Abstract:

Polyhydroxyalkanoates （PHAs） are a type of high molecular⁃weight bio⁃polyesters synthesized within microbial cells and have attracted widespread attention due to their potential to replace traditional petroleum⁃based raw materials for the preparation of biodegradable thermoplastics. However， the high cost of PHAs currently limits their large⁃scale production and applications. Developing a technology to synthesize PHAs using low⁃cost carbon sources is one of the most effective ways to reduce their costs. The anaerobic fermentation liquor obtained from organic waste is rich in volatile fatty acids and can serve as an excellent substrate for the synthesis of PHAs. Utilizing anaerobic fermentation liquor for the synthesis of PHAs not only can obtain the resourceful utilization of waste but also can produce PHAs to replace traditional petroleum⁃based thermoplastic materials. Meanwhile， the production cost of PHAs can be reduced. Taking the synthesis of PHAs derived from low⁃cost carbon sources as an important direction for reducing production costs， this paper mainly discussed the mechanism of organic waste anaerobic fermentation and focused on the research progress and influencing factors related to the synthesis of PHAs from the anaerobic fermentation liquor of sludge and kitchen waste. Finally， the paper gave an outlook on future research directions for synthesizing PHAs using anaerobic fermentation liquor as a substrate.

Key words: polyhydroxyalkanoate, degradable plastic, anaerobic fermentation, volatile fatty acid, low cost, microbial synthesis