Process development for the enhanced production of bio-nematicide Purpureocillium lilacinum KU8 under solid-state fermentation.

Response surface methodology (RSM) was used to optimize the process parameters for maximizing the biomass production of Purpureocillium lilacinum KU8 using wheat bran as substrate under solid-state fermentation (SSF). The experiments of one-factor-at-a-time approach (OFAT) for central composite design (CCD) to analyze the response pattern brought out the parameters for maximum biomass production. Moisture content, yeast extract and incubation time were found to be the three significant, independent variables responsible for maximum biomass production. The biomass production was 107.46 mg/gdfs which was 1.35 times higher than that of OFAT method and 3.01 times higher than the randomly selected conditions. The optimum conditions established by RSM method for the maximum biomass production are 67.98%, 2.29% and 142.2 h respectively for moisture content, yeast extract and incubation time. The biomass thus produced had quantitatively comparable results in bio-nematicide effectiveness.