溶藻细菌的分离及溶藻特性研究

Isolation and Bacteriolysis of Algicidal Bacteria

从爆发蓝藻水华的鱼池采集水样,以铜绿微囊藻为对象进行溶藻细菌筛选,得到R1、R2、R3、R5、R6、R8和R9共7株溶藻细菌,生理生化特征初步鉴定R5为海鱼弧菌,另6株为非发酵型细菌。R1、R3、R5、R8和R9细菌含量为105～108 cfu/ml时,对微囊藻的抑制率很高,效果优于R2和R6。对R1、R3、R5和R9进行溶藻范围测定时,发现这4株菌株对钝顶螺旋藻、小颤藻、水华鱼腥藻的抑制率均高于80%,且R5对小颤藻的抑制率明显高于其他3株菌株,但这4株菌株对斜生栅藻均无抑制作用。毒性试验显示,R5能使鲫鱼致死,其他菌株则无致死作用;溶藻机理试验表明,溶藻作用是细菌的胞外产物作用的结果。

Seven strains（R1,R2,R3,R5,R6,R8 and R9） of algicidal bacteria against harmful algal blooms were isolated from the ponds with cyanobacterial bloom in Chongqin.The R5 strain was identified as Vibrio damsel and the others belonged to nonfermenters by physiological characteristics analysis.The R1,R3,R5,R8 and R9 were showed to have higher inhibitory effects on the growth of Microcystis aeruginosa than R2 and R6 at the density of 105~108 cfu /ml.The R1,R3,R5 and R9 degraded more than 80% of the cells of Microcystis aeruginosa,Spirulina platensi and Anabaena flosaguas within 7 days,and R5 had higher inhibitory effect on Oscillatoria tenuis than R1,R3 and R9 did.No inhibitory effects on Scenedesmus obliqnuus were found among these strains.The toxicity test showed that the strain R5 had lethal to the goldfish.However,no adverse effects when the other strains were injected to the fish.The mechanism of algal cell lysis is considered to be involved in some extracellular products.