International Journal of Water Resources and Arid Environments 9(1): 21-36, 2020 ISSN 2079-7079 © PSIPW, 2020 Corresponding Author: Prof. Dr. Wafaa M. Abd El-Rahim, Department of Agriculture Microbiology, National Research Centre, Dokki, Cairo, Egypt. 32 El Bohouth st.(former El-Tahrir st.), Dokki, Cairo, Egypt. P.O. Box: 12622. Mob: +201001162641, Tel/Fax:+202-37601036, E-mail: wafaa10m@hotmail.com, wafaa10m@gmail.com. 21 Assessment of Fungal Production of Laccases and Peroxidase Required as Potential Method for Biodegradation of Simulated Industrial Wastewater Containing Textile Green Azo Dye Wafaa M. Abd El-Rahim, Hassan Moawad and Ahmed Z. Abdel Azeiz 1 1 2 Department of Agriculture Microbiology, National Research Centre, Dokki, Cairo, Egypt 1 College of Biotechnology, Misr Univ. for Science and Technology, Egypt 2 Abstract: The textile dye residues represent a growing threat to the surrounding environment of this vital industry. Therefore, the appropriate technology for the removal of dye residues from industrial effluents is an important task. One of these technologies is based on the bioremediation that depends on using certain microorganisms to remove these toxic wastes. It is well known that the microbial agents perform all biological transformations through immense enzymatic tools existing within the intact microbial cells. The use of the specific enzymes required for breakdown of certain industrial wastes can reduce the time of residues removal and consequently the cost of the process. In this study the production of two fungal enzymes namely laccases and peroxidases were assessed. To study these enzymes fifteen fungal strains were first screened for their growth on mineral salt medium supplemented with 0.5g/L of green azo dyes as sole source of carbon. The strains could grow on the above mentioned medium that indicates the production of the enzymes necessary for biodegradation of the dye and the support of biodegradation products for the growth of the fungal strains. The efficiency of the fungal strains production of the two important enzymes contributing to the azo dye biodegradation was tested on potatoes dextrose broth medium, throughout 15 days of incubation. In general the production of peroxidases was higher on potato dextrose medium than on mineral salt medium both supplemented with the green azo dye. The amounts of enzyme production were different from one strain to another. The fungal strains produced more laccases and peroxidases on potato dextrose medium than those produced on mineral salt medium. The most promising fungal strains for the production of the two enzymes are strains No. 1 and 2. In this study the direct response of fungal cells to the presence of azo dye in the medium was studied through tracking the fungal cell microscopy image analysis. The electron micrographs showed obvious differences in the cell wall and most of the cell components. The cell wall thickness after contact with the dye solution was almost doubled; moreover new components inside the cells were formed which might be due to the induction of specific enzymes such as the ligninolytic ones. Key words: Legninolytic enzyme Fungal strains Bioremediation Azo textile dye residues INTRODUCTION Egypt's lifeline as the source of all water required for Dyes and chemicals widely used in textile, paper, human consumption [1, 2]. Due to the chemical stability of plastic, food and cosmetic industries are easily recognized the dye components, conventional wastewater treatment pollutants. Its presence, even in very low concentration, technologies are often ineffective for handling wastewater is highly visible and affects aquatic life and cause many containing synthetic textile dyes [3]. Considerable diseases. The chemical pollutants discharged in textile research has been done on color removal from industrial industry in general and dye in particular if released into effluents to decrease their impact on the environment. the surrounding environment without treatment will These technologies include adsorption onto inorganic or eventually contaminate the Nile River, which represent organic matrices, decolorization by photo-catalysis or agriculture sector, generation energy, industrial uses and