Ben Abdallah Manel, Saadaoui Imen, Al-Ghouti Mohammad A, Zouari Nabil, Hahladakis John N, Chamkha Mohamed, Sayadi Sami
Biotechnology Program, Center for Sustainable Development, College of Arts and Sciences, Qatar University, Doha 2713, Qatar; Laboratory of Environmental Bioprocesses, Centre of Biotechnology of Sfax, BP 1177, 3018 Sfax, Tunisia.
Biotechnology Program, Center for Sustainable Development, College of Arts and Sciences, Qatar University, Doha 2713, Qatar.
Sci Total Environ. 2025 Feb 1;963:178452. doi: 10.1016/j.scitotenv.2025.178452. Epub 2025 Jan 17.
Polyhydroxyalkanoates (PHAs) are biodegradable and biocompatible polymers that can replace conventional plastics in different sectors. However, PHA commercialization is hampered due to their high production cost resulting from the use of high purity substrates, their low conversion into PHAs by using conventional microbial chassis and the high downstream processing cost. Taking these challenges into account, researchers are focusing on the use of waste by-products as alternative low-cost feedstocks for fast-growing and contamination-resistant halophilic microorganisms (Bacteria, Archaea…). This is of great importance since these extremophiles can use low-cost substrates, produce high PHA content of copolymers or different PHA monomer compositions. They can present high potential for reducing the costs of PHA fermentation and recovery processes, making their use in commercial applications easier. However, little is known about the potential of halophiles in advancing the PHA production from renewable waste materials at lab-scale and their successful implementation at industrial-scale. This review presents actual advances in PHA production by halophilic pure/engineered species (e.g. Haloferax mediterranei, Halomonas spp.) and mixed microbial consortia (MMC) using organic waste streams. The development of optimal PHA production process involves robust genetic engineering strategies, advanced fermentation processes using mixed microbial consortia versus pure/engineered strains as well as algal biomass as feedstocks.
聚羟基脂肪酸酯（PHA）是可生物降解且具有生物相容性的聚合物，可在不同领域替代传统塑料。然而，PHA的商业化受到阻碍，原因在于使用高纯度底物导致其生产成本高昂，使用传统微生物底盘时其转化为PHA的效率较低，以及下游加工成本较高。考虑到这些挑战，研究人员正专注于将废弃副产品用作快速生长且抗污染的嗜盐微生物（细菌、古菌等）的替代低成本原料。这非常重要，因为这些极端微生物可以利用低成本底物，生产高含量PHA的共聚物或不同的PHA单体组成。它们在降低PHA发酵和回收过程成本方面具有很大潜力，使其在商业应用中更易于使用。然而，关于嗜盐微生物在实验室规模从可再生废料推进PHA生产的潜力以及它们在工业规模的成功应用，人们了解甚少。本综述介绍了嗜盐纯培养/工程菌株（如地中海嗜盐古菌、嗜盐单胞菌属）和使用有机废物流的混合微生物群落（MMC）在PHA生产方面的实际进展。优化PHA生产工艺的发展涉及强大的基因工程策略、使用混合微生物群落而非纯/工程菌株以及以藻类生物质为原料的先进发酵工艺。
