浸出液与含有表儿茶素的绿茶浸出液一样，能够在生物条件下抑制脂质过氧化。
