Production of thermostable beta-amylase and pullulanase by Clostridium thermosulfurogenes SV2 in solid-state fermentation: Screening of nutrients using Plackett-Burman design

Screening of fifteen nutrients belonging to four categories, viz., carbon, nitrogen, salt and complex organic sources was carried out using Plackett-B urman design for the production of thermostable beta-amylase and pullulanas e by Clostridium thermosulfurogenes SV2 in solid-state fermentation (SSF). This design involves screening of up to 'n-1' variables in just 'n' number of experiments. Regression co-efficients and t-values were calculated by su bjecting the experimental data to statistical analysis. Lactose, diammonium hydrogen phosphate, calcium chloride and casein hydrolysate showed higher regression co-efficients in the biomass formation. Among the fifteen nutrie nts screened, based on their performance in terms of product promoting abil ity, availability and cost, magnesium chloride, potato starch, ferrous sulp hate, pearl millet flour and corn steep liquor were identified as most effe ctive and, therefore, selected for inclusion in further optimization studie s.