Biofilm metagenomic

This study investigated the physicochemical surface changes of various plastics caused by indigenous communities. The first invading microbes on plastics in 4 different aquatic communities including seawater, freshwater, marine sediments and lake sediments were developed in microcosm incubation experiments. A mixture of weathered plastics (PE, PS, PET) was incubated with different indigenous communities under their respective habitat simulations. All microbial communities were able to form populations on all plastic surfaces with time-dependent development. Biofilm also affected floatation of plastics and the communities on PE foam (PF) were dominated by genera affiliated with plastic and hydrocarbon degraders. The results showed that indigenous populations were able to degrade plastic pieces and utilize them as carbon sources where the weight of PF was reduced more effectively than PS and PET. Besides, carbonyl groups that were seen with FTIR on initial PF disappeared after microbial treatment along with signs of bioerosion on the plastic surface.

本研究围绕本土微生物群落（indigenous communities）诱导的多种塑料表面物理化学变化展开探究。针对海水、淡水、海洋沉积物及湖泊沉积物四类不同水生环境，本研究通过微宇宙培养实验获取了塑料表面的首批定殖微生物。将风化塑料混合物（聚乙烯(PE)、聚苯乙烯(PS)、聚对苯二甲酸乙二酯(PET)）与不同本土微生物群落，在各自对应的生境模拟条件下进行共培养。所有微生物群落均可随培养时间推移在所有塑料表面形成稳定种群，其定殖过程呈现时间依赖性。生物膜同样会对塑料的漂浮特性产生影响，而聚乙烯泡沫(PF)表面的微生物群落以隶属于塑料降解菌及烃类降解菌的菌属为优势类群。研究结果显示，本土微生物群落能够降解塑料碎片并将其作为碳源加以利用，其中聚乙烯泡沫的重量削减效率显著优于聚苯乙烯与聚对苯二甲酸乙二酯。此外，经傅里叶变换红外光谱(FTIR)检测到的初始聚乙烯泡沫表面的羰基基团，在微生物处理后完全消失，同时塑料表面出现了生物侵蚀的典型特征。