1株巢湖高效溶藻菌的分离鉴定及其溶藻特性研究

Isolation,Identification and Algicidal Characteristics of an Efficient-algicidal Bacterium from Lake Chaohu

对巢湖水华期可分离纯化的菌株进行溶藻菌的筛选、溶藻特性研究和生物学鉴定。筛选出一批有明显溶藻作用的细菌,以3种蓝藻为研究对象,通过叶绿素a的测定,对其中5株溶藻菌的溶藻效率进行比较后,确定了1株高效溶藻菌C1138。通过将菌液经过4种处理(菌液、洗脱菌体、无菌滤液及加热滤液)后与蓝藻混合培养,确定溶藻作用方式。同时,初步探讨了菌液藻液浓度比例对溶藻效果的影响。最后对菌株C1138进行了分子生物学鉴定和PHB染色。结果显示:C1138菌株为Chitinimonas viridis,且PHB染色阳性。菌株C1138对3种蓝藻(FACHB-905、PCC 7806、FACHB-7942)均有显著的溶藻作用,溶藻效率均>50%,且主要通过菌体的直接作用产生溶藻效果,菌株C1138菌体悬液以2/30的体积比加入铜绿微囊藻FACHB-905藻液的效果最佳,且第4天溶藻率达80%以上。

Bacterial strains sampled from Chaohu Lake during the algal bloom period were separated and purified conducting screening,researching and biological identification of algicidal bacteria for the purpose of screening out a group of bacteria that possess efficient algicidal effects.In this laboratory study,three kinds of cyanobacteria were selected as research object and comparison was made for the algicidal efficiency of five strains of algicidal bacteria,and then a highly efficient algicidal bacterium C1138 was determined through the determination of chlorophyll a.Thereafter,solution of this bacterium underwent four treatments of bacteria liquid,thallus elution,sterile filtrate and filtrate heating and then was mixed with cyanobacteria to go through culturing in order to determine the algicidal mode.At the same time,the algicidal effect of the concentration ratio between bacterial and algae liquid on the algicidal effect was discussed preliminarily.Finally,bacterial strain C1138 was molecularly identified and PHB stained,which suggested that C1138 strain was Chitinimonas viridis,PHB staining being positive.In summary,the algicidal effects of strain C1138 were remarkably on three species of cyanobacteria（FACHB-905,PCC7806 and FACHB-7942） with the algicidal efficiency being over 50%;the algicidal effects were mainly generated by the direct action of thallus;and thallus suspension of strain C1138 reached top efficacy when the liquid of Microcystis aeruginosa FACHB-905 was added with a volume ratio 2/30,furthermore,its algicidal rate reached more than 80% on the fourth day.