Plackett-Burman design for screening of fermentation process parameters and their effects on L-methionine production

Abstract

Plackett-Burman design for L-methionine production Abstract In the present study, economical fermentation medium process was developed to achieve the maximum production of L-methionine by Corynebacterium glutamicum through screening of different nutritional and physical parameters by Plackett-Burman design. A total of eleven process variables such as plantain as carbon source, groundnut as nitrogen source, CaCO3, K2HPO4, KH2PO4, biotin, MgSO4.7H2O, inoculum size, agitation speed, volume ratio of medium/fermenter and pH were used for screening experiments. The PBD model results suggested that seven variables namely plantain as carbon source, groundnut as nitrogen source, CaCO3, MgSO4.7H2O and KH2PO4 had shown a significant effect on L-methionine production, while remaining six variables didn’t show a much effect on Lmethionine production. The R2 value (0.99) of analysis of variance (ANOVA) recommended that the model used for response prediction is significant (p<0.05). In comparison with the unoptimized medium, 24% higher L-methionine production was obtained from the optimized medium and L-methionine production was found to be 5.6 g/l.