Efficient decolorization of textile dyes by alkaline protease producing bacterial consortia

Abstract

Alkaline protease producers were isolated from poultry farm waste and sea water samples and identified based on a polyphasic approach including 16S rRNA partial gene sequences as <em>Bacillus aryabhattai </em> P1, <em>Bacillus firmus</em> P2, <em>Bacillus</em> sp. P4, <em>Bacillus cereus</em> P5, <em>Bacillus clausii </em>P6, <em>Alkalibacterium kapii</em> MGR70, <em>Halobacillus alkaliphilus</em> MGR92, <em>Alteromonas halophila</em> MGR98 and <em>Bacillus halodurans</em> MGR125. Beside alkaline protease production, these isolates have also shown textile dye decolorization capability. Therefore two consortiums namely, PF1 and SW2 were developed to achieve maximum decolorization of the textile dyes, DR-81 and DO-34. The consortium SW2 has shown highest decolorization of Direct Red-81 (68.88 %) and Direct Orange-34 (70.78 %) at a concentration of 5 g/l after 144 h.