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Indexed by:期刊论文

Date of Publication:2013-09-01

Journal:WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY

Included Journals:SCIE、EI、PubMed、Scopus

Volume:29

Issue:9

Page Number:1723-1730

ISSN No.:0959-3993

Key Words:Shewanella oneidensis MR-1; Sudan dye; Quinone; Humic acid

Abstract:Although there have been many studies on bacterial removal of soluble azo dyes, much less information is available for biological treatment of water-insoluble azo dyes. The few bacterial species capable of removing Sudan dye generally require a long time to remove low concentrations of insoluble dye particles. The present work examined the efficient removal of Sudan I by Shewanella oneidensis MR-1 in the presence of redox mediator. It was found that the microbially reduced anthraquinone-2,6-disulfonate (AQDS) could abiotically reduce Sudan I, indicating the feasibility of microbially-mediated reduction. The addition of 100 mu M AQDS and other different quinone compounds led to 4.3-54.7 % increase in removal efficiencies in 22 h. However, adding 5-hydroxy-1,4-naphthoquinone into the system inhibited Sudan I removal. The presence of 10, 50 and 100 mu M AQDS stimulated the removal efficiency in 10 h from 26.4 to 42.8, 54.9 and 64.0 %, respectively. The presence of 300 mu M AQDS resulted in an eightfold increase in initial removal rate from 0.19 to 1.52 mg h(-1) g(-1) cell biomass. A linear relationship was observed between the initial removal rates and AQDS concentrations (0-100 mu M). Comparison of Michaelis-Menten kinetic constants revealed the advantage of AQDS-mediated removal over direct reduction. Different species of humic acid could also stimulate the removal of Sudan I. Scanning electronic microscopy analysis confirmed the accelerated removal performance in the presence of AQDS. These results provide a potential method for the efficient removal of insoluble Sudan dye.