Study On Isolation，purification And Pesticide Sensitivity Of Butyrylcholinesterases From Chicken Serum

With the development of modern agriculture, pesticides play an increasingly importantrole in the production of grain, fruits, and vegetables, and the irrational use of pesticides hasalso led to excessive pesticide residues in agricultural products, and it affected the food safetyand agricultural trade. Therefore, it′s important to research and apply simple, economical andrapid technology for detection of pesticide residues, to guarantee the safety of China’s food.The butyrylcholinesterase (BChE) activity was specifically inhibited by organophosphate andcarbamate pesticides, BChE activity changes are important indicators of pesticide toxicology,which can be used as biomarkers for the toxicity of pesticides.For the first time，chicken serum BChE was isolated and purified from chicken serum asthe research object in this paper. And its basic enzymology properties were studied.Furthermore, the pesticide sensitivity of BChE from chicken serum and horse serum werestudy with seven organophosphoru pesticides and six carbamate pesticides.The results were as follows:1. The chicken serum BChE was purified by ion-exchange chromatography on DEAESephadex A-50and gel filtration on Sephacryl S-200. Finally the enzyme was purified37.72folds and the enzyme activity recovery ratio was31.69%, and the purified enzyme wasremoved a large amount of miscellaneous protein.2. The Km of chicken serum BChE was60.68μmol/L;the enzyme activity was notinhibited by excess butyrylthiocholine iodide; the optimum reaction pH was8.0and theoptimum reaction temperature was35℃. The sensitivity of chicken serum BChE forphysostigmine was much higher than donepezil hydrochloride.3. Diffent specific activity of chicken serum BChE had no effect on the pesticidesensitivity.4. The sensitivity of chicken serum BChE on the restrain effect of sevenorganophosphoru pesticides from strong to weak was：mevinphos>trichlorfon> dichlorvos> phosphamidon> monocrotophos> phorate andparathion.Chicken serum BChE was insensitive to phorate and parathion.5. The sensitivity of horse serum BChE on the restrain effect of seven organophosphorupesticides from strong to weak was：mevinphos>trichlorfon> phosphamidon>dichlorvos> phorate> monocrotophos>parathion. 6. The sensitivity of chicken serum BChE on the restrain effect of six carbamate fromstrong to weak was：aldicarb> methomyl>metolcarb> carbofuran> isoprocarb>carbosulfan.Chicken serum BChE was insensitive to carbosulfan.7. The sensitivity of horse serum BChE on the restrain effect of six carbamate fromstrong to weak was：carbosulfan> carbofuran> aldicarb> methomyl>metolcarb> isoprocarb.