Optimal production of alkaline protease from solvent-tolerant alkalophilic <i style="">Pseudomonas aeruginosa</i> MTCC 7926

Abstract

A new organic solvent-tolerant bacterial strain UD-5 was isolated from industrial solvent effluent-sediment stream, collected from Ankleshwar (India) and documented for the production of solvent-tolerant alkaline protease. Based on phylogenetic analysis of the 16S rRNA gene sequence and phenotypic analysis, as well as biochemical analyses, this strain was identified as <i style="">Pseudomonas aeruginosa</i> MTCC 7926. It secreted an extracellular, thermostable; alkaline protease in a casamino acid-rich salt medium (<i style="">p</i>H 9) at 40°C, in static condition. The solvent-tolerance of bacterium in the presence of <i style="">n</i>-hexane, dodecane, cyclohexane and DMSO, xylene and tolune was analyzed. Effect of <i style="">p</i>H, temperature, agitation, carbon and nitrogen sources and various salts on the growth and protease production by strain UD-5 of solvent-tolerant<i style=""> P. aeruginosa</i> MTCC 7926 from-manmade ecological habitat was studied. It provided an alternative source of alkaline protease with additional attributes of industrial applications compared to proteases reported earlier. Its ability to grow in organic solvents especially in water-miscible solvents (DMF and DMSO) proves its potential for applications in non-aqueous reactions in addition to usage in detergent, laundry additives and leather finishing.