Bioremediation of Dyestuff Compounds using Indigenous Microorganism in a Bioreactor

Dyes are synthesized in a reactor, filtered, dried, blended with other color additives to produce the final product. The liquid effluent resulting from the manufacture of colored dye contains toxic organic residues and inorganic compounds. The present treatment technology involves: neutralization, flocculation, coagulation-settling, carbon adsorption, detoxification of organics by oxidation and biological treatments. In spite of the present treatment, the discharge effluent contains the color residual toxic compounds. In the present research study the dye effluent discharged at the waste disposal site has been characterized for physico-chemical and microbial characterization. The microorganisms adapted at contaminated sites have been isolated and cultured to use as a biomass for bioremediation of identified toxic organic compounds present in dye effluent. GC-MS has identified -octadecene; 5-Eicosene, (E)-; Di (2-ethylhexyl) phthalate; 1-nonadecene; Butyl-2-ethylhexyl phthalate; 5-Chloro-1,3-benzodioxole; 2-Oxazolidinone, 3, -dimethyl-5- phthalate; 1-Phenyl-5-methylnona-1, 3, 4-triene; and 2,2-Dimethyl-N-(3-methylpenyl) propanamide dye compounds in discharge effluents. The bioremediation of dye stuff-discharged effluent was carried out in a laboratory bioreactor using indigenous microbial consortium under controlled environmental conditions. The biodegradation studied at an interval of every hour for a day and thereafter each day for a period of 21 days, till the complete biodegradation takes place. Biodegradation has been studied using GC-MS; the intermediate compounds were found to be biodegraded into pthalic acid - a non toxic compound. The indigenous microbial consortium developed was found effective and efficient to biodegrade dye compounds into environmental friendly compounds. (C) 2012 The Authors. Published by Elsevier B.V. Selection and/or peer review under responsibility of Asia-Pacific Chemical, Biological & Environmental Engineering Society