Fenvalerate induced toxicity in Zebra fish, Danio rerio and analysis of biochemical changes and insights of digestive enzymes as important markers in risk assessment

Fenvalerate is widely used insecticide that severely causes toxicological effects in various aquatic organisms especially in fish. Physiochemical factors of water influenced fenvalerate toxicity. This study investigated physiochemical content of water, the effects of fenvalerate on mortality, changes in protein profile in the gut of Zebra fish and digestive enzymatic changes after 28 days of exposure. Zebra fish was exposed to ranges of fenvalerate and LC50 value was determined. Alkaline pH of the water and high temperature critically influenced mortality. The sub lethal concentration of fenvalerate decreased total protein content in various organs and induced elevated level of free aminoacids. Fenvalerate affected major digestive enzymes activity in the gut of Zebra fish. Protease and amylase assay revealed 39 ± 2.4% protease activity loss and 24.5 ± 5.5% amylase activity loss due to fenvalerate toxicity. Fenvalerate induced disintegration of enzymes from the gut at sub lethal concentration. Fenvalerate reduce the enzyme activity of proteases and amylases significantly. The present finding suggests that accumulation of fenvalerate critically alter not only the biochemical changes in the intestine, but also the specificity of protease and amylase towards various substrates. Keywords: Freshwater, Danio rerio, Fenvalerate, Sub lethal, Mortality, Protease, Amylase