Optimizing Production of Pectinase from Orange Peel by Penicillium oxalicum PJ02 Using Response Surface Methodology

A novel strain Penicillium oxalicum PJ02 was isolated for the production of exo-pectinase, endo-pectinase, carboxymethylcellulase (CMCase) and xylanase. Response surface methodology (RSM) was employed to optimize orange peel submerged fermentation for pectinase production. Plackett-Burman factorial design was used to select significant parameters. Temperature and NH4Cl concentration had significant influence on exo-pectinase production. The central composite design was used to generate a total of 22 fermentation experiments. The statistical results indicated that the optimum temperature for exo-pectinase and endo-pectinase production was 36.5 degrees C, and optimal NH4Cl concentration was 1.12 g/L. Under this condition, the yield of exo-pectinase was 36.88 U/mL, endo-pectinase was 0.62 U/mL, which are in close agreement with the values predicted by the model. The CMCase and xylanase yield in the same medium were 0.38 and 0.57 U/mL, respectively. RSM was also used to analyse the effect of independent variables on CMCase and xylanase production.