Atena Alirezaei Dizicheh - Department of Microbiology, Science and Research branch, Islamic Azad University, Tehran, Iran
Mansour Bayat - Department of Microbiology, Science and Research branch, Islamic Azad University, Tehran, Iran
Mahmood Alimohmmadi - Department of Environmental Health Engineering , School of Public Health, Tehran University of Medical Science, Tehran, Iran
Jamal Hashemi - Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Science, Tehran, Iran

Chlorophenols are the most toxic pollutants of water and wastewater. Since ۴-chlorophenol is a high soluble compound in water, it is found in water and wastewater abundantly. Because of high costs, high energy consumption and in some cases environmental inconsistency in chemical and physical removal methods, biochemical degradation of ۴-chlorophenol is very important. In the present study, ۱۳ strains of bacteria and ۶ strains of yeast and mold were purified and isolated from wastewater treatment plant (Imam Khomeini seaport, Mahshahr), which lasted about ۱۵ days. Then, the ability of each microorganism isolated in the presence of ۱۰۰ppm of ۴-chlorophenol was studied and two microbial species suitable for TY۱ and TY۲ were selected for use in mixed microbial culture. In this research, one of the most important factors affecting ۴-chlorophenol degradation was by mixed microbial culture including glucose concentration with ۲ and ۵g/l was investigated. After examination, the microbial strains suitable for TY۱ and TY۲ were able to completely remove the ۱۰۰ppm of ۴-chlorophenol, so that the TY۱ strain was removed completely after ۴۵ hours and by TY۲ strain after ۲۱ hours and also, using a mixture of TY۱ and TY۲ strains (۵۰/۵۰) and in the presence of ۲g/l glucose, ۱۰۰ppm of ۴-chlorophenol was completely removed after ۱۸ hours. The significance and impact of this study was the use of indigenous strains isolated from wastewater treatment plant in petroleum refineries and petrochemical industries for the biodegradation of chlorophenol.

۴-chlorophenol, wastewater, Degradation, Imam Khomeini seaport, petrochemical