Screening and Optimization of Industrial Medium for Mass Production of Candida membranifaciens, Biocontrol Agent of Blue Mold and Gray Mold Diseases of Apple

The optimization of nutrient factors in mass production of biological agents is one of the most important processes in trade and industry development. In this study، response surface methodology (RSM) has been used to increase cell biomass production of Candida membanifaciens by optimizing medium components during two steps; screen of medium culture composition and evaluation of process factors. Sugar beet molasses، cane molasses، permit powder and sucrose used as carbon sources while corn step liquor، urea and yeast extract were used as nitrogen source. Different sources of carbon and nitrogen were studied by Design- Expert software. Results exhibited that sugar cane molasses and CSL have significant effect on biomass production of the yeast. Based on analysis of variance (ANOVA)، a quadratic polynomial model with its interactions was found to be best model for determining yeast growth. According to growth equation as well as analyzing response surface plots، the optimal concentrations of sugar cane molasses and CSL in the medium were determined 20 g/l and 39. 2 g/l respectively.