Alga-lysing properties of Bacillus sp.

Abstract

Cyanobacterial blooms become a serious environmental threat to the freshwater ecosystem, and several physical and chemical methods have been developed for controlling the blooms. In order to develop a biocontrol agents for controlling the blooms, we carried out screening of the alga-lysing bacteria among the genus Bacillus. The alga-lysing characteristics bacteria isolated from various sources have been studied.Six strains of Bacillus: B.0.2.2.2., 57D, M2, M2a, 10.1, M18Г, with strong algicidal activity against the species of Anabaena hassalii, Microcystis aeruginosa, M. рulvereae were selected. Wide algicidal activity ranged from 40 to 60 % was shown. It was established that the studied Bacillus strains did not possess marked lytic activity against Chlorella spp. and their activity did not reach beyond 15 %. Thus, investigated bacterial strains of the Bacillus genus have algicidal effect towards cyanobacteria and do not such effect towards green algae. The lytic effect of different parts of the bacterial cultures indicated that the algal cells were lysed by the algicidal active compounds in cell-free filtrate. Our results suggest that the studied strains of Bacillus sp. may have a potential for a use in controling growth of harmful algal species.

Keywords

• algicidal activity
• Bacillus sp.
• cyanobacteria