景宁白茶春茶品质和抗氧化酶活性分析

Analysis of chemical compositions and antioxidative enzyme activities of spring white tea in Jingning,Zhejiang

比较白玉仙茶的2个变种白玉仙茶1号、白玉仙茶2号与其母本白玉仙茶以及当地主要茶叶品种鸠坑和安吉白茶（白叶茶1号）的化学成分和抗氧化酶活性[超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）及多酚氧化酶（PP0）]的差异；研究惠明寺和天堂湖2个不同生态环境和春夏2个不同嫁接时间对这2种茶叶品质的影响．结果显示：白玉仙茶1号的蛋白质、水溶性糖、儿茶素等品质成分含量比其他品种高14．9％～32．1％；白玉仙茶2号的氨基酸含量比其他品种高16．1％～21．8％，且酚氨比低16．0％～33．3％，而色差值显示白玉仙荼2号浸提液的DA值（红度）最大，DB值（黄度）最小，即黄绿色最淡；此外，白玉仙茶1号、白玉仙茶2号中的SOD活性比鸠坑和安吉白荼高6．2％～9．4％，表明它们可能具有较强的抗逆性．对不同产地的比较发现，天堂湖茶叶中各种品质成分的含量比惠明寺的高出5．9％～80．2％，但酚氨比也高11．2％～15．8％，天堂湖白玉仙茶2号的汤色DA值比惠明寺的低17．3％，DB值高20．7％，更偏黄绿；但白玉仙茶1号、白玉仙茶2号的抗氧化酶活性在2个不同环境中无显著性差异．对不同嫁接时间的比较发现，春天嫁接比夏天嫁接更有利于茶叶中主要化合物的积累．白玉仙茶1号在春天嫁接，各品质成分含量比在夏天嫁接提高了27．4％～42．2％，汤色的DA值增大了6．0％，绿度较浅，而白玉仙茶2号在春天嫁接，水溶性糖可多出47．4％，汤色DA值减小了12．5％，DB值增大了16．5％，较为黄绿；嫁接时间对这2种茶叶的抗氧化酶活性没有显著影响．

The contents of main chemical compositions and the activities of superoxide dismutase （SOD）, peroxidase （POD）, catalase （CAT） and polyphenol oxidase （PPO） in Baiyuxian white tea 1, Baiyuxian white tea 2, their female parent Baiyuxian white tea, Jiukeng and Anji white tea （White leaf tea 1） in Jingning County were measured and analyzed. The effects of ecological environment and grafting time on tea quality were also investigated. The results show that the contents of protein, soluble sugar and catechins in Baiyuxian white tea 1 were 14.9 %-32.1% higher than those of other varieties. The amino acid content in Baiyuxian white tea 2 was 16.1 %-21.8% higher and the ratio of polyphenol to amino acid was 16.0%-33.3% lower than those of other varieties. The chromatic aberration results of tea infusion showed that Baiyuxian white tea 2 had the highest DA （red degree） and lowest DB （yellow degree）, which indicated that it had the lightest hues of yellow and green. Moreover, the SOD activities of Baiyuxian white tea 1 and Baiyuxian white tea 2 were 6.2%-9.4% higher than that of Jiukeng and Anji white tea, indicating the former had stronger adversity resistance. The effects of ecological environment on tea quality showed that the chemical contents of tea leaves in Tiantang Lake area were 5.9 %-80.2% higher than those in Huiming Temple area, and the ratio of polyphenol to amino acid was 11.2%-- 15.8% higher. The chromatic aberration of Baiyuxian white tea 2 infusion in Tiantang Lake area was yellower （DB was 20.7% higher） and greener （DA was 17.3% lower） than that in Huiming Temple area. However, there were no significant differences on the antioxidative enzyme activities between Baiyuxian white tea 1 and Baiyuxian white tea 2 in the two ecological environments. The effects of different grafting seasons on tea quality showed that it was more beneficial for the accumulation of chemical compounds in tea leaves when tea trees were grafted in spring than in summer. Grafted in spring, Baiyuxian white tea 1 had 27.4%-42.2% more chemical contents and its infusion had a lighter green hue （DA was 6.0% higher）, and Baiyuxian white tea 2 had 47.4% more soluble sugar with deeper yellow and green infusion （DA was 12.5% lower and DB was 16.5% higher）. However, grafting time had no significant influence on the antioxidative enzyme activities of these two varieties.