Removal of phenol and zinc byCandidaisolated from wastewater for integrated biological treatment

Abstract

The present study aims to evaluate the removal of phenol and zinc by Candida strains isolated from sludge and wastewater. It also aims to select candidates for biosorption and bioreduction to improve the traditional treatment process of wastewater and produce reclaimed water for irrigation. Forty-one Candida strains (12 Candida tropicalis ,1 3Candida lipolytica ,6 Candida maltosa ,1 0Candida parasopilis) from sludge and wastewater during treatment of sewage water were screened for their Zn biosorption and phenol removing potential. Four C. tropicalis, 3 C. lipolytica ,2 C. maltose and 6 C. parasopilis strains demonstrated the highest final population (>7 log CFU/ml) after 3 h of exposure to low pH and temperature. The majority of the tested strains were resistant and exhibited partial phenol degrading up to 700 μg/ml. Scanning electron microscopy of Candida indicated that there was neither damage in the cells nor signs of irregular wrinkled outer surface of cells when treated with phenol or Zn compared to the control. These strains are good candidates for further investigation within different sewage treatment plant systems to elucidate their potential biodegradation and bioabsorption of hazard benefits in the system used for treating wastewater.