title: Isolation and characterization of a phenol-degrading bacterium from an industrial activated sludge.
abstract: This paper reports the successful isolation and characterization of a new phenol-degrading bacterium, strain EDP3, from activated sludge. Strain EDP3 is a nonmotile, strictly aerobic, Gram-negative, and short-rod or coccobacillary bacterium, which occurs singly, in pairs, or in clusters. 16S rRNA gene sequence analysis revealed that strain EDP3 belonged to the gamma group of Proteobacteria, with a 97.0% identity to 16S rRNA gene sequences of Acinetobacter calcoaceticus. Strain EDP3 could aerobically grow on a number of aromatic compounds, such as phenol, sodium benzoate, p-hydroxybenzoate, phenylacetate, benzene, ethylbenzene, benzylalcohol, and so on. In particular, it could mineralize up to 1,000 mg l(-1) phenol at room temperature (25 degrees C). The growth kinetics of strain EDP3 on phenol as a sole carbon and energy source at 25 degrees C can be described using the Haldane equation. It has a maximal specific growth rate (mu(max)) of 0.28 h(-1), a half-saturation constant (K(S)) of 1,167.1 mg l(-1), and a substrate inhibition constant (Ki) of 58.5 mg l(-1). Values of yield coefficient (Y(X/S)) are between 0.4 and 0.6 mg dry cell (mg phenol)(-1). Strain EDP3 has high tolerance to the toxicity of phenol (up to 1,000 mg l(-1)). It therefore could be an excellent candidate for the biotreatment of high-strength phenol-containing industrial wastewaters and for the in situ bioremediation of phenol-contaminated soils.
authors.affiliation: School of Life Sciences and Chemical Technology, Ngee Ann Polytechnic, 535 Clementi Road, Singapore 599489, Singapore. gan2@np.edu.sg
authors.forename: Anli
authors.initials: A
authors.lastname: Geng
authors.forename: Alwyn En Wei
authors.initials: AE
authors.lastname: Soh
authors.forename: Ci Ji
authors.initials: CJ
authors.lastname: Lim
authors.forename: Leslie Ching Thin
authors.initials: LC
authors.lastname: Loke
mesh_terms: D016954:Acinetobacter calcoaceticus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D000332:Aerobiosis; D001673:Biodegradation, Environmental; D003470:Culture Media; D004269:DNA, Bacterial / Q000032:analysis / Q000302:isolation & purification; D007220:Industrial Waste; D008969:Molecular Sequence Data; D019800:Phenol / Q000378:metabolism*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology*
chemical_list: D003470:Culture Media; D004269:DNA, Bacterial; D007220:Industrial Waste; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D019800:Phenol