Identification of a IShewanella halifaxensis/I Strain with Algicidal Effects on Red Tide Dinoflagellate IProrocentrum triestinum/I in Culture

• Published in: Marine drugs 2023-09, Vol.21 (9)
• Main Authors: Cruz-Balladares, Victoria, Avalos, Vladimir, Vera-Villalobos, Hernán, Cameron, Henry, Gonzalez, Leonel, Leyton, Yanett, Riquelme, Carlos
• Format: Article
• Language: English
• Subjects: Control; Dinoflagellates; Environmental aspects; Growth; Identification and classification; Red tide; Shewanella
• ISSN: 1660-3397; 1660-3397
• DOI: 10.3390/md21090501

The dinoflagellate Prorocentrum triestinum 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 Shewanella was identified and evaluated against P. triestinum. The algicidal effects on the dinoflagellate were observed when P. triestinum 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 P. triestinum 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 Shewanella halifaxensis 0YLH as a promising tool for the environmentally friendly biological control of P. triestinum blooms.