Abstract:

In order to screen an esterase source for rapid determination of organophosphorus pesticide residues, the changes in catalytic activity of esterases from wheat, corn, soybean and rice to α-napthyl acetate were investigated during the development period from seed to seedling, and the catalytic activities of esterase from different parts of wheat seeds were compared. The results indicated that for all the four crops, the esterase activity presented general declining trend during the sprouting and seedling periods and the catalytic activities of esterase from seeds decreased in the following order: wheat, corn, rice and soybean. Seeds of wheat Longmai 26, Yumai 39 and Mai 976189 showed higher esterase activity than the others and the highest esterase activity was observed in the brans of wheat Longmai 26. The bran of wheat Longmai 26 is therefore, highly recommended as an esterase source for fast detection of phosphate pesticide residues.

Key words: plant esterase, α-napthyl acetate, catalytic activity, organophosphorus pesticide