高效铜绿微囊藻溶藻菌WJ6的分离鉴定及溶藻特性

Isolation and identification of an efficient algicidal bacteria strain and algicidal characteristics on Microcystis aeruginosa

以铜绿微囊藻为研究对象,从富营养化水体分离了一株高效溶藻菌,通过分析形态学、生理生化特征及16SrDNA序列比对,鉴定了该溶藻菌株,分析了该菌株对铜绿微囊藻的溶藻方式、溶藻特性及其不同培养时期、不同浓度菌液及不同环境因子对溶藻效果的影响,并探讨了其可能的溶藻机制.研究表明:WJ6属于沙雷氏菌属(Serratia sp. GenBank登录号为KY462187);溶藻菌WJ6以胞外释放溶藻物质为主直接溶藻为辅的溶藻方式;溶藻菌WJ6处于对数期时的溶藻率最高达87.50%;菌液浓度达1.4×10~9CFU/mL以上,溶藻率最高为95.69%;在30℃、pH8条件下,溶藻率达90.00%;改良的基本培养基培养的溶藻菌溶藻率最高达98.50%;铵离子浓度大于2mol/L时,溶藻菌的溶藻率98.33%;当盐度为0.5%时,溶藻率较高为92.77%.溶藻菌株WJ6是1株高效溶铜绿微囊藻菌,在富营养化治理方面具有较好的应用前景.

An algicidal bacteria strain with a strong algicidal effect to M.aeruginosa was isolated from the eutrophic water.Then,the algicidal bacteria was identified as WJ6 by analyzing it’s morphological features,physiological and biochemical characteristics,as well as phylogenetic analysis of 16S rDNA sequences.The algae-lysing means of WJ6 and the effects of different culture periods,concentrations of bacterium and environmental factors on the algae-lysing action were investigated to analyze the algicidal characteristics and possible algae-lysing mechanism of the strain WJ6.And the results showed that WJ6 was identified as Serratia sp.(Accession No.KY462187).The algicidal mechanism of WJ6 is indirectively,which disolves the algae mainly by an extracellular products.At logarithmic growth phase,the strain WJ6 can dissolve M.aeruginosa with a removal rate of 87.50%.The bacteria WJ6with on centration more than 1.4×109CFU/mL can give the highest removal rate of 95.69%.Under the condition of 30℃and pH8,the removal rate is 90.00%.The effect of modified basic mediumon the algae-lysing effect of WJ6 is the most obvious with the higests removal rate of 98.50%.Furthermore,the removal rate of the algicidal bacterium is 98.33%when the ammonium ion concentration in the mediumis above 2mol/L.The removal rate is 92.77%when the salinity is 0.5%.All the results stated above indicate that the algicidal bacteria strain WJ6 have a strong algicidal effect to M.aeruginosa and prospective application in the control of M.aeruginosa in eutrophic water.