短短芽孢杆菌DFG对金黄色葡萄球菌的抑制效果

为短短芽孢杆菌(Brevibacillus brevis)DFG菌株的开发应用提供参考,采用不同化学物质处理方法结合琼脂打孔法研究不同培养基、接种量和发酵时间对其发酵液抑菌活性的影响,并在此基础上研究温度、蛋白酶、酸碱、紫外线照射和反复冻融等因素对其抑菌物质稳定性的影响。结果表明:NA培养基培养的DFG菌株其发酵液对金黄色葡萄球菌(Staphylococcus aureus)的抑制作用最强,抑菌圈直径达2.4cm;发酵液经100℃处理30min,抑菌率仍达65%;对酸碱也具有较强的稳定性;经紫外线照射和反复冻融后性质稳定;对胃蛋白酶、胰蛋白酶及蛋白酶K不敏感,可用有机溶剂对短短芽孢杆菌DFG菌株抑菌物质进行部分萃取。

Antibacterial Effect of Brevibacillus brevis DFG Strain Against Staphylococcus aureus

The effect of different medium, inoculum size and fermentation time on the bacteriostatic activity of B.brevis DFG strain fermentation broth was studied by different chemical treatment and agar punch method and the effect of temperature, protease, pH value, ultraviolet irradiation and repeating freeze thawing on the bacteriostatic stability of B.brevis DFG strain fermentation broth to provide a reference for development and application of B.brevis DFG strain.Results: The fermentation broth of DFG strain cultured in NA medium has the maximum inhibition effect against S.aureus and its bacteriostatic diameter reaches 2.4 cm.The bacteriostatic rate of the fermentation broth treated for 30 min at 100℃ still is up to 65%.The fermentation broth is of strong stability under different pH value.The quality of the fermentation broth after ultraviolet irradiation and repeating freeze thawing is stability.The bacteriostatic substance of B.brevis DFG strain can be partially extracted with organic solvents because B.brevis DFG strain is no sensitive to pepsin, trypsin and protease K.