Scale up of dextran production from a mutant of Pediococcus pentosaceus (SPAm) using optimized medium in a bioreactor

the mutant of pediococcus pentosaceus (spam) produced earlier by uv-mutagenesis exhibiting higher dextransucrase activity as compared to wild-type was used. the generated mutant spam gave 12.2 mg/ml, a 20% higher dextran than wild-type. response surface methodology was carried out for further enhancement of dextran production. to enhance dextran production by the mutant spam, plackett-burman design and a 22 full factorial central composite design was employed. after response optimization, the optimum concentration of sucrose and yeast extract was 5.115% (w/v) and 0.635% (w/v), respectively. the experimental values of dextran 36.0 mg/ml at flask level and 35.0 mg/ml at bioreactor level were in good agreement with the predicted value of 40.8 mg/ml. the increase in dextran production by the mutant spam using the optimized medium was 3 fold higher as compared to unoptimized medium.