Zhang Le, Jiang Zicheng, Tsui To-Hung, Loh Kai-Chee, Dai Yanjun, Tong Yen Wah
NUS Environmental Research Institute, National University of Singapore, Singapore, Singapore.
Energy and Environmental Sustainability for Megacities (E2S2) Phase II, Campus for Research Excellence and Technological Enterprise (CREATE), Singapore, Singapore.
Front Bioeng Biotechnol. 2022 Jul 19;10:946085. doi: 10.3389/fbioe.2022.946085. eCollection 2022.
In the context of a circular economy, bioplastic production using biodegradable materials such as poly(3-hydroxybutyrate) (PHB) has been proposed as a promising solution to fundamentally solve the disposal issue of plastic waste. PHB production techniques through fermentation of PHB-accumulating microbes such as have been revolutionized over the past several years with the development of new strategies such as metabolic engineering. This review comprehensively summarizes the latest PHB production technologies fermentation. The mechanism of the biosynthesis pathway for PHB production was first assessed. PHB production efficiencies of common carbon sources, including food waste, lignocellulosic materials, glycerol, and carbon dioxide, were then summarized and critically analyzed. The key findings in enhancing strategies for PHB production in recent years, including pre-treatment methods, nutrient limitations, feeding optimization strategies, and metabolism engineering strategies, were summarized. Furthermore, technical challenges and future prospects of strategies for enhanced production efficiencies of PHB were also highlighted. Based on the overview of the current enhancing technologies, more pilot-scale and larger-scale tests are essential for future implementation of enhancing strategies in full-scale biogas plants. Critical analyses of various enhancing strategies would facilitate the establishment of more sustainable microbial fermentation systems for better waste management and greater efficiency of PHB production.
在循环经济背景下，使用聚（3-羟基丁酸酯）（PHB）等可生物降解材料生产生物塑料，被认为是从根本上解决塑料垃圾处理问题的一个有前景的解决方案。在过去几年里，通过代谢工程等新策略的发展，利用诸如能够积累PHB的微生物进行发酵的PHB生产技术发生了变革。本综述全面总结了最新的PHB生产技术——发酵技术。首先评估了PHB生物合成途径的机制。然后总结并批判性地分析了常见碳源（包括食物垃圾、木质纤维素材料、甘油和二氧化碳）的PHB生产效率。总结了近年来提高PHB生产的强化策略中的关键发现——包括预处理方法、营养限制、补料优化策略和代谢工程策略。此外，还强调了提高PHB生产效率策略的技术挑战和未来前景。基于对当前强化技术的概述，更多的中试规模和更大规模的测试对于未来在全规模沼气厂实施强化策略至关重要。对各种强化策略的批判性分析将有助于建立更可持续的微生物发酵系统以实现更好的废物管理和更高效率的PHB生产。
