title: Decolorization of Reactive Black-5 by Shewanella sp. in the Presence of Metal Ions and Salts.
abstract: In this study, effect of various metal ions and salts on biodecolorization of Reactive black-5, azoreductase activity, and growth of Shewanella sp. strain IFN4 was evaluated. Among the tested metals, Cr²⁺, Pb(²⁺, Ni²⁺, Fe²⁺, and Mn²⁺ did not inhibit the biodecolorization of reactive black-5, azoreductase activity and bacterial growth. Three metals (Cu²⁺, Zn²⁺, and Co²⁺) delayed the decolorization process without completely inhibiting the reaction and also suppressed the bacterial growth. However, no dye decolorization was observed in the presence of Cd²⁺ (10 mg L⁻¹). Furthermore, bacterium decolorized the dye at high concentration (15 mg L⁻¹) of mixed metal ions. Strain IFN4 was also able to decolorize the dye at 50 g NaCl L⁻¹ and 60 g Na₂SO₄ L⁻¹. NaCl was found to be more inhibitory to bacterial growth than Na₂SO₄and the reverse was observed for azoreductase activity. These findings suggest that strain IFN4 could be used in designing a bioreactor for the treatment of textile effluent.
authors.affiliation: Department of Environmental Sciences, University of Gujrat-Gujrat 50700, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Imran
authors.forename: Muhammad
authors.initials: M
authors.lastname: Arshad
authors.forename: Azeem
authors.initials: A
authors.lastname: Khalid
authors.forename: Sabir
authors.initials: S
authors.lastname: Hussain
authors.forename: Muhammad Waseem
authors.initials: MW
authors.lastname: Mumtaz
authors.forename: David E
authors.initials: DE
authors.lastname: Crowley
mesh_terms: D001673:Biodegradation, Environmental; D004305:Dose-Response Relationship, Drug; D008670:Metals / Q000008:administration & dosage / Q000494:pharmacology*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D009282:Naphthalenesulfonates / Q000737:chemistry*; D009601:Nitroreductases; D020592:Shewanella / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D008670:Metals; D009282:Naphthalenesulfonates; D014874:Water Pollutants, Chemical; D009247:NADH, NADPH Oxidoreductases; D009601:Nitroreductases; C021106:azoreductase; C063421:Remazol black B