High-throughput screening of acetogenic strains for growth and metabolite profiles on readily available biomass

Bioresour Technol. 2025 Jan 2:419:132026. doi: 10.1016/j.biortech.2024.132026. Online ahead of print.

Abstract

Abundant biomass, including industrial waste streams and second-generation (2G) and third-generation (3G) feedstocks, offers significant potential for sustainable bioconversion, nevertheless challenges such as fermentation inhibitors, CO2 losses and substrate selectivity of traditional microbial hosts hinder process efficiency. In this study, we address these challenges by exploring acetogenic bacteria as alternative microbial hosts. Using a newly established high-throughput method, acetogens were evaluated for their capacity to hydrolyse and metabolize variety of substrates derived from 2G and 3G feedstocks and industrial waste streams. Our findings demonstrate metabolic versatility of acetogens in converting biomass-derived substrates into a wide array of products while also exhibiting resilience to common fermentation inhibitors. These unique capabilities position acetogens as promising alternatives that could potentially outperform conventional production hosts in achieving 100% biomass valorization while underscoring the need for further research into critical areas, such as the utilization of mixed substrates under industrially relevant conditions.

Keywords: Acetogenic fermentation; Biomass valorization; Carbon circularity; Fermentation inhibitors; Hydrolysate fermentation.