Biodegradation of phenol by Rhodococcus phenolicus isolated from Kitchener wastewater drain, Kafr El-Sheikh, Egypt

Abstract

Water contamination and pollution present major environmental issues that face our world nowadays. One of the most harmful water pollutants are phenolic compounds, which are abundant in industrial wastewater, and can be accumulated in the water and sediment where aquatic organisms hunt and forage. Therefore, the aim of this study was to isolate an effective phenol-degrading microorganism and employ it in removing phenol from household wastewater. Thirty one bacterial isolates were obtained from Kitchener wastewater drain, Kafr El-Sheikh, Egypt which is known for its highly industrial wastewater contamination sites able to utilize phenol as a sole carbon source at 1000 mg/L. Microbiological and physicochemical analyses were performed on the wastewater sample from the Kitchener drain. The indigenous phenol-degrading bacterial isolates were examined for their diversity using BOX-PCR fingerprinting and revealed a high genetic diversity. The bacterial isolates were evaluated for their ability to degrade phenol at 1000 mg/L for 11 days using mineral salt medium supplemented with phenol as a sole carbon source, monitoring the changes in their growth density, CFU, and the remaining phenol content after 0, 2, 4, 6, 8, and 11 days. The highest phenol biodegradation rate was recorded by a Gram positive bacterial isolate, exhibiting 96% degradation ability. The selected isolate was identified using 16S rRNA gene sequence analysis, revealing 99.87% similarity with the species Rhodococcus phenolicus. The sequence was deposited in the NCBI GenBank database with accession number PP819386.