Long-term fermentation by microalgae-yeast consortium efficiently converts volatile fatty acids from a real wastes stream into microbial oils

Abstract

The present research describes the long-term fermentation of a microalgae-yeast consortium using volatile fatty acids (VFAs) supplied from a real anaerobic fermentation (AF) waste stream, enabling their efficient conversion into lipid and protein production. In addition, the macromolecular composition of the produced microbial biomass in terms of fatty acid (FAs) and amino acid (AAs) profiles highlighting its potential for diverse applications. The microbial consortium formulated by Chlorella vulgaris and Yarrowia lipolytica depicted a high lipid content of a 50.7 ± 2.5% w/w, followed by a 35.5 ± 1.1% w/w of proteins and 13.8 ± 2.0% w/w of carbohydrates. The lipids profile showed the predominance of even chain length acids (C16 and C18). In terms of AAs profile, glutamic acid was the most abundant (13.0 ± 0.1% w/w of volatile solids). This research does not only evidence long term operation feasibility but also provides an in-depth characterization of FAs and AAs profiles of this innovative microbial consortium. These data enable the rational matching of biomass-derived components with specific conversion pathways and end-use requirements, thereby maximizing their value and suitability for targeted bio-based industrial applications.