Identification of a Strain with Algicidal Effects on Red Tide Dinoflagellate in Culture.

The dinoflagellate forms high biomass blooms that discolor the water (red tides), which may pose a serious threat to marine fauna and aquaculture exploitations. In this study, the algicidal effect of a bacterial strain (0YLH) belonging to the genus was identified and evaluated against . The algicidal effects on the dinoflagellate were observed when was exposed to cell-free supernatant (CFS) from stationary-phase cultures of the 0YLH strain. After 24 h exposure, a remarkable reduction in the photosynthetic efficiency of was achieved (55.9%), suggesting the presence of extracellular bioactive compounds produced by the bacteria with algicidal activity. Furthermore, the CFS exhibited stability and maintained its activity across a wide range of temperatures (20-120 °C) and pH values (3-11). These findings highlight the algicidal potential of the bacterium 0YLH as a promising tool for the environmentally friendly biological control of blooms.