Application of algicidal bacteria is a promising
and environmentally friendly way to control cyanobacterial
blooms. Lytic effects of the algicidal bacteria on
Microcystis aeruginosa
have been observed, but the interactions
between algicidal bacteria and the cyanobacteria are still
elusive. An algicidal bacterium
Bacillus
sp. B50 isolated
from Lake Donghu showed a highly lytic efficiency on
M. aeruginosa NIES-843 through heat-resistant extracellular
substances from strain B50. The cell density of strain
B50 could be maintained at high levels during the lytic
process in bacteria–Microcystis system with inoculation
densities of 1.9 x 10
6 and 1.9 x 10
7 cfu/mL, resulting in
the death of
M. aeruginosa NIES-843. However, the population
dynamics of strain B50 was a bell-shaped curve at
low inoculation densities and no lytic effect could be
observed. Results of physiological responses suggested that
the lytic efficiency may be mediated through inhibition of
metabolism and production of reactive oxygen species.