Microalgae as a Sustainable Bioresource for Bioplastic Production

ABSTRACT: Bioplastics are biomaterial-derived plastics and are superior to petrochemical-based plastics in terms of resource renewability, planetary sustainability, and environmental biodegradability. Extensive research has been carried out over the last decades to identify and characterize desirable biomaterials for bioplastic manufacturing, and among those explored, microalgal biomass has received special attention due to its numerous advantages over other bioresources, including high areal productivity, the potential to use non-arable land, and the ability to reduce waste. Nonetheless, the cultivation and biorefinery processes for microalgae still need innovative development to make microalgal bioplastics economically viable. The primary focus of this review is to examine the established and emerging technologies for manufacturing bioplastics from microalgal biomass, starting from the exploration of bioresource availability and outlining technical routes of production. In particular, both upstream and downstream processes of microalgal cultivation pertinent to bioplastic production are reviewed in detail, analyzed in depth, and evaluated from the perspective of economic viability. The technical challenges and research opportunities, as well as prospects of current approaches and future methodologies for microalgal production of bioplastics, are also discussed, mostly based upon our research experiences in microalgal bioengineering, and it is our opinion that, despite these existing challenges, microalgal biomass could still be one of the most promising feedstocks for sustainable manufacturing of bioplastics.