Optimization of process parameters for enhanced thermostable lipase production by bacillus subtilis SHVSC04.

Abstract

Thermophilic lipases are stable at higher temperatures, which enhance their demand in industrial applications. In the present study, thermostable lipase was produced from bacterial strain Bacillus subtilis SHVSC04 (MN565992) isolated from Tuva Timba hot spring, Gujarat, India. Isolate displayed maximum growth in basal medium augmented with 3% sucrose, 3% yeast extract and 2 % salt at pH 7 and 50°C in 48 h. Whereas, isolate produced maximum lipase in tributyrin agar medium with pH 7, enriched with 3% sucrose, 3% yeast extract and incubated at 50°C in 72 h. Tributyrin (2%) was found to be the best substrate for lipase production in submerged conditions. The amount of lipase was increased by 1.5 fold upon optimization of different environmental and nutritional parameters. The enzyme retained 84% activity at 60°C and 70% of activity at 70°C for 1h. The present findings advocate that hot springs in Gujarat are a substantial source of thermostable bacteria producing enzymes of industrial importance.