Las microalgas transforman el CO2 en un amplio portafolio de biomoléculas, por lo cual, son consideradas una valiosa plataforma biotecnológica. A pesar de múltiples programas de investigación y esfuerzos globales para establecer una industria sostenible basada en microalgas, la mayoría de las aplicaciones potenciales no han trascendido las fronteras académicas. Esta limitación se debe a los altos costos en la transformación del producto principalmente cuando se obtiene compuestos económicos como biocombustibles y fertilizantes. La biorefinería de microalgas surge como alternativa para incrementar la competitividad económica. En este modelo, los insumos del proceso provienen de residuos industriales, mientras que la explotación de la biomasa inicia con las moléculas de alto valor y finaliza con los compuestos menos valiosos. En esta revisión se describe un amplio abanico de esquemas de explotación de microalgas enfocado en nuevos usos de sus constituyentes. Además, se exploran las tecnologías emergentes destinadas a aprovechar esta biomasa de una manera más versátil y eficiente.
In this study the metabolic responses of Botryococcus braunii were analyzed upon different inorganic carbon dosages and nutrient limitation conditions in terms of lipid and biomass productivity, as well as photosynthetic performance. The nutritional schemes evaluated included different levels of sodium bicarbonate and nitrogen and phosphorus starvation, which were contrasted against standard cultures fed with CO2. Bicarbonate was found to be an advantageous carbon source since high dosages caused a significant increase in biomass and lipid productivity, in addition to an enhanced photosynthetic quantum yield and neutral lipids abundance. This contrasts to the commonly used approach of microalgae nutrient limitation, which leads to high lipid accumulation at the expense of impaired cellular growth, causing a decline in overall lipid productivity. The lipidome analysis served to hypothesize about the influence of the nutritional context on B. braunii structural and storage lipid metabolism, besides the adaptive responses exhibited by cells that underwent nutrient stress.
There are several strategies to improve the growth of microalgae in industrial processes. In recent years, one of them has gained strength to achieve this goal: the co-culture with bacteria. Using growth-promoting substances, producer bacteria enhance microalgae biology activity, similar to how they have been used to promote the successful production of crops. The aim of this study was to evaluate the promoter capacity of strains Bacillus subtilis, Corynebacterium aquatile and Flavobacterium aquatile, evaluate their ability to improve the growth rate of microalgae Botryococcus braunii and to optimize the process derived from its cultivation. This study showed that the tested bacteria were able to increase up to 1.7 times the B. braunii growth rate and this promoting ability remained present in cell lysate preparations from the same bacterial strains.