Microbial cell factories for bio-based biodegradable plastics production.

The misuse of petroleum-based plastics has resulted in serious environmental pollution and resource wastage. Biodegradable plastics can be used as green substitutes for traditional plastics. Here, we discuss the feasibility and technical bottlenecks in developing microbial cell factories for the production of biodegradable plastics from lignocellulosic wastes. First, we introduce the basic properties of the main biodegradable plastics on the market, including poly(lactic acid), poly(hydroxyalkanoate), and poly(butylene adipate-co-terephthalate). We then demonstrate the feasibility of synthesizing petroleum-based biodegradable plastic monomers from bio-based raw materials and propose strategies to further advance their commercial production through metabolic engineering and synthetic biology. We also analyze the main challenges facing the current development of bio-based biodegradable plastic biosynthesis technology. Finally, we discuss the current major lignocellulose bioconversion processes and explore way to further improve the utilization efficiency of the main carbohydrates in lignocellulosic hydrolysates by microorganisms, from the perspectives of sugar transport, sugar assimilation, and carbon catabolite inhibition.