Biofuel production from lignocellulose via thermophile-based consolidated bioprocessing

Abstract

The depletion of fossil fuels and their impact on the environment have led to efforts to develop alternative sustainable fuels. While biofuel derived from lignocellulose is considered a sustainable, renewable, and green energy source, enhancing biofuel production and achieving a cost-effective bioconversion of lignocellulose at existing bio-refineries remains a challenge. Consolidated bioprocessing (CBP) using thermophiles can simplify this operation by integrating multiple processes, such as hydrolytic enzyme production, lignocellulose degradation, biofuel fermentation, and product distillation. This paper reviews recent developments in the conversion of lignocellulose to biofuel using thermophile-based CBP. First, advances in thermostable enzyme and thermophilic lignocellulolytic microorganism discovery and development for lignocellulosic biorefinery use are outlined. Then, several thermophilic CBP candidates and thermophilic microbes engineered to drive CBP of lignocellulose are reviewed. CRISPR/Cas-based genome editing tools developed for thermophiles are also highlighted. The potential applications of the Design-Build-Test-Learn (DBTL) synthetic biology strategy for designing and constructing thermophilic CBP hosts are also discussed in detail. Overall, this review illustrates how to develop highly sophisticated thermophilic CBP hosts for use in lignocellulosic biorefinery applications.

Keywords

Lignocellulose / Biofuel / Consolidated bioprocessing / Thermophile / Thermophilic enzymes

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

CRediT authorship contribution statement

Yilin Le: Writing - review & editing, Writing - original draft, Funding acquisition, Formal analysis, Data curation, Conceptualization. Mengqi Zhang: Investigation, Formal analysis, Data curation. Pengju Wu: Investigation, Formal analysis, Data curation. Huilei Wang: Writing - review & editing, Resources, Investigation, Funding acquisition, Formal analysis. Jinfeng Ni: Writing - review & editing, Project administration, Investigation, Formal analysis, Data curation, Conceptualization.

Acknowledgments

This work was supported by the Natural Science Foundation of Jiangsu Province, China (Grant NO. BK20231326); National Key R&D Program of China (2020YFA0906800); State Key Laboratory of Microbial Technology Open Projects Fund (Project NO. M2022-10).

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