Isolation, identification of algicidal bacteria and contrastive study on algicidal properties against Microcystis aeruginosa

Harmful algae blooms caused by eutrophication have become a global problem. Using algicidal bacteria to control harmful algae is a promising aquatic ecological remediation technology. This study screened two algicidal strains from the environment (YZ1 and CBS), identified as Bacillus sp. and Brevibacillus sp., respectively. A contrastive study on algicidal properties against Microcystis aeruginosa with two preferred algicidal strains, Paenibacillus polymyxa (GDMCC 1.467) and Paenibacillus alvei (GDMCC 1.867), showed that the algicidal activity showed interspecific dependence (GDMCC 1.467>CBS>GDMCC 1.867>YZ1), and the algicidal ratio of GDMCC 1.467, CBS, and GDMCC1.867 were all over 90% within 5 days with 10% bacterial suspension. The algicidal mode of these four strains all belonged to an indirect way. The algicidal substances of YZ1 and CBS showed stability to protease, acid, base, and heat, stronger than those of GDMCC 1.467 and GDMCC 1.867. Brevibacillus sp. showed potential to treat eutrophic water with harmful algae based on its significant algicidal activity and strong stability.