Titanium dioxide nanoparticles relieve biochemical dysfunctions of fifth-instar larvae of silkworms following exposure to phoxim insecticide

Phoxim insecticide is widely used in agriculture, which is toxic to insect pests and nontarget organisms. The phoxim poisoning is hard to prevent for silkworms. TiO2 NPs have been widely applied in whitening, brightening foods, toothpaste or sunscreens, and orally-administered drugs. However, whether TiO2 NPs can increase resistance of silkworm to phoxim poisoning has not been reported. The results demonstrated that added TiO2 NPs significantly decreased reduction of protein, glucose and pyruvate contents, lactate dehydrogenase, succinate dehydrogenase and malate dehydrogenase activities, and attenuated increases of free amino acids, urea, uric acid and lactate levels, activities of protease, alanine aminotransferase and aspartate aminotransferase in the hemolymph of silkworms caused by phoxim exposure. From the present study, it is clearly evident that added TiO2 NPs may relieve toxic impacts of phoxim insecticide on silkworm metabolism, which in turn may result in an increase in silk yield. Crown Copyright (C) 2012 Published by Elsevier Ltd. All rights reserved.