Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela, 769 008, Odisha, India.
Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela, 769 008, Odisha, India.
Chemosphere. 2023 Sep;334:138928. doi: 10.1016/j.chemosphere.2023.138928. Epub 2023 May 19.
Increasing usage of plastic has led to the deposition of plastic in the environment which later become microplastic, a pollutant of global concern. These polymeric particles affect the ecosystem by increasing ecotoxicity and impeding the biogeochemical cycles. Besides, microplastic particles have been known for their role in aggravating the effect of various other environmental pollutants including organic pollutants and heavy metals. These microplastic surfaces are often colonized by the microbial communities also known as "plastisphere microbes" forming biofilms. These microbes include cyanobacteria like Nostoc, Scytonema, etc., and diatoms like Navicula, Cyclotella, etc. which become the primary colonizer. In addition to the autotrophic microbes, Gammaproteobacteria and Alphaproteobacteria dominate the plastisphere microbial community. These biofilm-forming microbes can efficiently degrade the microplastic in the environment by secreting various catabolic enzymes such as lipase, esterase, hydroxylase, etc. Besides, these microbes have shown great potential for the bioconversion of microplastic to polyhydroxyalkanoates (PHA), an energy efficient and sustainable alternative to the petroleum based plastics. Thus, these microbes can be used for the creation of a circular economy using waste to wealth strategy. This review provides a deeper insight into the distribution, transportation, transformation, and biodegradation of microplastic in the ecosystem. The formation of plastisphere by the biofilm-forming microbes has been described in the article. In addition, the microbial metabolic pathways and genetic regulations involved in the biodegradation have been discussed in detail. The article suggests the microbial bioremediation and upcycling of microplastic along with various other strategies to effectively mitigate the microplastic pollution.
塑料的使用量不断增加，导致塑料在环境中沉积，后来成为微塑料，这是一种全球关注的污染物。这些聚合物颗粒通过增加生态毒性和阻碍生物地球化学循环来影响生态系统。此外，微塑料颗粒已被证明在加剧各种其他环境污染物（包括有机污染物和重金属）的影响方面发挥作用。这些微塑料表面经常被微生物群落（也称为“塑料球微生物”）定殖，形成生物膜。这些微生物包括蓝藻如 Nostoc、Scytonema 等，以及硅藻如 Navicula、Cyclotella 等，它们成为主要的定植者。除了自养微生物外，γ-变形菌纲和α-变形菌纲在塑料球微生物群落中占主导地位。这些形成生物膜的微生物可以通过分泌各种代谢酶（如脂肪酶、酯酶、羟化酶等）有效地降解环境中的微塑料。此外，这些微生物在将微塑料生物转化为聚羟基烷酸（PHA）方面显示出巨大的潜力，PHA 是一种比石油基塑料更节能和可持续的替代品。因此，这些微生物可以用于创建一种利用废物创造财富的循环经济。这篇综述深入探讨了微塑料在生态系统中的分布、迁移、转化和生物降解。文章中描述了生物膜形成微生物形成塑料球的过程。此外，还详细讨论了参与生物降解的微生物代谢途径和遗传调控。文章提出了微生物生物修复和微塑料的升级利用以及各种其他策略，以有效减轻微塑料污染。
