Usage of and diverse microalgae for CO capture - towards a bioenergy revolution.

To address climate change threats to ecosystems and the global economy, sustainable solutions for reducing atmospheric carbon dioxide (CO) levels are crucial. Existing CO capture projects face challenges like high costs and environmental risks. This review explores leveraging microalgae, specifically the genus, for CO capture and conversion into valuable bioenergy products like biohydrogen. The introduction section provides an overview of carbon pathways in microalgal cells and their role in CO capture for biomass production. It discusses current carbon credit industries and projects, highlighting the genus's carbon concentration mechanism (CCM) model for efficient CO sequestration. Factors influencing microalgal CO sequestration are examined, including pretreatment, pH, temperature, irradiation, nutrients, dissolved oxygen, and sources and concentrations of CO. The review explores microalgae as a feedstock for various bioenergy applications like biodiesel, biooil, bioethanol, biogas and biohydrogen production. Strategies for optimizing biohydrogen yield from are highlighted. Outlining the possibilities of further optimizations the review concludes by suggesting that microalgae and -based CO capture is promising and offers contributions to achieve global climate goals.