The effect of immobilized chitinase enzyme on the biocontrol of Sitophilus zeamais

Microbial enzymes produced using biological processes are of great importance due to their contribution to sustainable solutions for agricultural production. In our previous study, the chitinase enzyme from Lactobacillus coryniformis was purified, immobilized to zinc oxide (ZnO) nanoparticles , its effectiveness as a bioinsecticide against the storage pest Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae) was determined by forming a nanoformulation. In this study, the effectiveness of immobilized chitinase (nanoformulation), free chitinase, malathion, ZnO, , L. coryniformis on intestinal enzymes such as alkaline phosphatase (ALP), adenosine triphosphatase (ATPase), and lactate dehydrogenase (LDH) were tested to elucidate some of the mechanism of insect death. The effects of the applications on the activity of ALP, ATPase, and LDH enzymes were found to be statistically significant (p < 0.01). The lowest activity in the ALP enzyme was measured in Malathion and 8 mg/L applications. While the lowest activity in the ATPase enzyme was measured in the 8 mg/L application, the lowest activity in the LDH enzyme was observed in the malathion and 6 mg/L applications. Applications caused a decrease in enzyme activities (LDH, ALP, and ATPase). This situation affected the intestinal activities negatively, disrupted the feeding physiology of the insect, and caused its death. Obtained results showed that the formulation created may have an important role in the protection of corn from this pest.