Carbon Sequestration by Microalgae and Engineering of Microalgal Cells by CRISPR Technology for Efficient CO₂ Capture for Carbon Neutral Bioproducts

Excess CO2 emissions cause global warming, a catastrophic effect that leads to ocean acidification, agricultural losses, droughts, disrupted rainfall, and emerging diseases. This ultimately impacts biodiversity, human health, and environmental sustainability. Hence, it is essential to reduce CO2 emissions to keep the planet cooler. Several countries set a carbon-neutral target of 50% by 2030 and net zero by 2070. To achieve carbon neutrality, several research communities and policymakers have developed innovative and economic solutions for carbon capture and sequestration. Biological carbon sequestration offers a more eco-friendly and sustainable approach to carbon capture than conventional methods. Microalgae act as potent biocatalysts, capturing CO2 through photosynthesis and producing biomass. The produced biomass serves as a resource for producing carbon-neutral bioproducts. This Review focuses on advances in microalgae-mediated carbon capture, sequestration, various microalgae cultivation strategies, and underlying mechanisms. At the end of the paper, various CRISPR-Cas-based gene-editing strategies aimed at enhancing photosynthesis are discussed, with a focus on key enzymes involved in efficient carbon capture and sequestration. Additionally, we highlight how the biomass generated through carbon fixation can be utilized for diverse bioproducts and conclude by addressing the future research priorities needed to optimize microalgae-based carbon sequestration for economically and environmentally sustainable bioprocesses.