Analysis for Effect of Dimehypo on Proteolytic Enzyme Activity in the Midgut of the Spider Pardosa pseudoannulata with a Piezoelectric Quartz Crystal Impedance
A piezoelectric quartz crystal impedance technique has been applied for in situ monitoring of the whole process of the proteolytic enzyme-catalyzed hydrolyzation of casein and the effect of pesticide dimehypo (formula: C5H11NNa2O6S4) on the proteolytic enzyme activity in the midgut of the spider Pardosa pseudoannulata, based on its real-time reponses to the density-viscosity change of the tested solution due to the hydrolyzation occurring on the casein molecules. The results indicated that the hydrolyzation was significantly increased in the presence of low-dose dimehypo, where significantly inhibited in the presence of high-dose dimehypo, and a correlation was found precisely between the enzyme activity reflected by the final frequency shift after the hydrolyzation and the concentration of dimehypo, with a significant frequency response observed even at a 2.88 x 10-4 volume ratio of dimehypo to distilled water. The present work may have presented a novel method feasible for study on the mechanism of excitability of spiders under low-dose dimehypo pesticide and quick detection of proteolytic enzyme activity.
W. H. Fu et al., "Analysis for Effect of Dimehypo on Proteolytic Enzyme Activity in the Midgut of the Spider Pardosa pseudoannulata with a Piezoelectric Quartz Crystal Impedance", Advanced Materials Research, Vol. 345, pp. 387-392, 2012