Isolamento, cultivo e taxonomia de cianobactérias de ambientes aquáticos urbanos de Macapá

Abstract

This study aimed to isolate and morphometrically characterize cyanobacteria species present in the main water bodies of the municipality of Macapá, in order to contribute to the understanding of regional aquatic biodiversity and its biotechnological potential. Sampling was carried out at three sites—Balneário do Curiaú, Canal do Jandiá, and Museu Sacaca—in December 2024, using a 20 μm plankton net haul, raw water collection, and measurement of environmental parameters (pH, temperature, and transparency). Isolation was performed using the micropipette isolation technique, followed by morphological characterization under both light and inverted microscopes, supported by taxonomic descriptions and identification keys. The samples were cultured in BG11, BG11-0, and an alternative medium. A total of nine strains were obtained from seven isolated or semi-isolated taxa: Coelosphaerium kuetzingianum, Microcystis panniformis, Geitlerinema splendidum, Microchaete sp., Dulcicalothrix alborzica, Cephalothrix lacustris, and Nostoc sp. The taxa were classified into four taxonomic orders: Chroococcales, Geitlerinematales, Nostocales, and Oscillatoriales. Some species, such as Dulcicalothrix alborzica, Microchaete sp., and M. panniformis, were recorded for the first time in water bodies of Amapá. The results highlight the importance of continuous studies on Amazonian cyanobacterial biodiversity, emphasizing the need for complementary molecular analyses to confirm taxonomic identification, detect new species, and assess the biotechnological and toxicological potential of the isolates. This work contributes to the expansion of the scientific knowledge base in the state of Amapá and provides relevant support for environmental monitoring and management in the region.