Costa Paolo, Basaglia Marina, Casella Sergio, Favaro Lorenzo
Waste-to-Bioproducts Lab, Department of Agronomy, Food, Natural resources, Animals and Environment (DAFNAE), University of Padova, Agripolis, Viale dell'Università, 16, 35020 Legnaro, PD, Italy.
Waste-to-Bioproducts Lab, Department of Agronomy, Food, Natural resources, Animals and Environment (DAFNAE), University of Padova, Agripolis, Viale dell'Università, 16, 35020 Legnaro, PD, Italy; Department of Microbiology, Stellenbosch University, Private Bag X1, 7602 Matieland, South Africa.
Int J Biol Macromol. 2024 Aug;275(Pt 2):133575. doi: 10.1016/j.ijbiomac.2024.133575. Epub 2024 Jul 2.
Traditional plastics reshaped the society thanks to their brilliant properties and cut-price manufacturing costs. However, their protracted durability and limited recycling threaten the environment. Worthy alternatives seem to be polyhydroxyalkanoates, compostable biopolymers produced by several microbes. The most common 3-hydroxybutyrate homopolymer has limited applications calling for copolymers biosynthesis to enhance material properties. As a growing number of researches assess the discovery of novel comonomers, great endeavors are dedicated as well to copolymers production scale-up, where the choice of the microbial carbon source significantly affects the overall economic feasibility. Diving into novel metabolic pathways, engineered strains, and cutting-edge bioprocess strategies, this review aims to survey up-to-date publications about copolymers production, focusing primarily on precursors origins. Specifically, in the core of the review, copolymers precursors have been divided into three categories based on their economic value: the costliest structurally related ones, the structurally unrelated ones, and finally various low-cost waste streams. The combination of cheap biomasses, efficient pretreatment strategies, and robust microorganisms paths the way towards the development of versatile and circular polymers. Conceived to researchers and industries interested in tackling polyhydroxyalkanoates production, this review explores an angle often underestimated yet of prime importance: if PHAs copolymers offer advanced properties and sustainable end-of-life, the feedstock choice for their upstream becomes a major factor in the development of plastic substitutes.
传统塑料凭借其卓越的性能和低廉的制造成本重塑了社会。然而，它们的持久耐用性和有限的可回收性对环境构成了威胁。值得关注的替代品似乎是聚羟基脂肪酸酯，这是由几种微生物产生的可堆肥生物聚合物。最常见的3-羟基丁酸均聚物应用有限，需要通过共聚物生物合成来增强材料性能。随着越来越多的研究评估新型共聚单体的发现，人们也在大力致力于扩大共聚物的生产规模，其中微生物碳源的选择会显著影响整体经济可行性。本综述深入探讨了新型代谢途径、工程菌株和前沿生物工艺策略，旨在调查有关共聚物生产的最新出版物，主要关注前体的来源。具体而言，在综述的核心部分，共聚物前体根据其经济价值分为三类：成本最高的结构相关前体、结构不相关的前体，以及各种低成本废物流。廉价生物质、高效预处理策略和强大的微生物的结合为通用和循环聚合物的开发铺平了道路。本综述是为对解决聚羟基脂肪酸酯生产感兴趣的研究人员和行业而撰写的，探讨了一个经常被低估但至关重要的角度：如果聚羟基脂肪酸酯共聚物具有先进的性能和可持续的生命周期结束方式，那么其上游原料的选择就成为塑料替代品开发的一个主要因素。
