title: Biotransformation and Detoxification of Xylidine Orange Dye Using Immobilized Cells of Marine-Derived Lysinibacillus sphaericus D3.
abstract: Lysinibacillus sphaericusD3 cell-immobilized beads in natural gel sodium alginate decolorized the xylidine orange dye 1-(dimethylphenylazo)-2-naphthol-6-sulfonic acid sodium salt in the laboratory. Optimal conditions were selected for decolorization and the products formed were evaluated for toxicity by disc diffusion assay against common marine bacteria which revealed the non-toxic nature of the dye-degraded products. Decolorization of the brightly colored dye to colorless products was measured on an Ultra Violet-Vis spectrophotometer and its biodegradation products monitored on Thin Layer Chromatographic plate and High Performance Liquid Chromatography (HPLC). Finally, the metabolites formed in the decolorized medium were characterized by mass spectrometry. This analysis confirms the conversion of the parent molecule into lower molecular weight aromatic phenols and sulfonic acids as the final products of biotransformation. Based on the results, the probable degradation products of xylidine orange were naphthol, naphthylamine-6-sulfonic acid, 2-6-dihydroxynaphthalene, andbis-dinaphthylether. Thus, it may be concluded that the degradation pathway of the dye involved (a) reduction of its azo group by azoreductase enzyme (b) dimerization of the hydrazo compound followed by (c) degradation of monohydrazo as well as dimeric metabolites into low molecular weight aromatics. Finally, it may be worth exploring the possibility of commercially utilizingL. sphaericusD3 for industrial applications for treating large-scale dye waste water.
authors.affiliation: Bioorganic Chemistry Lab., Chemical Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula 403004, Goa, India. dprabha@nio.org.
authors.forename: Prabha
authors.initials: P
authors.lastname: Devi
authors.affiliation: Bioorganic Chemistry Lab., Chemical Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula 403004, Goa, India. solima@nio.org.
authors.forename: Solimabi
authors.initials: S
authors.lastname: Wahidullah
authors.affiliation: Bioorganic Chemistry Lab., Chemical Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula 403004, Goa, India. sfarhan512@gmail.com.
authors.forename: Farhan
authors.initials: F
authors.lastname: Sheikh
authors.affiliation: Bioorganic Chemistry Lab., Chemical Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula 403004, Goa, India. rpereira@nio.org.
authors.forename: Rochelle
authors.initials: R
authors.lastname: Pereira
authors.affiliation: CSIR-Indian Institute of Integrative Medicine, Mumbai 400053, India. nanarkhede@iiim.ac.in.
authors.forename: Niteen
authors.initials: N
authors.lastname: Narkhede
authors.affiliation: Bioorganic Chemistry Lab., Chemical Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula 403004, Goa, India. divya.amonkar@nio.org.
authors.forename: Divya
authors.initials: D
authors.lastname: Amonkar
authors.affiliation: Bioorganic Chemistry Lab., Chemical Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula 403004, Goa, India. supriyatilvi@nio.org.
authors.forename: Supriya
authors.initials: S
authors.lastname: Tilvi
authors.affiliation: Bioorganic Chemistry Lab., Chemical Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula 403004, Goa, India. ram@nio.org.
authors.forename: Ram Murthy
authors.initials: RM
authors.lastname: Meena
mesh_terms: D059001:Aquatic Organisms / Q000378:metabolism*; D001391:Azo Compounds / Q000378:metabolism; D001407:Bacillus / Q000378:metabolism* / Q000502:physiology*; D001673:Biodegradation, Environmental; D001711:Biotransformation / Q000502:physiology*; D018914:Cells, Immobilized / Q000382:microbiology*; D004396:Coloring Agents / Q000378:metabolism*; D007220:Industrial Waste; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D009282:Naphthalenesulfonates / Q000378:metabolism; D009601:Nitroreductases; D062065:Wastewater
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D007220:Industrial Waste; D009247:NADH, NADPH Oxidoreductases; D009282:Naphthalenesulfonates; D009601:Nitroreductases; D062065:Wastewater; C026497:2-naphthol-6-sulfonic acid; C021106:azoreductase
keywords: alginate-immobilized bacteria; analytical biotechnology; biotechnological application; sponge-associated bacteria