Response surface optimization of the substrate concentration and cultivation conditions for the production of mannitol by Leuconostoc fallax Ln92 using whey as cost effective medium

Abstract

The optimization of the cultivation conditions and substrate concentration for mannitol production by a prolific mannitol producing strain Leuconostoc fallax Ln92 was carried out using a 2³ central composite design and surface modeling method of response surface methodology. The response selected for the optimization was mannitol production. The selected factors based on preliminary investigations were fructose concentration, temperature and incubation period. The optimum concentrations of fructose and temperature were found to be 98g/l and 34ºC respectively at 68 h incubation. The optimized conditions resulted in an increase in mannitol production by 30.43% than before optimization.  Using the method of experimental factorial design and response surface analysis, it was possible to determine optimal operating conditions to obtain a higher mannitol production by Ln. fallax. Therefore, present study constitutes a step in developing strategies to increase the mannitol production using whey as a cost effective medium.