title: Physiological Responses of Salinity-Stressed Vibrio sp. and the Effect on the Biofilm Formation on a Nanofiltration Membrane.
abstract: This study evaluated the effects of salinity on the physiological characteristics of Vibrio sp. B2 and biofilm formation on nanofiltration (NF) membrane coupons used in the high recovery seawater desalination process. The test conditions were at 0.6, 1.2, and 2.4 M sodium chloride (NaCl), equivalent to salinity of seawater, brine at 50% and 75% water recovery, respectively. High salinity inhibited the cell growth rate but increased the viability and bacterial membrane integrity. In addition, protein and eDNA concentrations of salinity-stressed bacteria were increased at 1.2 and 2.4 M NaCl. In particular, protein concentration was linearly correlated with the NaCl concentration. Similarly, less biofilm formation on the NF membrane coupon (without permeation flux) was observed by the salinity-stressed bacteria; however, the production of extracellular polymeric substances (EPS) was significantly increased as compared to control, and protein was an influential factor for biofilm formation. This study shows that salinity-stressed bacteria have a high potential to cause biofouling on membrane surface as the bacteria still maintain the cell activity and overproduce EPS. The potential of biofilm formation by the salinity-stressed bacteria has not been reported. Therefore, the findings are important to understand the mechanisms of membrane biofouling in a high salinity environment.
authors.affiliation: Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University , 1 Cleantech Loop, CleanTech One 06-08, Singapore 637141, Singapore.
authors.forename: Lan Hee
authors.initials: LH
authors.lastname: Kim
authors.affiliation: Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University , 1 Cleantech Loop, CleanTech One 06-08, Singapore 637141, Singapore.|School of Civil and Environmental Engineering, Nanyang Technological University , 50 Nanyang Avenue, Singapore 639798, Singapore.
authors.forename: Tzyy Haur
authors.identifier: 0000-0002-1387-7464
authors.initials: TH
authors.lastname: Chong
mesh_terms: D018441:Biofilms; D057219:Biofouling; D008567:Membranes, Artificial; D054712:Salinity; D014733:Vibrio
chemical_list: D008567:Membranes, Artificial