title: Composition and variability of biofouling organisms in seawater reverse osmosis desalination plants.
abstract: Seawater reverse osmosis (SWRO) membrane biofouling remains a common challenge in the desalination industry, but the marine bacterial community that causes membrane fouling is poorly understood. Microbial communities at different stages of treatment processes (intake, cartridge filtration, and SWRO) of a desalination pilot plant were examined by both culture-based and culture-independent approaches. Bacterial isolates were identified to match the genera Shewanella, Alteromonas, Vibrio, and Cellulophaga based on 16S rRNA gene sequencing analysis. The 16S rRNA gene clone library of the SWRO membrane biofilm showed that a filamentous bacterium, Leucothrix mucor, which belongs to the gammaproteobacteria, accounted for nearly 30% of the clone library, while the rest of the microorganisms (61.2% of the total clones) were related to the alphaproteobacteria. 16S rRNA gene terminal restriction fragment length polymorphism (T-RFLP) analysis indicated that bacteria colonizing the SWRO membrane represented a subportion of microbes in the source seawater; however, they were quite different from those colonizing the cartridge filter. The examination of five SWRO membranes from desalination plants located in different parts of the world showed that although the bacterial communities from the membranes were not identical to each other, some dominant bacteria were commonly observed. In contrast, bacterial communities in source seawater were significantly different based on location and season. Microbial profiles from 14 cartridge filters collected from different plants also revealed spatial trends.
authors.affiliation: Civil and Environmental Engineering, University of California, Irvine, CA 92697, USA.
authors.forename: Minglu
authors.initials: M
authors.lastname: Zhang
authors.forename: Sunny
authors.initials: S
authors.lastname: Jiang
authors.forename: Dian
authors.initials: D
authors.lastname: Tanuwidjaja
authors.forename: Nikolay
authors.initials: N
authors.lastname: Voutchkov
authors.forename: Eric M V
authors.initials: EM
authors.lastname: Hoek
authors.forename: Baoli
authors.initials: B
authors.lastname: Cai
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D057219:Biofouling; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D008851:Micropore Filters / Q000382:microbiology*; D008969:Molecular Sequence Data; D058889:Molecular Typing; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D014462:Ultrafiltration / Q000379:methods; D018508:Water Purification
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S