APESA, Pôle Valorisation, 64121 Montardon, France; Université de Pau et des Pays de l'Adour / E2S UPPA / CNRS, IPREM UMR5254, Institut des Sciences Analytiques et de Physicochimie pour l'Environnement et les Matériaux, Chimie et Microbiologie de l'Environnement, 64000, Pau, France.
APESA, Pôle Valorisation, 64121 Montardon, France.
J Hazard Mater. 2023 Feb 5;443(Pt A):130208. doi: 10.1016/j.jhazmat.2022.130208. Epub 2022 Oct 20.
Biodegradable plastics, if they are not properly managed at their end-of-life, can have the same hazardous environmental consequences as conventional plastics. This study investigates the treatment of the main biodegradable plastics under mesophilic and thermophilic anaerobic digestion using biochemical methane potential test and the microorganisms involved in the process using amplicon sequencing of the 16 S rRNA. Here we showed that, only PHB and TPS undergone important and rapid biodegradation under mesophilic condition (38 °C). By contrast, PCL and PLA exhibited very low biodegradation rate as 500 days were required to reach the ultimate methane yield. Little or no degradation occurred for PBAT and PBS at 38 °C. Under thermophilic conditions (58 °C), TPS, PHB, and PLA reached high levels of biodegradation in a relatively short period (< 100 d). While PBS, PBAT, and PCL could not be converted into methane at 58 °C. PHB degraders (Enterobacter and Cupriavidus) and lactate-utilizing bacteria (Moorella and Tepidimicrobium) appeared to play an important role in the PHB and PLA degradation, respectively. This work not only provides crucial data on the anaerobic digestion of the main biodegradable plastics but also enriches the understanding of the microorganisms involved in this process, which are of great importance for future development of the treatment of biodegradable plastics in anaerobic digestion systems.
可生物降解塑料，如果在其使用寿命结束时得不到妥善处理，可能会产生与传统塑料相同的有害环境后果。本研究使用生物化学甲烷潜力测试和 16S rRNA 扩增子测序调查了主要可生物降解塑料在中温和高温厌氧消化下的处理方法，以及参与该过程的微生物。在这里，我们表明，只有 PHB 和 TPS 在中温（38°C）条件下经历了重要且快速的生物降解。相比之下，PCL 和 PLA 的生物降解率非常低，需要 500 天才能达到最终的甲烷产量。PBAT 和 PBS 在 38°C 下几乎没有或没有降解。在高温（58°C）条件下，TPS、PHB 和 PLA 在相对较短的时间（<100 天）内达到了较高的生物降解水平。而 PBS、PBAT 和 PCL 不能在 58°C 下转化为甲烷。PHB 降解菌（肠杆菌属和贪铜菌属）和利用乳酸的细菌（莫拉氏菌属和嗜热微菌属）似乎分别在 PHB 和 PLA 的降解中发挥了重要作用。这项工作不仅提供了主要可生物降解塑料厌氧消化的关键数据，还丰富了对参与该过程的微生物的理解，这对于未来开发可生物降解塑料在厌氧消化系统中的处理方法具有重要意义。
