Recent advancements in Deep Eutectic Solvent (DES) pretreatment: Applications, mechanisms, and integration with emerging technologies for biorefinery

Biomass, with its inherently resilient structure, demands efficient pretreatment as a pivotal step to enable the bioconversion of its components into bioenergy—a vital objective in addressing the current fossil energy crisis. This review examines traditional pretreatment approaches and emphasizes the transformative potential of deep eutectic solvents (DES) in lignocellulosic biomass pretreatment. Beginning with an introduction to various DES types, we explore the mechanisms underlying lignin removal, the production of valuable derivatives, and the feasibility of recycling DES materials. We conclude with a discussion of the opportunities and challenges ahead in refining DES pretreatment for bioenergy applications, highlighting the promising roles of artificial intelligence and synthetic biology in advancing DES-based biorefining systems. This review highlights the transformative potential of deep eutectic solvents (DES) in the pretreatment of lignocellulosic biomass. Additionally, emerging technologies such as enzyme engineering, artificial intelligence, computational biology, and synthetic biology present significant opportunities to advance DES-based biorefinery systems. • A comprehensive summary of various DES categories and their physicochemical properties was presented. • The integration of single and multicomponent DES with advanced pretreatment techniques, such as microwave, ultrasound, hydrothermal, and Lewis acid treatments, opens new possibilities for DES-based pretreatment processes. • Valuable products derived from DES pretreatment and the recovery and reuse of DES after biomass pretreatment were highlighted. • Emerging technologies in enzyme engineering, artificial intelligence, computational biology, and synthetic biology offer significant potential to enhance DES-based biorefinery systems.