Challenges, progress, and future perspectives for cyanobacterial polyhydroxyalkanoate production
Estel Rueda, Eva Gonzalez-Flo, Soumila Mondal, Karl Forchhammer, Dulce M. Arias, Katharina Ludwig, Bernhard Drosg, Ines Fritz, C. Raul Gonzalez‐Esquer, Sara Pacheco, Joan Garcı́a
Abstract
Abstract Polyhydroxyalkanoates (PHA) are a promising bio-based alternative to traditional plastics derived from petroleum. Cyanobacteria are photosynthetic organisms that produce PHA from CO 2 and sunlight, which can potentially reduce production costs and environmental footprint in comparison to heterotrophic bacteria cultures because (1) they utilize inorganic carbon sources for growth and (2) they do not require intensive aeration for oxygenation. Moreover, supplementing precursors such as propionate, acetate, valerate, etc., can be used to obtain various copolymers with plastic customizable properties in comparison to the classical homopolymers, such as polyhydroxybutyrate, PHB. This critical review covers the latest advances in PHA production, including recent discoveries in the metabolism interplay between PHA and glycogen production, and new insights into cultivation strategies that enhance PHA accumulation, and purification processes. This review also addresses the challenges and suggests potential solutions for a viable industrial PHAs production process.