Selection of Phytoesterases Used in Detecting the Residue of Pesticides

Through employment of the enzyme inhibition mechanism of enzymatic analysis,the general esterase activities and the specific activities in seeds from eight plant species and in two botanic processing materials were studied and compared.The results showed that the general esterase activity and the specific activity in seeds from Vigna sp.are 7.325 U and 0.617 U/mg respectively.The esterase obtained from Vigna sp.was then applied to analyze sensitivity to six pesticides(dichlorvos,phoxim,trichlorfon,metolcarb,carbofuran and methomyl).The results showed that the limits of detection were lower than the maximum of residue limit,which meets the national standard of detection.The results indicated that the esterase obtained from Vigna sp.possesses the best general esterase activity,specific activity and sensitivity,which makes Vigna sp.an optimal enzyme source for detecting agricultural pesticides residue.