Bansal Megha, Santhiya Deenan, Sharma Jai Gopal
Department of Biotechnology, Delhi Technological University, Delhi, India.
Department of Applied Chemistry, Delhi Technological University, Delhi, India.
J Hazard Mater. 2025 Aug 15;494:138545. doi: 10.1016/j.jhazmat.2025.138545. Epub 2025 May 9.
Bacterial culture isolates were used to demonstrate the breakdown of polypropylene (PPs) and polyvinyl chloride (PVCs) microplastics for the first time. Using metagenomics and phylogenetic analysis, bacterial isolates were discovered from a simulated dump yard. PPs and PVCs were broken down using bacterial isolates found to be Acinetobacter baumannii and mixed culture species with a Bacillus sp. dominance. After 50 days of activity, the dry weight of microplastics decreased by 33.3 % (PPs) and 27.1 % (PVCs) due to the breakdown process aided by Acinetobacter baumannii. Weight reductions of 20.3 % for PPs and 18.2 % for PVCs have been observed in mixed bacterial cultures, respectively. Microplastics' thermal stability and transition properties changed, according to experiments like DTG NMR, Raman, and WCA. FTIR analysis captured the structural changes in PPs and PVCs. SEM, TEM, and cell hydrophobicity tests showed that microplastics were biodegrading. GC-MS identified the released byproducts, which included carboxylic acids, alkanes, esters, and aromatic chemicals. Based on these findings, it can be concluded that bacterial isolates are effective in degrading PPs and PVCs and may help create sustainable methods of handling plastic trash.
细菌培养分离物首次被用于证明聚丙烯（PPs）和聚氯乙烯（PVCs）微塑料的分解。通过宏基因组学和系统发育分析，从一个模拟垃圾场中发现了细菌分离物。利用被发现为鲍曼不动杆菌的细菌分离物和以芽孢杆菌属为主的混合培养菌种对PPs和PVCs进行了分解。经过50天的活性作用，由于鲍曼不动杆菌辅助的分解过程，微塑料的干重分别下降了33.3%（PPs）和27.1%（PVCs）。在混合细菌培养物中，分别观察到PPs的重量减少了20.3%，PVCs的重量减少了18.2%。根据差示热重核磁共振（DTG NMR）、拉曼光谱和水接触角（WCA）等实验，微塑料的热稳定性和转变特性发生了变化。傅里叶变换红外光谱（FTIR）分析捕捉到了PPs和PVCs的结构变化。扫描电子显微镜（SEM）、透射电子显微镜（TEM）和细胞疏水性测试表明微塑料正在发生生物降解。气相色谱-质谱联用（GC-MS）鉴定出了释放的副产物，包括羧酸、烷烃、酯类和芳香族化合物。基于这些发现，可以得出结论，细菌分离物在降解PPs和PVCs方面是有效的，可能有助于创造处理塑料垃圾的可持续方法。
