Extracción e Identificación de metabolitos potencialmente tóxicos a partir de Cianobacterias (Oscillatoria sp. y Microcystis sp.)

Abstract

Cyanobacteria or blue-green algae are essential photosynthetic microorganisms in aquatic ecosystems, capable of performing oxygenic photosynthesis and fixing nitrogen, which enhances soil fertility. However, their excessive proliferation can lead to water quality and public health problems due to the production of cyanotoxins that affect both humans and animals. This work aimed to develop a preliminary, accessible, and low-cost method to detect potentially toxic metabolites present in extracts of the cyanobacteria Oscillatoria sp. and Microcystis sp. Thin-layer chromatography (TLC) was applied to qualitatively separate and identify cyclic peptides and alkaloids, using revealing reagents such as 2 % ninhydrin and Dragendorff. Additionally, acute toxicity bioassays were conducted on Daphnia magna to evaluate the biological effect of the extracts. Chromatographic results evidenced the presence of compounds compatible with microcystins and β-carboline alkaloids in Microcystis sp. Toxicity tests showed high mortality at concentrations of 1 mg/mL, especially in extracts obtained with methanol-water. These findings underscore the need for continuous monitoring of cyanobacteria in water bodies, as well as the implementation of management strategies to mitigate the risks associated with their proliferation.