拮抗菌株的筛选及其发酵滤液的抑菌活性

Screening of Antagnologic Bacterium Strain and Its Restraint Activity of Ferment Filtrate

为了获得高效饲用益生菌,采用体外筛选培养法,从土壤中筛选出三株具有抑菌活性的菌株,初步鉴定为地衣芽孢杆菌。其中1#菌株对动物肠道中有害菌如金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌均有较强抑制作用,对其性质进行考察结果表明,在30℃,pH7.0,150 r/min的条件下,恒温振荡培养24 h,测其发酵滤液对金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌的抑菌效价分别为2 000 IU/mL1、500 IU/mL、1 500 IU/mL。在以金黄色葡萄球菌作为指示菌的条件下,该菌株发酵滤液具有较强的热稳定性,60℃放置1 h,抑菌活性下降了29%;100℃放置30 min,抑菌活性下降了45%,放置1 h,抑菌活性下降了48%;121℃放置1 h,抑菌活性仍能保持40%;该发酵滤液抑菌作用的最适pH值为7.0,在pH3.0时能保持71%的抑菌活性,在pH11.0时,仍能维持67%的抑菌活性,此发酵滤液对蛋白酶K不敏感,并且蛋白酶K对该发酵滤液的抑菌活性也起一定的促进作用。

To obtain high-effective valuable bacterium, using outer-body culture method, screen out three strains from soil which have antagonistic, thereinto 1^# has strongly restrain effect to Staphylococcus aureus , Bacillius subtilis , Botrytis cinerea , Streptococcus mutans , Escherichia coli , identified it is Bacillus licheniformis. Inspect it＇s character , the consequence showed that at 30℃, pH7. 0, 150 r/min,constant temperature culture 24 h,the antagonistic energy of ferment fitrate is 2 000 IU/ mL,the ferment fitrate has strongly heat stability,when place it at 60℃ about 1 h, the activity will fall 29 %;when place it 30 minutes at 100℃,the activity will fall 45%,while 1 h the activity will fall 48% ;when place it about 1 h at 121℃,the activity will maintain 40% . The optimum pH of the ferment fitrate is 7.0, at pH3.0,it can keep 71% activity , at pHil. 0,it can keep 67% activity,the fer ment fitrate is non-tenderness about protease K,and protease K has auxo-action about the ferment fitrate.