Optimization and Lipase Production of Lysinibacillus sphaericus in Domestic Oil Rich Waste Water

Abstract

The present study investigated the growth and lipase production by Lysinibacillus sphaericus in a minimal medium. The growth conditions (i.e oil concentration, nitrogen source, carbon source, metals and non metals) were optimized for maximum production of enzyme. Influence of different culture conditions including varied environmental and nutritional conditions were tested. Lipase activity was determined by colorimetric method based on the activity in cleavage of p-nitrophenylpalmitate (p-NPP). Maximum lipase production (5.1 mM/min) was found on the fifth day of the cultured filtrate at pH 8 and temperature of 30°C. Two point five percent (2.5%) oil concentration supported highest lipase enzyme production with (6.67 mM/min). Ammonium phosphate and glucose encouraged the maximum activity/production. Optimum production of lipase (6.46 mM/mins) was exhibited by medium supplemented when cell growth is 0.286 mg/l. Also, sulphate produced lipase maximally among the non metals used. From this work, optimizing the culturing conditions and modifying the composition of the medium dramatically improved the lipase production by Lysinibacillus sphaericus. Lipase production by Lysinibacillus sphaericus is very promising and could be used for industrial purposes and biotechnology.