Abstract: As an abundant biomass resource, the high-efficiency energy/resource utilization and proper disposal of straw possess has great significance in achieving the “dual carbon” goals. Straw is rich in organic matters, which can be used as raw material for producing high-value bio-based products through bioconversion processes. However, the complex and recalcitrant lignocellulosic structure limits its bioconversion efficiency. Therefore, appropriate pretreatment is a crucial step for high-efficiency bioconversion of straw. Based on the above analysis, this review systematically summarizes the advantages, limitations, and technological breakthroughs of the developed straw pretreatment technologies, and discusses the potential engineering applicability, economic feasibility and environmental sustainability of the integrated approach for directional enzymatic hydrolysis and bioconversion of straw, which is based on the in situ preparation of microbial consortium-based compound enzyme. Leveraging the multiple advantages of the microbial consortium-based compound enzyme, the proposed integrated approach can effectively reduce the pretreatment cost and enhance the bioconversion efficiency of straw. Although there are still some technical challenges in practical application, with the continuous advancement of relevant biological technologies, the proposed approach has the potential for large-scale industrial application.

Key words: straw, pretreatment, bioconversion, compound enzyme, full resources recovery