Optimization of Process Parameters for Improved Lipase Production by Hyperthermophilic Bacillus sonorensis 4R

Thermostable lipases isolated from thermophilic bacteria are emerged as industrially and
biotechnologically important bio-molecules in recent era of globalization due to their potential to work
at high temperatures. Knowledge of growth conditions and nutritional parameters controlling lipase
production is necessary to improve its yield and successful development of an industrial bioprocess
without increasing the cost of production. We are reporting the individual and interactive effects of
process parameters on lipase production by a hyperthermo-alkalophilic strain of Bacillus sonorensis
4R. In the present study, the individual and combined effects of process parameters on lipase
production by a hyperthermo-alkalophilic strain of B. sonorensis 4R are studied. Parameters used in
this study were incubation period, temperature, initial pH of medium, carbon and nitrogen sources,
substrates and metal salts. The isolate showed maximum lipase production after 4 days of incubation
at 80°C and pH 8.0 and when growth medium was supplemented with 1% glucose, 1% ammonium
sulphate, 100mmol CaSO4 and by using 1% Tween-80 as lipidic substrate. The combined effects of
six variables (pH, temperature, substrate concentration, carbon source, nitrogen source and metal
salt) studied in 12 experimental sets showed highest lipase production (51.33 U/mL) by B. sonorensis
4R. In a medium design composed with Tween-80 (1%), CaSO4 (100 mmol), glucose (0.5%),
ammonium sulphate (1%), pH (7.5) and when incubated at 80°C, 6.88 fold enhancement over control
was observed in lipase production. In the present study, lipase production from B. sonorensis 4R has
been optimized using individual and combined effects of simple and easily manageable process
parameters. This knowledge will be helpful to many industrial processes to obtain improved enzyme
productivity.