Optimization of Lipase Production using Differential Evolution

Differential Evolution (DE) coupled with Response Surface Methodology (RSM) has been used for the optimization of extracellular lipolytic enzyme production by Rhizopus oryzae NRRL 3562 through sold state fermentation. The input space of the experimentally validated RSM-model was optimized using a novel Differential Evolution approach (DE), which works based on the natural selection and survival of the fittest concepts of the biological world. The maximum lipase activity of 96.52 U/gds was observed with the DE stated optimum values of 35.59℃, 1.50, 5.28, and 4.83 days for temperature, liquid to solid ratio, pH, and incubation time respectively. The optimal levels of control parameters namely number of population, generations, crossover operator, and mutation constant were equal to 20, 50, 0.6, and 0.20, respectively. The developed model and its optimization are generic in nature and thus appear to be useful for the design and scale-up of the extracellular lipase production by R. oryzae NRRL 3562 through solid state fermentation.