Beyond monoculture limits: a critical review of yeast co-cultures for xylitol production from lignocellulosic biomass : Yeast co-cultures for xylitol production.

The biotechnological production of xylitol from lignocellulosic biomass residues offers a sustainable alternative to traditional chemical synthesis; however, its industrial implementation is limited by the metabolic constraints of conventional microbial monocultures. This review examines the limitations of monocultures, highlighting how redox cofactor imbalances, glucose-induced catabolic repression, and the toxicity of furanic inhibitors and organic acids in crude hydrolysates create energetic and metabolic challenges that reduce yields and volumetric productivity. To overcome these biological limitations, it is necessary to shift toward co-culture engineering based on the principle of division of labor (DoL). Key synergistic mechanisms, including in situ detoxification, parallel utilization of pentose and hexose mixtures, and metabolite exchange (cross-feeding), which distribute metabolic functions among specialized strains, expanding metabolic diversity and optimizing carbon valorization, are analyzed. Implementing control strategies that maintain coordinated fluxes is critical to positioning consortia as a viable and profitable platform for xylitol production.