苦楝叶杀螺效果及机制初步研究

Molluscicidal effect and mechanism of Melia azedarach L. leaves against Oncomelania hupensis

目的研究苦楝叶石油醚提取物杀螺活性及对湖北钉螺软体组织糖原和蛋白质的生理生化影响,并进行鱼毒的测定。方法采用系统分离法分离苦楝叶不同极性部位,按照WHO"杀螺剂实验室终筛法"中的浸杀法筛选苦楝叶杀螺活性部位;采用蒽酮显色法、考马斯亮蓝法分别测定苦楝叶杀螺活性部位对钉螺软体组织糖原和蛋白质含量的影响;用斑马鱼急性毒性试验考察其对非靶生物的毒性。结果苦楝叶杀螺活性部位集中于石油醚提取物,经72h处理的LC50为101.6mg/L,并能显著降低钉螺软体组织糖原的含量,减少量为75.61%,且对斑马鱼毒性很小,72h的LC50为285.6mg/L。结论苦楝叶中可能含有安全有效的植物杀螺成分。

Objective To identify the molluscicidal effect and mechanism of Melia azedarach L. leaves against Oncomelania hupensis. Methods Different polar parts of M. azedarach L. leaves were isolated to screen for active compounds. The molluscieidal effects of M. azedarach L. leaves at different concentrations were detected using the laboratory screening methods recommended by WHO. The glycogen and protein contents of O. hupensis treated with light petroleum extract of M. azedarach L. leaves were determined by Anthrone and Coomassie reactions, respectively. Acute toxicity on non- target organisms was determined using Zebrafish as a bioindicator. Results The light petroleum extract of M. azedarach L. leaves was the most active component with snail-killing effects. The LC50 values of the light petroleum extract was 101.6 mg/L after 72 h treatment. The snail glycogen content decreased remarkably （by 75.61%） after treatment with the light petroleum extract. The LC50 value of the zebrafish extract was as small as 285.6 mg/L after 72 h treatment. Conclusion M. azedarach L. leaves may contain safe and effective molluseicidal ingredients.