Atal Centre for Ocean Science and Technology for Islands, National Institute of Ocean Technology, Ministry of Earth Sciences, Government of India, Port Blair 744103, Andaman and Nicobar Islands, India.
Atal Centre for Ocean Science and Technology for Islands, National Institute of Ocean Technology, Ministry of Earth Sciences, Government of India, Port Blair 744103, Andaman and Nicobar Islands, India.
J Hazard Mater. 2022 Mar 5;425:128005. doi: 10.1016/j.jhazmat.2021.128005. Epub 2021 Dec 7.
The omnipresent accumulation and non-degradable nature of plastics in the environment are posing an ever-increasing ecological threat. In this study, a total of 97 bacteria were isolated from macroplastic debris collected from the coastal environments of Andaman Island. The isolates were screened for LDPE degradation potential and were identified based on phenotypic, biochemical, and molecular characterization. 16S rDNA-based identification revealed that three-three isolates of each belong to the genus Oceanimonas and Vibrio, two were closely related to the genus Paenibacillus whereas, one-one was associated with the genus Shewanella, Rheinheimera, and Bacillus, respectively. A bacterial consortium was formulated using the top four isolates based on their individual LDPE degradation potentials. A significant increase (p < 0.05) in the mean LDPE degradation (47.07 ± 6.67% weight-loss) and change in thickness was observed after 120 days of incubation. FTIR spectrum, C NMR, and TG-DSC analyses demonstrated changes in the LDPE sheets' functional groups, crystallinity, and in thermal properties after 120 days of incubation. The SEM and AFM images confirmed bacterial attachments, an increase in surface roughness and deformities on LDPE sheets. This study reports a bacterial consortium that can efficiently degrade the plastics and can be used in providing eco-friendly mitigation of plastic waste.
在环境中,塑料无处不在且不可降解,这对生态造成了日益严重的威胁。本研究从安达曼群岛沿海环境中收集的大块塑料碎片中分离出了 97 株细菌。这些分离株经过筛选具有低密度聚乙烯(LDPE)的降解潜力,并通过表型、生化和分子特征进行鉴定。基于 16S rDNA 的鉴定结果表明,其中三株属于海洋单胞菌属和弧菌属,两株与类芽孢杆菌属密切相关,一株与希瓦氏菌属、莱茵海默氏菌属和芽孢杆菌属分别相关。根据各自的 LDPE 降解潜力,选择前 4 株分离株来构建细菌共生体。经过 120 天的培养,观察到显著的平均 LDPE 降解(47.07±6.67%重量损失)和厚度变化(p<0.05)。FTIR 光谱、C NMR 和 TG-DSC 分析表明,经过 120 天的培养后,LDPE 薄片的功能基团、结晶度和热性能发生了变化。SEM 和 AFM 图像证实了细菌的附着,LDPE 薄片表面的粗糙度和变形增加。本研究报告了一种能够有效降解塑料的细菌共生体,可用于提供环保的塑料废物缓解措施。