富贵竹黑腐病拮抗菌H5的抑菌机制及相关特性研究

从湛江红树植物-红海榄筛选出1株对引起富贵竹病害黑曲霉病菌(Aspergillus niger)有良好抑制作用的菌株编号为H5,初步鉴定为地衣芽孢杆(Bacillus licheniformis).该菌株采用平板对峙、生长速率法及菅碟法对黑曲霉均表现良好的抑制作用,发酵原液对茵丝生长和孢子萌发的抑制率分别为91.9%和100%,抑菌带内菌丝扭曲畸形、表面产生大量囊状突起.其无菌滤液对酸碱、热稳定性较好,经55%硫酸铵沉淀后经121℃处理25 min仍能保持大部分活性,初步推测该物质为一种耐热的蛋白.

Antagonistic Mechanisms and Related Properties of Strain H5 Against Black-rot Disease of Dracaena sanderiana

A strain no. H5 isolated from Rhizophora stylosa Griff in Zhanjiang had a good antagonistic activity against Aspergillus niger, pathogen of Dracaena Sanderiana black-rot disease. It was identified as Bacillus licheniformis. Dual culture, mycelium growth rate and inhibitory zones were used to test the effect. Strong inhibition was shown against A. niger. Inhibitory ratios of H5 germ-free fermented filtrate on mycelium growth and conidial germination were 91.9% and 100% respectively. In addition, mycelia on the edge of antagonistic band became abnormal and over-branching. Meanwhile, a lot of vesicles appeared on the surface. When treated with heat, acid and alkali, the filtration of H5 was always with stable activity. Precipitate in 55% saturated ammonium sulfate dissolved in phosphate buffer solution maintained most of the activity after high pressure steam sterilization for 25 minutes. It was preliminarily considered as a kind of heat resistant protein.