Choonut Aophat, Wongfaed Nantharat, Wongthong Lalita, Poolpol Auraiwan, Chaikitkaew Srisuda, Sittijunda Sureewan, Reungsang Alissara
Faculty of Environment and Resource Studies Mahidol University, Nakhon Pathom 73170, Thailand; Department of Biotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen 40002, Thailand.
Department of Biotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen 40002, Thailand; Research Group for Development of Microbial Hydrogen Production Process from Biomass, Khon Kaen University, Khon Kaen 40002, Thailand.
J Hazard Mater. 2025 Jun 15;490:137806. doi: 10.1016/j.jhazmat.2025.137806. Epub 2025 Mar 3.
The persistence of plastics, particularly polypropylene (PP), and their conversion into microplastics (MPs), specifically PP-MPs, have emerged as serious ecological threats to soil and aquatic environments. In the present study, we aimed to isolate a microbial consortium capable of degrading PP-MPs. The results revealed that three microbial consortia (CPP-KKU1, CPP-KKU2, and CPP-KKU3) exhibited the ability to degrade PP-MPs, achieving weight losses ranging from 11.6 ± 0.2 % to 17.8 ± 0.5 % after 30 days. Fourier transform infrared (FTIR) spectroscopy analysis confirmed the degradation through oxidation, as evidenced by the presence of new functional groups (-OH and -C=O). In particular, CPP-KKU3 showed the highest degradation efficiency, with scanning electron microscopy (SEM) analysis revealing surface cracking after treatment. Additionally, gas chromatography-mass spectrometry (GC-MS) analysis identified various intermediate compounds, including heterocyclic aromatic compounds, phenyl groups, methylthio derivatives, and ethoxycarbonyl derivatives, indicating complex biochemical processes that were likely mediated by microbial enzymes. Furthermore, polyhydroxybutyrate (PHB) production by these consortia was also investigated. The result showed that both CPP-KKU2 and CPP-KKU3 successfully produced PHB, with CPP-KKU3 demonstrating superior performance in terms of PP-MP degradation and PHB production. Metagenomic analysis of CPP-KKU3 revealed abundant carbohydrate-active enzymes (CAZymes), particularly glycosyl transferases and glycoside hydrolases, which are associated with MP digestion. This study presents a promising bioremediation approach that addresses plastic waste degradation and sustainable bioplastic production, offering a potential solution for environmental plastic pollution.
塑料，尤其是聚丙烯（PP）的持久性及其向微塑料（MPs）的转化，特别是PP-MPs，已成为对土壤和水环境的严重生态威胁。在本研究中，我们旨在分离出能够降解PP-MPs的微生物群落。结果表明，三个微生物群落（CPP-KKU1、CPP-KKU2和CPP-KKU3）表现出降解PP-MPs的能力，30天后重量损失范围为11.6±0.2%至17.8±0.5%。傅里叶变换红外（FTIR）光谱分析证实了通过氧化进行的降解，新官能团（-OH和-C=O）的存在证明了这一点。特别是，CPP-KKU3表现出最高的降解效率，扫描电子显微镜（SEM）分析显示处理后表面出现裂纹。此外，气相色谱-质谱（GC-MS）分析鉴定出各种中间化合物，包括杂环芳烃化合物、苯基、甲硫基衍生物和乙氧羰基衍生物，表明可能由微生物酶介导的复杂生化过程。此外，还研究了这些群落产生聚羟基丁酸酯（PHB）的情况。结果表明，CPP-KKU2和CPP-KKU3均成功产生了PHB，CPP-KKU3在PP-MP降解和PHB产生方面表现出卓越性能。对CPP-KKU3的宏基因组分析揭示了丰富的碳水化合物活性酶（CAZymes），特别是糖基转移酶和糖苷水解酶，它们与MP消化有关。本研究提出了一种有前景的生物修复方法，该方法解决了塑料废物降解和可持续生物塑料生产问题，为环境塑料污染提供了潜在解决方案。
