Biotechnology and Phycology Division, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, 364002, India.
Academy of Scientific and Innovative Research (AcSIR), Council of Scientific and Industrial Research, New Delhi, India.
Environ Sci Pollut Res Int. 2019 Jan;26(2):1507-1516. doi: 10.1007/s11356-018-3465-1. Epub 2018 Nov 14.
Plastics are recalcitrant and inert to degrade, and destabilization leads to accumulate in the terrestrial and marine ecosystems; need for the development of strategies for reducing these plastic wastes in a sustainable manner would be revolutionary. We studied the bacterial adherence, degradation and destabilization of polyvinylchloride (PVC), low-density polyethylene (LDPE), and high-density polyethylene (HDPE) by marine bacterial strain AIIW2 by a series of analytical and microscopic observations over 3 months. Based on 16S rRNA gene sequence and the phylogenetic analysis of the strain AIIW2, it showed 97.39% similarity with Bacillus species. Degradation of plastics was determined by the weight loss after 90 days with bacterial strain which detected up to 0.26 ± 0.02, 0.96 ± 0.02, and 1.0 ± 0.01% for PVC, LDPE, and HDPE films, respectively over initial weights. The mineralization of plastic film was found to be maximum in LDPE followed by HDPE and PVC. Bacterial interaction had increased roughness and deteriorated the surface of plastics which is revealed by the scanning electron microscope and atomic force microscope. Bending vibrations of the alkane rock chain (-CH and -CH) and carbonyl (-CO) regions in LDPE and HDPE films, while there was slight stretching in the hydroxyl (-OH) regions of carboxylic acid in PVC which is evidenced through Fourier transform infrared spectral studies, suggested the oxidative activities of the bacteria. Though, the bacterial activity was higher on the LDPE and HDPE than PVC film which may be due to the presence of chlorine atom in PVC structure making it more versatile. The results of the present study revealed the ability of marine bacterial strain for instigating their colonization over plastic films and deteriorating the polymeric structure.
塑料具有很强的稳定性和惰性，难以降解，会在陆地和海洋生态系统中积累；因此需要开发可持续的策略来减少这些塑料废物，这将是革命性的。我们通过一系列分析和微观观察，研究了海洋细菌菌株 AIIW2 对聚氯乙烯（PVC）、低密度聚乙烯（LDPE）和高密度聚乙烯（HDPE）的细菌附着、降解和失稳作用，历时 3 个月。根据 16S rRNA 基因序列和菌株 AIIW2 的系统发育分析，其与芽孢杆菌属的相似度为 97.39%。通过 90 天后细菌菌株的重量损失来确定塑料的降解情况，检测到 PVC、LDPE 和 HDPE 薄膜的重量分别减少了 0.26±0.02%、0.96±0.02%和 1.0±0.01%。发现 LDPE 的塑料薄膜矿化程度最高，其次是 HDPE 和 PVC。扫描电子显微镜和原子力显微镜显示，细菌的相互作用增加了塑料的粗糙度并使其表面恶化。LDPE 和 HDPE 薄膜中烷烃岩链（-CH 和 -CH）和羰基（-CO）区域的弯曲振动，而 PVC 中羧酸的羟基（-OH）区域略有拉伸，这通过傅里叶变换红外光谱研究得到证实，表明了细菌的氧化活性。虽然，与 PVC 薄膜相比，LDPE 和 HDPE 薄膜上的细菌活性更高，这可能是由于 PVC 结构中存在氯原子，使其更具多功能性。本研究结果揭示了海洋细菌菌株在塑料薄膜上定殖和破坏聚合物结构的能力。
