对不同季节茶树新梢不同部位鲜叶中儿茶素组分和非酯型儿茶素合成酶的变化规律进行了研究。结果表明,在茶树新梢上,从芽到第四叶,四种非酯型儿茶素中除了GC外,C、EC和EGC含量均逐步增加;两种非酯型儿茶素合成酶中,DFR/LAR活性呈下降趋势,而ANR在第三叶中达到最高。相关分析进一步表明,不同部位鲜叶中儿茶素的总量变化与DFR/LAR活性变化呈显著正相关,而与ANR变化相关性不大。
The changes of non-galloylated catechins and relative enzymes as well as the composition of catechins in different parts of tea shoots and in different seasons were investigated in this paper. The results showed that the contents of non-galloylated catechins except GC increased gradually from bud to the fourth leaf. Both of two synthetical enzymes related to non-galloylated cahechins, the activity of DFR/LAR declined gradually, but the activity of ANR was the highest in the third leaf. The result of correlation analysis showed that the contents of total catechins in different tea leaves presented a prominent positive correlation with the activity of DFR/LAR,but not with the activity of ANR.
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