肾叶天胡荽精油的超临界CO2萃取、成分分析及杀虫活性初探

采用正交实验设计，对肾叶天胡荽（Hydrocotyle wigordi Maxim．）精油超临界CO2萃取条件进行了优化，并用GC—MS分析技术对精油的化学成分进行了鉴定，初步探讨了肾叶天胡荽精油对小菜蛾2龄幼虫的触杀活性。结果表明，肾叶天胡荽精油超临界CO2萃取的最佳条件为萃取压力35MPa、萃取温度50℃、解析压力5MPa、解析温度40℃、萃取时间75min、CO2流量34—36L·h^-1，精油得率最高可达5．32％。从精油中共鉴定出19种成分，总相对含量达到89．266％，主要成分为邻苯二甲酸二辛酯（64．302％）。用超临界CO2萃取技术提取的肾叶天胡荽精油对小菜蛾2龄幼虫有一定的触杀作用，20g·L^-1精油对小菜蛾2龄幼虫的24h校正死亡率高达90．00％。

Supercritical CO2 extraction and component analysis of essential oil from Hydrocotyle wilfordi and preliminary study of its insecticidal activity

The optimal conditions of supercritical CO： extraction for essential oil from Hydrocotyle wilfordi Maxim. were selected by orthogonal test design, and the chemical components in the essential oil were identified by GC-MS. The contact toxicity of the essential oil against the 2nd instar larvae of Plutella xylostella L. was studied preliminarily. The optimal conditions of supercritical CO2 extraction are as follows： extraction pressure 35 MPa, extraction temperature 50 ℃, separation pressure 5 MPa, separation temperature 40 ℃, extraction time 75 min and CO2 flow 34 - 36 L · h^-1. And the highest extraction rate of the essential oil reaches 5.32%. Nineteen components in the essential oil have been identified, which account for 89. 266% of the total relative content of the essential oil. The major component is bis （2-ethylhexyl）-phthalate （64. 302% ）. The essential oil of H. wilfordi has a certain contact toxicity against the 2nd instar larvae of P. xylostella, and the corrected mortality of the larvae treated with 20 g · L^-1 essential oil for 24 h reaches 90.00%.