caa a22 4500 606169156 CHVBK 20210128100710.0 cr unu---uuuuu 210128e20150801xx s 000 0 eng 10.1007/s10098-014-0869-6 doi (NATIONALLICENCE)springer-10.1007/s10098-014-0869-6 Degradation of azo dyes by laccase: biological method to reduce pollution load in dye wastewater [Elektronische Daten] [J. Kanagaraj, T. Senthilvelan, R. Panda] Laccases are the oldest with low substrate specificity enzymes used for degradation of various compounds, especially, dyes. In the present investigation, the cell-free extract of laccase enzyme is applied to degrade azo dyes used in leather processing. The enzyme degrades the azo dyes rapidly at optimum growth conditions of pH 7.0, temperature 37°C and incubation duration of 72h. Better production of the enzyme was achieved with dextrose, yeast extract, acetone, copper sulphate and orange peel. The molecular weight of laccase was found to be 63kDa. The percentage of degradation is found to be 96.4% for CI Acid black 210 and 92.2% for the CI Acid black 234. Ultraviolet-visible spectral analysis indicates the presence of peaks in the visible region confirming the complete degradation of the dye sample. Fourier transform-infrared spectroscopy analysis shows the transformation of N=N into either N2 or NH3 and then into biomass. The mass spectra analysis shows conversion of azo dye to final product through various intermediates with their respective molecular weights. Chemical oxygen demand (COD) and biochemical oxygen demand (BOD) analysis reveal the reduction of pollution load more than 92% in the experimental process while maintaining BOD/COD ratio to about 30%. Springer-Verlag Berlin Heidelberg, 2014 Azo dyes nationallicence Laccase enzyme nationallicence Degradation nationallicence FT-IR and mass spectra analyses nationallicence Pollution reduction nationallicence Kanagaraj J. Leather Processing Division, CSIR-CLRI, Adyar, 600020, Chennai, India aut Senthilvelan T. Leather Processing Division, CSIR-CLRI, Adyar, 600020, Chennai, India aut Panda R. Chemical Engineering Division, CSIR-CLRI, Adyar, 600020, Chennai, India aut Clean Technologies and Environmental Policy Springer Berlin Heidelberg 17/6(2015-08-01), 1443-1456 1618-954X 17:6<1443 2015 17 10098 https://doi.org/10.1007/s10098-014-0869-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10098-014-0869-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kanagaraj J. Leather Processing Division, CSIR-CLRI, Adyar, 600020, Chennai, India aut NATIONALLICENCE 700 1- Senthilvelan T. Leather Processing Division, CSIR-CLRI, Adyar, 600020, Chennai, India aut NATIONALLICENCE 700 1- Panda R. Chemical Engineering Division, CSIR-CLRI, Adyar, 600020, Chennai, India aut NATIONALLICENCE 773 0- Clean Technologies and Environmental Policy Springer Berlin Heidelberg 17/6(2015-08-01), 1443-1456 1618-954X 17:6<1443 2015 17 10098