Zhu Xiaomin, Duan Youren, Lu Jianqi, Xia Wei, Peng Yujia, Liu Jiawei, Dong Weiliang, Jiang Min
Key Laboratory for Waste Plastics Biocatalytic Degradation and Recycling, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.
State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
Front Microbiol. 2025 Aug 25;16:1638208. doi: 10.3389/fmicb.2025.1638208. eCollection 2025.
Polyurethane (PU), a segmented block copolymer with chemically resistant urethane linkages and tunable architecture, presents persistent biological recycling challenges. This study presents a Bacterial Laccase-Mediated System (BLMS) derived from for efficient degradation of polyester- and polyether-PU. Utilizing the laccase CotA and mediator 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), the BLMS demonstrated effective de polymerization of both commercial and self-synthesized PU foams, including polyester- and polyether-types. The weight loss of the self-synthesized polyester-foam and the commercial polyether-foam reached up to 21.24 ± 1.20% and 3.81 ± 0.36%, respectively. Subsequently, we detected oxygenated products such as ketones, alcohols, aldehydes, acids, esters, ethers, and 2,4- toluenediamine (2,4-TDA) indicating that bacterial laccase CotA exhibited redox catalytic activity toward PU. Moreover, an interesting phenomenon was observed during the degradation process that the solution turned purple. We predicted that this attribute to the enzymatic oxidation of ABTS to the radical cation ABTS, which subsequently reacts with 2,4-TDA to form the purple product. This study finds a plastic degrading enzyme capable of hydrolyzing urethane bonds in PU, offering a promising contribution to the development of a bio-based circular economy for PU biodegradation and recycling.
聚氨酯（PU）是一种具有耐化学性的聚氨酯键和可调节结构的嵌段共聚物，存在持续的生物循环利用挑战。本研究提出了一种源自[具体来源未提及]的细菌漆酶介导系统（BLMS），用于高效降解聚酯型和聚醚型PU。利用漆酶CotA和介质2,2'-联氮双（3-乙基苯并噻唑啉-6-磺酸）（ABTS），BLMS证明了对商业和自合成的PU泡沫（包括聚酯型和聚醚型）都有有效的解聚作用。自合成聚酯泡沫和商业聚醚泡沫的重量损失分别达到21.24±1.20%和3.81±0.36%。随后，我们检测到了含氧产物，如酮、醇、醛、酸、酯、醚和2,4-甲苯二胺（2,4-TDA），这表明细菌漆酶CotA对PU表现出氧化还原催化活性。此外，在降解过程中观察到一个有趣的现象，即溶液变成了紫色。我们预测这是由于ABTS被酶氧化成自由基阳离子ABTS，随后与2,4-TDA反应形成紫色产物。本研究发现了一种能够水解PU中聚氨酯键的塑料降解酶，为基于生物的PU生物降解和循环利用的循环经济发展做出了有前景的贡献。
