title: Characterization of bacterial isolates from water reclamation systems on the basis of substrate utilization patterns and regrowth potential in reclaimed water.
abstract: Microbial regrowth causes problems during water reuse. Comprehensive understanding of the microorganisms that can regrow in reclaimed water and their substrate requirements are necessary. In this study, potential regrowth organisms were isolated from seven water reclamation plants in Japan. Based on 16S rDNA analysis, the isolates were grouped into 34 operational taxonomic units, belonging to Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes. Substrate utilization profiling using Biolog microplate™ classified the isolates into four groups. Bacteria in Cluster 1 (e.g., Methylobacterium sp. and Acinetobacter sp.) mainly utilized polymers, esters, amides, and alcohol. Isolates in Cluster 2 (e.g., Flavobacterium sp. and Microbacterium sp.) preferred to utilize polymers, carbohydrates, and esters. Isolates in Cluster 3 (e.g., Pseudomonas sp. and Acidovorax sp.) mainly utilized esters, carboxylic acids, and amino acids. Isolates in Cluster 4 (e.g., Enterobacter sp. and Rhodococcus sp.) utilized carbohydrates, esters, and amino acids. All isolates grew in reclaimed water treated by sand filtration, whereas some isolates could not grow in reclaimed water treated by coagulation and ozonation. Most bacteria in the same Biolog clusters exhibited similar growth characteristics in water samples. The potential of bacteria to regrow in reclaimed water likely depended on substrate requirement.
authors.affiliation: Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo Street, Bunkyo City, Tokyo, 113-8656, Japan E-mail: P.thayanukul@gmail.com.
authors.forename: Parinda
authors.initials: P
authors.lastname: Thayanukul
authors.forename: Futoshi
authors.initials: F
authors.lastname: Kurisu
authors.forename: Ikuro
authors.initials: I
authors.lastname: Kasuga
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Furumai
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000378:metabolism; D003247:Conservation of Natural Resources; D010802:Phylogeny; D059027:Recycling; D013997:Time Factors; D014865:Waste Disposal, Fluid; D014867:Water / Q000737:chemistry*; D014871:Water Microbiology; D018508:Water Purification
chemical_list: D014867:Water