Abstract The effect of volumetric oxygen mass transfer coefficient (KLa) on the biomass and the commercial interest biomolecules production, was studied in the Ganoderma lucidum submerged culture using a low-cost complex medium. The batch culture was carried out in a 14 L stirred tank bioreactor, a KLa initial value set at 5.3 h-1 had a positive effect on exopolysaccharides production, achieving a maximum concentration of 1.15 g/L, under this condition, biomass production was negatively affected. An increase in the KLa initial values between 17.3 32.8 h-1, allowed us to obtain a culture with better oxygen and nutrients transfer conditions. These values improved the kinetic carbohydrate uptake, fungal growth, and enabled the adequate supply of oxygen for a long time, achieving a maximum biomass concentration of 9.8 g/L. Under these conditions, the average production of exopolysaccharides is 0.46 g/L, and crude protein extract production was around 0.3 g/L. The complex medium (made from barley flour) used in this study is a low-cost medium that showed great potential for the replacement of synthetic high-cost media that are conventionally used in Ganoderma lucidum submerged cultures in a stirred tank bioreactor.

Resumen 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.

Abstract Microalgae transform CO2 into a broad portfolio of biomolecules, and thus should be considered as a valuable biotechnological platform. Despite several research programs and global efforts to establish a sustainable microalgae-based industry, most applications have not transcended academic boundaries. This limitation raises from the high transformation costs when target products are biofuels or fertilizers. Microalgae biorefinery emerges as an alternative to improve economic competitiveness, as Under such a model scope, the process inputs come from industrial waste, while biomass exploitation prioritizes the highest value molecules followed by extraction of less valuable compounds. This review describes a wide range of microalgae exploitation schemes focused on new uses of its constituents, while discussing emerging technologies designed to improve production and efficiencies as well.