<i>Ashbya gossypii</i> : From Riboflavin Workhorse to a Next-Generation Cell Factory

Ashbya gossypii is a filamentous hemiascomycete of biotechnological relevance due to its natural capacity for riboflavin overproduction, enabling the replacement of chemical synthesis with a sustainable industrial bioprocess. Advances in genetic and genomic engineering have expanded metabolic engineering tools for further optimization of industrial strains. Consequently, over the past two decades, the bioproduct repertoire of engineered A. gossypii strains has also largely extended beyond riboflavin to include folates, microbial oils, flavor compounds, and aromas, demonstrating notable metabolic plasticity. Remarkably, the ability of engineered strains to efficiently utilize low-cost substrates supports the development of economically viable and sustainable bioprocesses. This review summarizes these advances and highlights future opportunities for the development of novel A. gossypii bioprocessing, to fully exploit its potential as a flexible platform for bioeconomy-driven biomanufacturing.