Aislamiento, identificación y evaluación del potencial generador de biocombustibles de desmodesmus communis procedente de la reserva biológica Limoncocha

Abstract

The rapid growth of the population is directly proportional to the energy demand for certain fossil fuels and the environmental problems arising from the use of fossil fuels, cause a strong interest in developing alternatives and clean energy sources, such as third-generation biofuels, which can be produced from renewable raw materials such as biomass, which is one of the most sustainable alternatives. The lipid-producing capacity of some species of microalgae makes these microorganisms arouse great interest as a raw material for sustainable energy production. In this study, the microalgae Desmodesmus communis was isolated from water samples from the lagoon of the Limoncocha Biological Reserve (RBL). Morphological identification was carried out through bibliographic comparisons and molecular identification with PCR using molecular barcodes and with the construction of phylogenetic trees based on the ITS and 18S regions. A ten-day batch culture was carried out using BG11 medium, in which the removal of nutrients was determined daily, at the end of the culture period, the final biomass concentration was 2.4 ± 0.12 g/L. Subsequently, the percentage of lipids and free fatty acids (FFA) were evaluated with the solvents chloroform: methanol (1:2) and ethyl acetate; the best extraction percentages were 19.70% of lipids and 63.46% of FFA, both using dry biomass and chloroform: methanol (1:2) as solvent. These results suggest a better lipid extraction of these microalgae with chloroform: methanol (1:2) compared to ethyl acetate. Despite the fact that the results of lipids and FFA did not reach the required limits, the possibility of using this specie for obtaining biofuels is not ruled out, so more studies are needed.