水杨酸对乌龙茶咖啡碱代谢生理特性的影响

Effects of Salicylic Acid on the Physiological Characteristics of Caffeine Metabolism in Oolong Tea

[目的]研究外源水杨酸对乌龙茶咖啡碱合成代谢的影响。[方法]以乌龙茶品种"铁观音"幼苗为试验材料,分析外源水杨酸对乌龙茶叶片咖啡碱含量、咖啡碱合成酶基因表达及其合成途径中间代谢产物含量的影响。[结果]外源水杨酸提高乌龙茶叶片咖啡碱含量、激活乌龙茶咖啡碱合成酶的基因表达,增加咖啡碱可可碱、1,7-二甲基黄嘌呤和茶碱等合成途径中间产物的含量,有利于咖啡碱的累积。[结论]水杨酸对咖啡碱生物合成具有浓度效应,2.0 mmol/L水杨酸最有利于铁观音咖啡碱的生物合成。

[Objective]To study the effects of exogenous salicylic acid on the synthesis and metabolism of caffeine in Oolong tea.[Method]The seedlings of Tieguanyin,a oolong tea variety,were used to study the effects of different concentrations of salicylic acid on the gene expression of caffeine,caffeine synthetase and the content of intermediate products of caffeine synthesis pathway.[Result]Exogenous salicylic acid increased the content of caffeine in Oolong tea,activated the gene expression of caffeine synthetase,and increased the content of theobromine,1,7-dimethylxanthine and theophylline,the intermediate products of caffeine synthesis pathway,so as to promote the biosynthesis of caffeine.[Conclusion]Salicylic acid has a concentration effect on caffeine metabolism,2.0 mmol/L salicylic acid is the most favorable for caffeine production.