溶藻细菌H5对汉斯冠盘藻的溶藻特性研究

摘要

To explore the algicidal characteristic of the algae-lysing bacterium H5 and identified as Lysinibacillus fusiformis,the properties of the algicidal substances in H5 were discussed by methods of dialysis,ethanol precipitation,organic solvent extraction,acid stability analysis.The results showed that the relative molecular weight of the algicidal substances in H5 was 3.5～7.0 ku.The algicidal substances could not be completely separated by ethanol,was hydrophilic higher and had strong algicidal activity under acid conditions with pH 4～7.After addition of bacteria-free filtrate of H5,MDA content of Stephanodiscus hantzschii increased; and the SOD activity sharply increased in 0～196 h and then decreased,indicating the algicidal substances of H5 could lead to the lipid peroxidation of the algae cells,so as to destroy the integrity of the membrane.%为了进一步研究溶藻细菌H5的溶藻特性,采用透析、乙醇沉淀、有机溶剂萃取、酸碱稳定性分析等方法探讨了H5溶藻活性物质的特性.结果表明,H5的溶藻活性物质的相对分子质量在3.5～7.0 ku之间,不能用乙醇沉淀法完全分离,具有较好的亲水性,在pH 4～7的酸性范围内溶藻能力较强.H5无菌滤液使汉斯冠盘藻(Stephanodiscus hantzschii)藻细胞丙二醛含量显著上升,SOD活力在处理0～196 h内急剧上升,随后下降,由此推测该活性物质能使藻细胞发生膜脂过氧化,从而破坏了膜的完整性.