黑曲霉菌丝体及发酵液抗菌活性初步研究

Primary study on antibacterial activity of Aspergillus niger mycelia and fermentation broth

对黑曲霉(Aspergillus niger xj)抗菌活性进行研究以筛选天然抗菌药物。利用PDA液体发酵培养黑曲霉,菌丝体用90%乙醇加热回流提取,减压回收溶剂得浸膏,浸膏用水分散,依次用石油醚和醋酸乙酯萃取,分别回收溶剂得到石油醚、醋酸乙酯和水部分。另设发酵液直接用石油醚和醋酸乙酯萃取,分别回收溶剂得到石油醚、醋酸乙酯和水部分。采用滤纸片扩散法对得到的粗提物进行抗菌活性测定。结果表明,在供试浓度为50 mg/mL、指示菌为金黄色葡萄球菌的检测条件下,发酵液醋酸乙酯部分具有明显的抗菌活性,菌丝体及发酵液石油醚部分的抗菌活性相对较弱,其余粗提物未检测到抗菌活性。

In order to develop natural antibacterial agents, the antibacterial activity of Aspergillus niger xj was investigated. After being cultured in PDA liquid medium, mycelia was under heating reflux extraction with 90% ethanol （EtOH）. Removal of EtOH under reduced pressure gave a residue, to which water was added and then extracted with petroleum ether （P.E） and ethyl acetate （EtOAc）. In vacuo evaporation of the solvents yielded three crude extracts. The fermentation broth was directly extracted by P.E and EtOAc. In vacuo evaporation of the solvents also yielded three crude extracts. Then the the disc diffusion method was used to measure the antibacterial activity of these extracts. Results showed that at the concentration of 50 mg/mL, the ethyl acetate extract of fermentation broth exhibited apparent inhibitory effect against Staphylococcus aureus, while the petroleum ether extracts of mycelia and fermentation broth showed moderate antibacterial activity, but the rest were not.