从山东黄岛边某富营养化池塘中分离得到1株具有溶藻作用的菌株(J1),研究了其对铜绿微囊藻(Microcystis aeruginosa)的抑制效果、作用方式以及细菌培养基、菌株与铜绿微囊藻不同生长阶段等因素对溶藻效果的影响,并对该菌株进行了生理生化鉴定.结果表明,将牛肉膏蛋白胨培养基加入藻液,培养基与藻液的投放体积比为6%时,9d内对藻的生长无影响.将初始浓度为6×107cfu/mL的菌液加入藻液,共培养第9d,铜绿微囊藻的去除率达87%以上.对数期的J1细菌具有较好的溶藻效果,作用于稳定期铜绿微囊藻的实验组,藻的去除率较低.J1通过分泌溶藻物质的间接作用方式抑制铜绿微囊藻的生长,且溶藻活性物质具有一定的热稳定性.根据生理生化及16S rDNA序列分析鉴定,菌株J1属于芽胞杆菌属(Bacillus).
An algae-lysing bacterium strain named J1 was isolated from an eutrophic pond around Huangdao.The lytic efficiency and performing mode of bacterial lysing of Microcystis aeruginosa were studied.Influences of the bacterial culture medium and the growth phases of bacterium and algae on the antialgal effect were also studied,and then the bacterium strain was physiologically and biochemically identified.The results showed that algae growth was relatively stable with adding beef-protein medium without bacterium strain when the volume ratio of medium to algae solution was 6%.However,more than 87% of Microcystis aeruginosa had been removed by 9 days after adding the beef-protein medium with initial bacterium concentration of 6×107 cfu/mL under the same volume ratio.The antialgal efficiency was different to the various growth phages of bacterium and algae.J1 in log growth phase showed the best algae-lysing performance.The removal rate of algae in stable phrase was the lowest under the treatment with J1 in log growth phase.J1 excreted algae-lysing substance to inhibit the algae growth indirectly,and this active inhibitors were heat-stable.According to the morphological and physiological-biochemical characteristics,bacterium J1 was identified as Bacillus.