Abstract: The effect of fengycin produced by Bacillus subtilis fmbJ on the respiration, mitochondrial NADH dehydrogenase activity, succinic dehydrogenase and nutrients utilization of Rhizopus stolonifer was studied in this paper. The results showed that fengycin mainly restrained the hexose monophosphate pathway. With the increase of fengycin concentration, the activity of NADH dehydrogenase was decreased in vivo, while kept stable in vitro. Both in vivo and in vitro, the activity of succinic dehydrogenase stepped down first and then went up with fengycin concentration. Furthermore, fengycin had an important impact on the utilization of carbohydrates and protein as well as protein synthesis in R. stolonifer. Therefore, fengycin could inhibit the respiratory metabolism and break the balance between anabolism and catabolism in R. stolonifer, subsequently inducing the pathological changes and growth inhibition.

Key words: Bacillus subtilis fmbJ, Rhizopus stolonife, fengycin, respiratory chain, nutrients utilization