Production of thermotolerant, detergent stable alkaline protease using the gut waste of Sardinella longiceps as a substrate: Optimization and characterization

enhanced the protease activity by 40%. The protease retained an activity of 93, 103, 90 and 98% against urea, β-mercaptoethanol, SDS and tween 80 respectively. The alkaline protease was compatible with all the commercial detergents tested with the residual activity above 90%. The alkaline protease exhibited 22% higher activity on the tryptone soya substrate. The gut waste of S. longiceps is a worthy low cost substrate for the production of industrially important alkaline protease.