Characterization of a novel alkaline lipase from Pseudomonas sp. HCU2-9 for detergent formulation

Abstract

A novel alkaline lipase was purified and characterized from Pseudomonas sp. HCU2-9. The lipase was purified to homogeneity using ammonium sulphate precipitation and gel filtration chromatography. The molecular weight of lipase was approximately 45 kDa by SDS-PAGE. The lipase showed maximal activity at pH 9 and 60C, respectively. The enzyme was stable in the pH range 5-9 for 30 min and at 45-55°C for 60 min. Higher activity was observed in the presence of Ca2+, Mg2+, Mn2+ ions, Tween 80 and Triton X-100 while Co2+, Cu2+, Zn2+ ions, DTT and PMSF showed inhibitory effect. The enzyme hydrolyzed both synthetic and natural triglycerides with maximum activity for tripalmitin and palm oil, respectively. It also hydrolyzed esters of p-nitrophenol with highest activity for p-nitrophenyl palmitate. Organic solvents were found to have little effect on the activity of the lipase. The enzyme showed stability towards selected commercial detergents, oxidizing agents and protease. The remarkable resistance capability of the lipase makes it a potential additive for better detergent formulation