解淀粉芽孢杆菌Q-12抗真菌特性的研究

Antifungal Characterization of Bacillus amyloliquefaciens Q-12

从土壤中分离到的解淀粉芽孢杆菌Q-12在生长过程中产生的抗菌活性物质,能够强烈抑制镰刀菌、曲霉、青霉、毛霉等能引起食品腐败的真菌。受到抑制的真菌菌丝生长速度明显变慢,并且菌丝的形态发生变化。Q-12的发酵液经过(NH4)2SO4沉淀得到的粗提产物对热稳定,121℃高压灭菌15 min仍能保持很高的活性,易溶于水及极性有机溶剂,经非极性有机溶剂萃取后,保留在水相的活性物质活性变化不大,在较宽的pH值范围内都具有很高的抗菌活性,并且对蛋白酶K、胃蛋白酶、木瓜蛋白酶不敏感。

Bacillus amyloliquefaciens Q-12 isolated from the soil can strongly inhibit mycelial growth of many species of Fusarium oxysporum, Aspergillus sp., Paecilomyceswas sp. and Mucor sp. The strains were also found strongly inhibiting the growth of Fusarium hypha and the germination of its spores. Its metabolites were heat-stable and remained active after sterilization at 121 ℃ for 15 min. Their activities were stable over a wide range of pH. The crude precipitate of the metabolites obtained by ammonium sulphate precipitation were soluble in water and relatively polar organic solvents, and were resistant to hydrolysis by various proteases such as protease K, pepsin and papain.