摘要
【目的】针对聚对苯二甲酸乙二醇酯(polyethylene terephthalate, PET)塑料在环境中造成的污染问题,筛选具备PET降解能力的功能菌株,分析其生长特性与降解能力,为PET废弃物的生物修复提供理论依据和菌种资源支持。【方法】从垃圾填埋场周边土壤样品中分离筛选可降解PET的菌株,通过形态学观察、生理生化测试以及16S rRNA基因序列分析对菌株进行鉴定。采用扫描电子显微镜(scanning electron microscope, SEM)、傅里叶变换红外光谱(Fourier transform infrared spectroscopy, FTIR)和水接触角(water contact angle, WCA)测试分析PET薄膜降解前后的表面形貌与官能团变化,并通过高效液相色谱(high performance liquid chromatography, HPLC)检测降解产物的种类和含量。【结果】成功筛选获得一株PET降解菌YH-1,经16S rRNA基因分析鉴定为纤维微菌属(Cellulosimicrobium sp.) YH-1。该菌株的最适生长条件为温度35℃、pH 7.0、盐度1%,且在pH 6.0-10.0及盐度1%-4%范围内均表现出良好的生长能力。降解实验结果显示,菌株YH-1培养6 d后可实现1.90%的PET失重率。HPLC分析结果表明,降解产物中对苯二甲酸(terephthalic acid, TPA)和双(2-羟乙基)对苯二甲酸酯[bis(2-hydroxyethyl) terephthalate, BHET]含量分别为3.87 mg/L和4.70 mg/L。SEM观察显示,降解后的PET膜表面出现明显裂痕和粗糙结构;FTIR检测显示其官能团发生变化;WCA测试结果显示其水接触角由79.385°降至65.052°,表明薄膜亲水性显著增强。【结论】菌株YH-1具有良好的环境适应能力和一定的PET降解潜力,能够破坏PET膜表面结构并产生典型降解产物,为后续PET生物降解菌资源的开发和降解机制研究提供了理论基础和技术支持。
[Objective]To address the environmental pollution caused by polyethylene terephthalate(PET),we screened functional bacterial strains capable of degrading PET and analyzed their growth and degradation characteristics,aiming to provide theoretical support and microbial resources for PET bioremediation.[Methods]Bacterial strains capable of degrading PET were isolated from the soil samples collected around a landfill site.The selected strain was identified based on morphological characteristics,physiological and biochemical properties,and 16S rRNA gene sequencing.The surface morphology and chemical group changes of PET films before and after degradation were analyzed by scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR),and water contact angle(WCA)measurements.The types and concentrations of degradation products were quantified via high-performance liquid chromatography(HPLC).[Results]A PET-degrading strain,designated YH-1,was successfully isolated and identified as a member of the Cellulosimicrobium sp.genus based on 16S rRNA analysis.The optimal growth conditions for strain YH-1 were 35℃,pH 7.0,and 1%salinity,and the strain exhibited robust growth within the ranges of pH 6.0−10.0 and 1%−4%salinity.After 6 days of incubation,YH-1 achieved a PET weight loss rate of 1.90%.HPLC revealed that terephthalic acid(TPA)and bis(2-hydroxyethyl)terephthalate(BHET)were the main degradation products,with concentrations of 3.87 mg/L and 4.70 mg/L,respectively.SEM images showed obvious surface roughening and cracking of the PET film after degradation,while FTIR revealed changes in functional groups.WCA measurements showed a reduction in contact angle from 79.385°to 65.052°,indicating enhanced hydrophilicity of the degraded PET film surface.[Conclusion]Strain YH-1 demonstrates good environmental adaptability and PET degradation potential.It can disrupt the PET film surface and generate typical degradation products.The findings lay a foundation for further development of PET-degrading microbial resources and exploration of degradation mechanisms.
作者
俞静波
黄莉蓉
刘佳文
王宇梅
魏粤昊
何跃辉
张磊
YU Jingbo;HUANG Lirong;LIU Jiawen;WANG Yumei;WEI Yuehao;HE Yuehui;ZHANG Lei(School of Ocean Food and Biological Engineering,Jiangsu Ocean University,Lianyungang,Jiangsu,China)
出处
《微生物学报》
北大核心
2025年第12期5438-5451,共14页
Acta Microbiologica Sinica
基金
江苏省高等学校基础科学(自然科学)研究面上项目(23KJB180006)
江苏省海洋资源开发技术创新中心科技计划(LWJJ-10)
江苏省研究生科研与实践创新计划(SJCX24_2085)。
