Detection the organophosphorous pesticide residues in vegetables using the esterase of Araneus ventricosus (Araneae)

A technique for detection of organophosphorous(Ops) pesticide residues was explored by measuring the activities of esterase from Araneus ventricosus.The results were showed that the esterase activities in abdomen from the adult female spider were higher than that in cephalothorax.The esterase activity was the highest under 37℃ and with pH 7.0 of phosphate buffer solution.There was a significant liner regression between the concentration logarithm of dimethoate and the inhibitory rate of esterase.The Ops pesticide residues can be detected by measuring the inhibitory rate of vegetables washing liquid to the esterase from the spider.The detection limit of dimethoate was 0.509 4 mg/L by this method.The Ops pesticide residues in three species of vegetables were lower than the standard values given by Chinese government and FAO/WHO.