金银花花中活性成分含量及其相关酶活性的动态变化规律研究

目的: 研究不同花期金银花中活性成分含量及其相关次生代谢过程中关键酶活性的动态变化规律,为确定金银花最佳采收期,调控金银花质量和相关管理规范提供指导. 方法: 测定金银花不同花期苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、过氧化物酶(POD)的活性,以及总酚、总黄酮、绿原酸、花色苷等活性成分的含量. 结果: 从三青期到金花期,金银花中总酚、总黄酮和花色苷的含量呈下降趋势,三青期达到最高值,分别为4.04,6.71,0.26 mg·g^-1,绿原酸在三青期达到最高值,为0.968 mg·g^-1,大白期达到最低值,后又小幅升高.PAL,PPO,POD的活性从三青期逐渐下降,到银花期达到最低值,同三青期相比,三者的下降幅度分别为43%,62%,56%,后到金花期略有上升. 结论: 在金花期之前,金银花中的PPO,POD活性与酚类物质程正相关.在金银花成熟期,由于呼吸作用的加强,诱导POD活性上升,使POD成为金银花成熟阶段催化酚类物质氧化为醌的关键酶,即POD是控制金银花成熟阶段活性成分含量的关键酶.

Dynamic changes of enzyme activities and active component contents in Lonicera japonica during different blossoming stages

Objective: This paper aimed to study the dynamic changes of enzyme activities and active component contents in Lonicera japonica during different blossoming stages. Method: The enzyme activities of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), peroxidase (POD) and the contents of total phenol, total flavonoids, chlorogenic acid, anthocyanins in L. japonica during different blossoming stages were determined. Result: The contents of total phenolics, total flavonoids, anthocyanins decreased from the Sanqing stage to Jinhua stage while the content of chlorogenic acid increased slightly in white period, and then decreased gradually. The activities of three enzymes decreased gradually from Sanqing stage, and got to a minimum value in Yinhua stage, then increased slightly until the Jinhua stage. Conclusion: The enzyme activities of PPO and POD correlated the content of phenolic substances positively before the Jinhua stage in L. japonica. In the period of maturity, the POD activity was strengthened due to the induction of respiration and became the key enzyme to control active component content during the mature stage.