供水PE和PPR塑料管内表面生物膜群落组成及其代谢特征

Biofilm bacterial community composition and metabolic characteristics on the inner surface of PE and PPR plastic pipes

饮用水管道材料可以影响管壁生物膜群落组成,其代谢功能的差异又会导致不同的微生物风险.以PE管和PPR管为实验对象,结合16S rRNA测序、非靶向代谢组学、流式细胞仪和激光共聚焦扫描显微镜等方法,探究不同塑料管材对管壁生物膜微生物群落组成、代谢过程和微生物量的影响.结果表明,PPR管生物膜中微生物多样性和丰富度明显高于PE管.PPR管生物膜中变形菌门和拟杆菌门相对丰度高于PE管,PE管生物膜中放线菌门和酸杆菌门相对丰度高于PPR管.PE管壁生物膜中微生物代谢产物主要为十五烷酸、棕榈油酸和乙底酚等物质,PPR管生物膜中微生物代谢产物主要有13-氧化ODE、间香豆酸、7-羟基香豆素和松三糖等物质.相比于PPR管,PE管生物膜中与微生物代谢产物相对应的代谢通路包括核苷酸代谢、脂肪酸的生物合成和嘌呤代谢等表达量显著上调.与PPR管相比,PE管生物膜厚度更厚、微生物量更多,活菌比例更高,容易导致更强的微生物风险.因此,建议以后深入探究不同材质的塑料管对生物膜形成的影响机制并提出相应控制措施,以确保饮用水塑料管网水质微生物安全.

Pipe materials can affect the biofilm bacterial community composition,and their different metabolic functions can lead to different microbial risks of drinking water.In this study,PE and PPR pipes were used as experimental subjects.The 16S rRNA sequencing,untargeted metabolomics,flow cytometry and confocal laser scanning microscopy(CLSM)were used to investigate the effects of different plastic pipes on the biofilm bacterial community composition,metabolic processes and the biomass on the inner surface of different pipes.The results showed that the microbial diversity and abundance of biofilm in PPR pipes was significantly higher than that of PE pipes.The microbial diversity and abundance of the bacterial communities in biofilm of PPR pipes was significantly higher than that of the PE pipes.The relative abundance of Proteobacteria and Bacteroidetes in biofilm of PPR pipes was higher than that of the PE pipes,and the relative abundance of Actinobacteria and Acidobacteria in biofilm of PE pipes was higher than that of the PPR pipes.The main microbial metabolites of biofilm in PE pipes were pentadecanoic acid,palmitoleic acid and diethylstilbestrol,while those of PPR pipes were 13-oxo-ODE,m-Coumaric acid,umbelliferone,and melezitose.Compared to PPR pipes,the main microbial metabolic pathways in biofilm of PE pipes,including nucleotide metabolism,fatty acid biosynthesis and purine metabolism,were up-regulated significantly.The biofilm of PE pipes had higher thickness and more biomass than that of PPR pipes.The higher percentage of live bacteria was also higher in PE pipes biofilm,which leading to stronger microbial risk of drinking water.Therefore,it is recommended to further explore the influence mechanism of different plastic pipes on biofilm formation and put forward the corresponding control methods,in order to guarantee the microbial safety of drinking water.