INHIBISI INSEKTISIDA KARBAMAT DAN ORGANOFOSFAT PADA ASETILKHOLINESTERASE LEBAH MADU

Abstract

It is generally already accepted that organophosphate and carbamate insecticides function due to their ability to disrupt the transmission of impulses at certain synaptic junctions in the nervous system by inhibition of acetylcholinesterase. Type of inhibition reaction of carbamate (Baycarb and MIPC) and organophosphate (Dichlorvos and Monochrotophos) insecticides on honey-bee acetylcholinesterase (AChE) is shown in this investigation. For this study, the enzyme was produced by extraction of honey-bee heads using 0.01 M and pH 7.0 aqueous phosphate buffer solution, while N-methylindoxyl acetate (MIA) in absolute methanol at concentration of 0.005 g/mL was used as a substrate stock solution. Enzyme activity was detected using HPLC spectrofluorometer at 450 nm and 495 nm for excitation and emission wavelength, respectively. Based on detection of initial reaction rate between the enzyme with carbamate or organophosphate, it could be concluded that the reactions were competitive inhibition.

Keywords: inhibition, acetylcholinesterase, carbamate, organophosphate.