三株溶藻细菌胞外溶藻活性物质若干分离特性的研究

Research on Separation Characteristics of the Extracellular Algae-lysing Components from Three Algae-lysing Bacteria

为了探索新分离到的3株溶藻细菌胞外溶藻活性物质的分离特性,选择了对水华鱼腥藻生长无抑制作用的淀粉培养基培养溶藻细菌。采用透析、乙醇沉淀、有机溶剂萃取、活性炭吸附与解吸等方法对其分离特性进行了研究。溶藻细菌L7的溶藻活性物质的分子量小于3.5kD,溶藻细菌L8、L18的溶藻活性物质的分子量在3.5kD～7kD之间;3株溶藻细菌的胞外溶藻活性物质不能用乙醇沉淀法完全分离;3株溶藻细菌的溶藻活性物质具较好的亲水性和较强的极性,且都不能被活性炭吸附。

Three algae-lysing bacteria （L7, L8, L18） have been isolated. We used starch medium, which has no passive effect on growth of the Anabaenaflos-aquae as cutivate medium. After being cultivated for 4d on a reciprocal shaker at 30℃ and a speed of 100 r/min, the cultivate broth were centrifugated at a speed of 4000 r/min for 20min, filtrated with 0.22 μm membrane, and condensed by vacuum rotary evaporator at 65℃. The sterile condensed bacteria-free filtrate obtained are dialysed, sedimentated by ethanol, extracted by organic solvents, absorbed by activated carbon, The molecular weight of the extracellular algae-lysing components of L7 are less than 3,5 kD, while the molecular weight of extracellular algae-lysing components of L8 and L18 are between 3.5 kD-7 kD; ethanol can not separate extracellular algae-lysing components from other componets efficiently; carbon tetrachloride can separate the extracellular algae-lysing components of L7 into water-layer efficiently, while petroleum ether can separate the extracellular algae-lysing components of L8 and L18 into water-layer efficiently, the extracellular algae-lysing