Biodegradation of Cibacron Redazo Dye and Industrial Textile Effluent by Pseudomonas aeruginosa Immobilized on Chitosan-Fe2O3 Composite
Nashwa A. H. Fetyan *
Soils, Water and Environment Research Institute, Agricultural Research Center, Giza, Egypt
A. Z. Abdel Azeiz
College of Biotechnology, Misr University for Science and Technology (MUST), 6th October City, Egypt
I. M. Ismail
Department of Microbial Molecular Biology, Agricultural Genetic Engineering Research Institute (AGERI), ARC, Giza, Egypt
T. M. Salem
Soils, Water and Environment Research Institute, Agricultural Research Center, Giza, Egypt
*Author to whom correspondence should be addressed.
Abstract
A bacterial strain (Pseudomonas aeruginosa) having a high capacity for rapid decolourization of the azo dye Cibacron Red was isolated and identified by 16s-rRNA gene sequencing method. The decolorization of cibacron reactive red by free cell under experimental conditions was investigated. At initial dye concentration of 100 ppm, the maximum decolorization percentage (89%) was achieved at pH7, 37ºC under static conditions after 72 h of incubation. The bacterial cells were immobilized on chitosan-magnetite nanoparticles by using glutaraldehyde as a cross-linker. The immobilized cells were used for decolorization of both reactive red dye solution and textile industrial wastewater; a complete decolorization (100%) was achieved after 2 h and 12 h for each treatment, respectively. The dye biodegradation products were identified by GC/MS analysis and determination of laccase, peroxidase and dioxygenase enzyme activities in the bacterial supernatant. The obtained results from this work are expected to be a useful reference for development of effective decolorization bioprocesses utilizing immobilized bacterial cells as a biocatalyst and also to demonstrate feasible operation strategies to utilize the immobilized-cell as a fixed bed for efficient decolorization of dye-laden wastewaters.
Keywords: Pseudomonas aeruginosa, Cibacron Red, azo dye, textile wastewater, biodegradation