Effect of exogenous supplement on fermentative production of riboflavin by Bacillus subtilis
Taking cell concentration and riboflavin production as the indicator,the effect of seven exogenous supplements on riboflavin production by Bacillus subtilis was investigated based on the analysis of metabolic networks and study of fermentation characteristics.The results showed that the addition of calcium gluconate,sodium citrate and alanine had a significant role in promoting riboflavin fermentation.The influences of their adding time and contents on riboflavin production were demonstrated in a further study.The optimal adding time of calcium gluconate,sodium citrate and alanine were 0h,18h and 18h respectively,and the optimal dosage were 7.5g/L,4g/L and 2g/L respectively.Finally,the best ratio of the three accelerators was determined as 7.5g/L,5g/L and 1.5g/L by the orthogonal experiment.Under optimal conditions,riboflavin yielded up to 6.46 g/L,which increased by about 8％ or by nearly 40％ comparing to that under condition with only one additive or without any additives.
国家科技期刊平台
NSTL
万方数据
维普
