培养基组成对贝莱斯芽孢杆菌产抑真菌成分的影响

Bacillus velezensis can produce different kinds of antifungal proteins and lipopeptides at the same time. The specific composition and the content of each component in the culture of B. velezensis were greatly influenced by the composition of the medium. In order to obtain the optimal conditions for the production of antifungal components, the effects of different medium compositions and cultivation times on the antifungal activity and components of B. velezensis fermentation broth were investigated, using Aspergillus niger as a pathogenic fungus indicator. As results, the composition of the medium had a significant effect on the total yield and composition of the antifungal components. Landy medium was found to be more beneficial to cell growth, while NB medium was more beneficial to the production of antifungal compounds. The beef extract benefited the production of antifungal compounds, while peptone did not. The produced antifungal compounds were mainly proteins in Landy medium, while those were mainly lipopeptides in NB medium. The optimal medium composition for the accumulation of overall antifungal components were 20 g/L glucose, 5 g/L sodium chloride, 15 g/L beef extract, 5 g/L sodium glutamate, 20 g/L KH₂PO₄, 10 g/L MgSO₄· 7H₂O, 10 g/L KCl, 3 mg/L FeSO₄, 100 mg/L MnSO₄, and 3. 2 mg/L CuSO₄. This condition improved the cell growth by 75. 9% compared with that of the Landy medium and increased the overall antifungal activity by 21. 9% than that of the NB medium, and the proportion of lipopeptide was higher.