Evaluation of in vitro efficacy for decolorization and degradation of commercial azo dye RB-B by Morganella sp. HK-1 isolated from dye contaminated industrial landfill.
Reactive Black-B (RB-B) - one of the multi-sulphonated reactive azo dye - is being used extensively in textile as well as paper industries. Reactive azo dyes comprise of a significant group of synthetic compounds categorized as xenobiotics and its abatement from the environment still remains a challenge. In the present study, a newly isolated indigenous bacterial strain Morganella sp. HK-1 was exploited for its ability to decolorize and degrade RB-B dye. The isolate completely degraded RB-B (20 g L(-1)) within 24h under static conditions. Furthermore, the visible and FTIR spectral analysis established the bio-degradation of RB-B. The degraded metabolites of RB-B by Morganella sp. HK-1 were identified by GC-MS analysis as disodium 3,4,6-triamino-5-hydroxynaphthalene-2,7-disulfonate, 4-aminophenylsulfonylethyl hydrogen sulfate, naphthalene-1-ol, aniline and benzene. Based on this information, a putative pathway of degradation of RB-B by Morganella sp. HK-1 has been proposed. This study is the first report on elucidation of mechanism of bacterial degradation of RB-B dye. Furthermore, phytotoxicity, genotoxicity and aquatic acute toxicity studies of the parent dye and the bio-degraded dye products revealed drastic reduction in the toxicity of metabolites as compared to the parent dye. This implies that the biotreatment of the dye is of non-toxic nature. This study thus indicates the effectiveness of Morganella sp. HK-1 for the treatment of textile effluents containing sulphonated azo dyes.
Department of Microbiology, P.D. Patel Institute of Applied Sciences, Charotar University of Science and Technology, Changa 388 421, Gujarat, India. Electronic address: Hilorpathak.mi@charusat.ac.in.
Hilor
H
Pathak
Department of Microbiology, P.D. Patel Institute of Applied Sciences, Charotar University of Science and Technology, Changa 388 421, Gujarat, India.
Dhaval
D
Soni
Department of Integrated Biotechnology, Ashok and Rita Patel Institute of Integrated Studies and Research in Biotechnology and Allied Sciences, Sardar Patel University, New Vallabh-Vidyanagar 388 121, Gujarat, India. Electronic address: kishorchauhan@aribas.edu.in.
Kishor
K
Chauhan
D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism; D001673:Biodegradation, Environmental; D003116:Color; D004396:Coloring Agents / Q000378:metabolism* / Q000633:toxicity; D007887:Fabaceae / Q000187:drug effects / Q000254:growth & development; D007220:Industrial Waste; D020596:Morganella / Q000378:metabolism*; D009152:Mutagenicity Tests; D009282:Naphthalenesulfonates / Q000378:metabolism* / Q000633:toxicity; D009348:Nematoda / Q000187:drug effects; D019697:Onions / Q000187:drug effects / Q000235:genetics; D010088:Oxidoreductases / Q000378:metabolism; D013784:Textiles; D023382:Toxicity Tests, Acute; D064091:Waste Disposal Facilities; D014874:Water Pollutants, Chemical / Q000378:metabolism* / Q000633:toxicity
D001426:Bacterial Proteins; D004396:Coloring Agents; D007220:Industrial Waste; D009282:Naphthalenesulfonates; D014874:Water Pollutants, Chemical; D010088:Oxidoreductases; C063421:Remazol black B
Degradation pathway; Genotoxicity; Morganella sp.; Phytotoxicity; Sulphonated reactive azo dye