Bioconversion of agricultural waste into bacterial single-cell protein: recent advances and modelling approaches

Abstract

Climate change and population growth are intensifying global pressure on food systems, demanding sustainable protein alternatives. While plant-based proteins represent important sustainable alternatives, rising global protein demand, environmental pressures, and limitations in agricultural expansion highlights the need for complementary protein sources such as microbial single-cell protein (SCP). This review examines the potential of bacterial SCP production from agricultural waste as a strategy to enhance food security and reduce environmental impact. This approach also aligns with the principle of circular economy by transforming waste materials into a valuable nutritional resource. Bacteria offer rapid growth, minimal land and water requirements, and broad substrate utilization, enabling efficient valorization of wastes. Key challenges arise from the recalcitrant structure of lignocellulosic residues, which necessitates effective pretreatment using physical, chemical, biological, or combined methods. The combined pretreatment approaches have been proven most effective in enhancing substrate accessibility. This review critically examines the mechanisms and pathways of bacterial SCP production from lignocellulosic wastes, with emphasis on process modelling, computational optimization, and emerging applications of artificial intelligence. Lastly, recent advances, current challenges, and future research directions are discussed. This review concludes that bacterial SCP represents a viable, climate-resilient solution for sustainable food systems, contributing to circular economy principles and global resource sustainability.

Keywords

Agrowaste / Valorization / Microbial protein / Mathematical modelling / Machine learning / Artificial intelligence

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Funding

Department of Biotechnology, Ministry of Science and Technology, India(DBTHRDPMU/JRF/BET-22/I/2022-23/140)

RIGHTS & PERMISSIONS

Jiangnan University