title: Decolorization of dyehouse effluent and biodegradation of Congo red by Bacillus thuringiensis RUN1.
abstract: A dye-decolorizing bacterium was isolated from a soil sample and identified as Bacillus thuringiensis using 16S rRNA sequencing. The bacterium was able to decolorize three different textile dyes, namely, Reactive blue 13, Reactive red 58, and Reactive yellow 42, and a real dyehouse effluent up to 80-95% within 6 h. Some non-textile industrially important dyes were also decolorized to different extents. Fourier transform infrared spectroscopy and gas chromatography-mass spectrometer analysis of the ethyl acetate extract of Congo red dye and its metabolites showed that the bacterium could degrade it by the asymmetric cleavage of the azo bonds to yield sodium (4- amino-3-diazenylnaphthalene-1-sulfonate) and phenylbenzene. Sodium (4-amino-3-diazenylnaphthalene-1-sulfonate) was further oxidized by the ortho-cleavage pathway to yield 2- (1-amino-2-diazenyl-2-formylvinyl) benzoic acid. There was induction of the activities of laccase and azoreductase during the decolorization of Congo red, which suggests their probable role in the biodegradation. B. thuringiensis was found to be versatile and could be used for industrial effluent biodegradation.
authors.affiliation: Department of Chemical Sciences, Redeemer's University, PMB 3005 Redemption City, Ogun State, Nigeria. olukanni_olumide@yahoo.com
authors.forename: Olumide David
authors.initials: OD
authors.lastname: Olukanni
authors.forename: Akinniyi A
authors.initials: AA
authors.lastname: Osuntoki
authors.forename: Ayodeji Olushola
authors.initials: AO
authors.lastname: Awotula
authors.forename: Dayanand C
authors.initials: DC
authors.lastname: Kalyani
authors.forename: George Olabode
authors.initials: GO
authors.lastname: Gbenle
authors.forename: Sanjay P
authors.initials: SP
authors.lastname: Govindwar
mesh_terms: D001413:Bacillus thuringiensis / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001711:Biotransformation; D016000:Cluster Analysis; D004396:Coloring Agents / Q000378:metabolism*; D003224:Congo Red / Q000378:metabolism*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D008401:Gas Chromatography-Mass Spectrometry; D053858:Metabolic Networks and Pathways; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D004396:Coloring Agents; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D003224:Congo Red