Production of lipase and protease from an indigenous Pseudomonas aeruginosa strain and their evaluation as detergent additives: compatibility study with detergent ingredients and washing performance

An indigenous Pseudomonas aeruginosa strain has been studied for lipase and protease activities for their potential application in detergents. Produced enzymes were investigated in order to assess their compatibility with several surfactants, oxidizing agents and commercial detergents. The crude lipase appeared to retain high activity and stability in the presence of several surfactants and oxidizing agents and it was insusceptible to proteolysis. Lutensol? XP80 and Triton? X-100 strongly activated the lipase for a long period (up to 40 and 30% against the control after 1h) while the protease activity was enhanced by the addition of Triton? WR1339 and Tween? 80. The washing performance of the investigated surfactants was significantly improved with the addition of the crude enzyme preparation. Studies were further undertaken to improve enzymes production. The optimization of fermentation conditions led to an 8-fold increase of lipase production, while the production of protease was enhanced by 60%.