Polystyrene (PS), which accounts for a significant fraction of plastic wastes, is difficult to biodegrade due to its unique molecular structure. Therefore, biodegradation and chemical modification of PS are limited. In this study, we report PS biodegradation by the larvae of the darkling beetle Plesiophthalmus davidis (Coleoptera: Tenebrionidae). In 14 days, P. davidis ingested 34.27 ± 4.04 mg of Styrofoam (PS foam) per larva and survived by feeding only on Styrofoam. Fourier transform infrared spectroscopy confirmed that the ingested Styrofoam was oxidized. Gel permeation chromatography analysis indicated the decrease in average molecular weight of the residual PS in the frass compared with the feed Styrofoam. When the extracted gut flora was cultured for 20 days with PS films, biofilm and cavities were observed by scanning electron microscopy and atomic force microscopy. X-ray photoelectron spectroscopy (XPS) studies revealed that C-O bonding was introduced into the biodegraded PS film. Serratia sp. strain WSW (KCTC 82146), which was isolated from the gut flora, also formed a biofilm and cavities on the PS film in 20 days, but its degradation was less prominent than the gut flora. XPS confirmed that C-O and C=O bonds were introduced into the biodegraded PS film by Serratia sp. WSW. Microbial community analysis revealed that Serratia was in the gut flora in significant amounts and increased sixfold when the larvae were fed Styrofoam for 2 weeks. This suggests that P. davidis larvae and its gut bacteria could be used to chemically modify and rapidly degrade PS.

中文翻译：

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巨眼幼虫肠道微生物菌群对聚苯乙烯的快速、简便的生物降解。


聚苯乙烯（PS）占塑料废物的很大一部分，由于其独特的分子结构而难以生物降解。因此，PS的生物降解和化学改性受到限制。在这项研究中，我们报告了暗甲虫Plesiophamus davidis （鞘翅目：步甲科）幼虫对 PS 的生物降解作用。在 14 天的时间里， P. davidis每只幼虫摄入了 34.27 ± 4.04 毫克聚苯乙烯泡沫塑料（PS 泡沫），并且仅以聚苯乙烯泡沫塑料为食而存活。傅里叶变换红外光谱证实摄入的聚苯乙烯泡沫塑料被氧化。凝胶渗透色谱分析表明，与进料聚苯乙烯泡沫塑料相比，渣中残留PS的平均分子量降低。当提取的肠道菌群与PS膜一起培养20天时，通过扫描电子显微镜和原子力显微镜观察生物膜和空洞。 X 射线光电子能谱 (XPS) 研究表明，生物降解的 PS 薄膜中引入了 CO 键合。沙雷氏菌属从肠道菌群中分离出来的菌株WSW (KCTC 82146)也在20天内在PS膜上形成了生物膜和空洞，但其降解不如肠道菌群那么明显。 XPS 证实 CO 和 C=O 键被沙雷氏菌引入到生物降解的 PS 膜中。西西南。微生物群落分析显示，肠道菌群中沙雷氏菌的含量很高，当幼虫喂食聚苯乙烯泡沫塑料两周后，沙雷氏菌数量增加了六倍。这表明P. davidis幼虫及其肠道细菌可用于化学修饰和快速降解 PS。