title: Reductive behaviour of acid azo dye based wastewater: Biocatalyst activity in conjunction with enzymatic and bio-electro catalytic evaluation.
abstract: Present study illustrates the significance of biocatalyst's reductive behaviour in the degradation of dye molecules using glucose as co-substrate. An anaerobic system was operated at a dye concentration of 50mg/l with an organic loading rate (OLR) of 1.36 kg COD/m(3)-day. Decolourization and COD removal efficiencies were observed to be 42% and 48% respectively. Azo reductase (18.9 U) and dehydrogenase enzyme (1.4 μg/ml) activities showed increment with operation time. Anaerobic microenvironment showed dye reduction converting them into aromatic amines. The presence of mediators viz., cytochromes, quinines and Fe-S proteins depicted in the cyclic voltammetry profiles played a crucial role in transfer of electrons for the reduction of dye molecules. Bio-electro kinetic profiles obtained through Tafel analysis showed persistent reduction behaviour, which is in good correlation with dye degradation in the anaerobic microenvironment.
authors: Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India.
authors: S
authors: S
authors: Sreelatha
authors: Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India.
authors: C
authors: C
authors: Nagendranatha Reddy
authors: Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India.
authors: G
authors: G
authors: Velvizhi
authors: Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India. Electronic address: vmohan_s@yahoo.com.
authors: S
authors: S
authors: Venkata Mohan
mesh_terms: D001391:Azo Compounds / Q000032:analysis*; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D002384:Catalysis; D003116:Color; D004563:Electrochemistry / Q000379:methods; D004583:Electrons; D004798:Enzymes / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000379:methods
chemical_list: D001391:Azo Compounds; D004798:Enzymes; D010088:Oxidoreductases; D010100:Oxygen; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Anaerobic treatment; Azo reductase; Dehydrogenase activity: cyclic voltammetry; Redox mediators