Pigment assemblages in subtropical bloom-forming cyanobacteria strains.

This article focuses on the characterization of pigment assemblages in subtropical cyanobacterial strains to improve chemotaxonomy and remote sensing methods for monitoring cyanobacterial blooms. The study analyzed carotenoid-to-chlorophyll a ratios and in vivo absorption spectra of nine cyanobacterial strains from four taxonomic orders (Synechococcales, Chroococcales, Oscillatoriales, and Nostocales), identifying distinct pigment profiles linked to phylogeny. Notably, Nostocales species, common in warm-climate lake blooms, exhibited high levels of myxoxanthophyll and echinenone but low zeaxanthin, suggesting that pigments other than zeaxanthin should be used as markers for this group. These findings provide valuable data for refining pigment-based algorithms, such as CHEMTAX, to enhance the accuracy of cyanobacterial bloom detection and monitoring in subtropical freshwater ecosystems.