Enzyme inhibitory potency of nano formulation of some plant oils on the red palm weevil Rhynchophorus ferrugineus olivier

Abstract

Inhibitory effect of the tested plant oils and their nanoformulation against trypsin and chymotrypsin enzyme extracted from Rhynchophorus ferrugineus, was studies in in vivo and in vitro. In vivo inhibition, the reduction in the trypsin specific activity caused by the bulk oils was greater than that of chymotrypsin enzyme. Compared to control nanoformulation caused significant reduction in the specific activity of trypsin enzyme; however, there were no inhibition effect observed on chymotrypsin enzyme. In vitro bulk oils showed very low inhibitory effect against trypsin enzyme, while they showed strong inhibition activity against chymotrypsin with recording for ginger nanoformulation (half-maximal inhibitory concentration (IC50) =6.83 μg/ml), purple nutsedge (7.632 μg/ml), garden cress (11.52 μg/ml) and castor (16.82 μg/ml), nanoformulation of these oils showed uncompetitive type of inhibition as the Vmax and Km values changed compared to control. In conclusion, nanoformulation of the tested plant oils could be used in the integrated pest management (IPM) programs of the red palm weevil (RPW).