Advances in capturing carbon and producing bioplastics through the microalgal approach towards a sustainable future: A review

The escalating levels of atmospheric carbon dioxide (CO 2 ) emissions caused by industrial activities have raised serious concerns, spurring the development of innovative carbon capture and utilization techniques. This study explores the use of microalgae for carbon capture from industrial flue gases, and converting it into bioplastics, specifically biodegradable polyhydroxyalkanoates (PHAs). Microalgae, recognized for their rapid growth and CO 2 sequestration capabilities, are cultivated using flue gas as a carbon source in photobioreactors or open ponds. Through photosynthesis, microalgae convert CO 2 into biomass rich in lipids, carbohydrates, and proteins, enabling both greenhouse gas mitigation and sustainable bioplastic production. The resulting PHAs exhibit properties similar to conventional plastics but are biodegradable, offering a promising alternative to petroleum-based plastics. These microalgae-based bioplastics have diverse applications in biomedical fields and industries, including packaging, disposable products, textiles, medical devices, 3D printing, agriculture, tissue engineering, and consumer goods. The integration of carbon capture technology using microalgae with sustainable bioplastic production forms a closed-loop system that addresses environmental challenges while contributing to a more sustainable and circular economy. This holistic strategy addresses pressing global challenges such as climate change, global warming, and plastic pollution, paving the way for a greener, less polluted future. • Algal biorefinery method is economically viable and cost-effective. • Using flue gases for microalgal growth enables unique bioplastics synthesis. • CO₂ utilization in microalgae biosynthetic pathways produces unique PHAs. • Circular economy benefits from flue gas use and plastic waste reduction. • Cleaner production practices improve resource efficiency in biorefineries.