小分子物质双(3-氨基丙基)胺对废水混合菌落生物膜形成抑制效应

研究了小分子物质双(3-氨基丙基)胺对混合菌落生物膜形成抑制及解体效应机制,并探讨了利用双(3-氨基丙基)胺减缓膜表面生物污染的可行性.结果表明,双(3-氨基丙基)胺能有效抑制混合菌群微生物附着和生物膜形成,抑制作用随浓度的升高而增强.经过双(3-氨基丙基)胺处理(131 mg·L~(-1))24 h,生物膜形成抑制率达到74.61%.这种抑制效果不是通过杀菌方式产生而是通过抑制微生物中胞外多糖和e DNA含量产生.经双(3-氨基丙基)胺处理后,胞外多糖和eDNA分别下降了39.37%±2.68%和70.05%±2.93%.双(3-氨基丙基)胺对已经形成的生物膜也有一定解离作用.对于预培养12 h的生物膜,双(3-氨基丙基)胺(131 mg·L~(-1))处理10 h,解体率为23.59%.另外双(3-氨基丙基)胺可减缓膜过滤过程中膜孔堵塞速度,降低膜压,缓解由微生物引起的膜污染问题,在环境膜污染控制方面具有潜在应用价值.

A small-molecule norspermidine inhibits biofilm formation for the mixed culture in wastewater

This study investigated the effects of norspermidine on the formation and disassembly of biofilm of mixed culture and its mechanism, and also explored the feasibility to control membrane fouling using norspermidine. The results show that norspermidine could effectively inhibit the microbial attachment and biofilm formation, and the inhibition efficiency increased with the increase of norspermidine concentration. After treatment with norspermidine (131 mg·L^-1) for 24 h, biofilm inhibition rate attained 74.61%. Norspermidine could retard bacterial adhesion and destruct biofilm matrix by reducing exopolysaccharides and extracellular DNA (eDNA) associated with bacteria instead of growth inhibition. Exopolysaccharides and eDNA associated with the suspended microorganisms were significantly reduced by 39.37%±2.68% and 70.05%±2.93% after treatment with norspermidine (131 mg·L^-1). Norspermidine could promote the disassembly of pre-formed biofilm. After 10 h contacting with 131 mg·L^-1 norspermidine, biofilm disassembly rate attained 23.59%. Furthermore, norspermidine can be used to retard membrane pore blocking during membrane filtration, reduce transmembrane pressure and membrane fouling resulted from microorganisms. Therefore, norspermidine also shows the potential application in environmental membrane fouling control.