苦参碱的水解动态及其在自然水体中的降解特性

农药的降解特性是评价其环境安全性的重要指标。为评价植物源农药苦参碱对水环境的安全性，依据“化学农药环境安全性评价试验准则”，采用室内模拟试验探讨了苦参碱的水解动态及其在自然水体中的降解特性和影响因素。结果表明:苦参碱在不同pH值缓冲液中水解均较缓慢，120 d后水解率仍低于25%，属于难降解型；其在6种自然水体中降解均较快，半衰期在6.3~12.8 d之间，降解速率排序依次为池塘水河水雨水湖水海水自来水；在6种自然水体中（25℃±1℃），苦参碱降解速率随其初始浓度的升高而减慢，半衰期与初始浓度呈正相关，但均小于30 d，属于易降解型。比对试验表明:微生物是影响苦参碱降解速率的主要因素，水体中微生物的量与其降解半衰期呈显著负相关关系（P=0.006）。可见，苦参碱在自然水体中易降解，该特性对于指导苦参碱的实际应用具有重要意义。

Hydrolysis dynamic of matrine and its degradation properties in natural waters

The degradation property of pesticide is an important index for environmental safety assessment. In order to assess the water environmental safety of the botanical pesticide matrine, both the hydrolysis dynamics in sterilized buffer water and degradation properties in natural water were studied according to China national stands Chemical Pesticide Environmental Safety Evaluation Test Guidelines. The results showed that hydrate rate of matrine in buffered water was less than 25% after 120 d. However, it was very faster in natural water system with the half-life ranged from 6.26 d to 2.87 d, and the sequence of hydrolytic speed in different systems was: pool water river water rain lake sea tap-water. The degradation speed displayed a negative correlation with the initial concentration of matrine in 6 kinds of natural water systems (25 ℃±1 ℃), while the half-life would be prolonged as the initial concentration increased. Given that the half-life was less than 1 month, the degradation is relatively easy. The comparative studies indicated that the hydrolytic speed of matrine was mainly influenced by microorganisms in the water, and the half-life was significantly and negatively correlated with the quality of microorganisms (P = 0.006). Above all, matrine would be easily degraded in natural water systems and was safe to water environment.