Caracterización morfológica y evaluación del potencial bioenergético de bacterias provenientes de sedimentos de las lagunas de origen volcánico Quilotoa y Amarilla

Abstract

Currently, energy production and its impact on the environment are really important issues. To face this challenge, the research was focused on the morphological characterization and evaluation of the bioenergetic potential of bacteria found in the sediments of Quilotoa and Amarilla lagoons, which have a volcanic origin. Sediment samples were collected from both lagoons and the physicochemical analyses were performed both, on site and in the laboratory. Then, isolation and phenotypic characterization tests were carried out by inoculating bacterial strains. Microbial combustion cells were created, the material was sterilized and the carbon fiber was treated to evaluate the bioenergetic potential of the microorganisms through microbial fuel cells. The results revealed significant differences in the physicochemical characteristics of the sediments for both lagoons. The Quilotoa lagoon showed a greater diversity of shades and textures in sediments compared to the Amarilla lagoon, which presented dark and coarse sediments. In addition, the phenotypic analysis highlighted the presence of extremophilic microorganisms which are adapted to different temperatures in both lagoons, with significant bacterial diversity and unique bacteria identified in each one. Regarding the bioenergetic potential, the cells with mixed culture from the Quilotoa lagoon reached a higher voltage value (0.505 V), compared to the cells from the Amarilla lagoon (0.295 V). These differences in voltage values suggest a superior bioenergetic performance of the bacteria from the Quilotoa lagoon. The results highlight the relevance of the origin of the bacterial inoculum in the generation of electrical energy in microbial fuel cells and emphasize the potential of the bacteria identified in the sediments of both lagoons as energy producing agents.