Evaluation of biodegradation process of textile azo dye in solution by Aspergillus oryzae by UV-VIS and FTIR analysis

摘要

This research aims to evaluate the biodegradation process of the textile azo dye Direct Blue 71 (DB71) by the fungus Aspergillus oryzae, using the UV-VIS spectrophotometer and the FTIR to analyse the dye solution treated by fungus pellets form. The biodegradation assays were prepared with dye solution DB71, A. oryzae pellets and distilled water in pH 2.5. The samples were incubated and every 24 h a sample was used to analysis on UV-VIS spectrophotometer and to make a disk with KBr for analysis of FTIR. After analysing the spectra and the absorbance ratio values, it was observed that changes occurred during the first 48 h showing signs of biodegradation that was only confirmed after analysis of FTIR spectra. Therefore, the UV-VIS spectrophotometry coupled with FTIR proved to be an important tool in the analysis of biodegradation of contaminants.