Isolation and Identification of Phenol Degrading Bacteria from Oil Refinery Effluents

Phenol and its derivatives are toxic to all living organism and are found in oil refinery wastewater. Isolation and identification of bacteria from oil refinery wastewater is important to identify aromatic compounds degrading bacteria. The aims of this study were isolation and identification of bacteria from Tehran oil refinery wastewater treatment system and determine amount of phenol degradation by these bacteria.

This experimental study was conducted by using two series of activated sludge samples collected from Tehran oil refinery wastewater treatment plant. Adaptation of bacteria to phenol was done by culturing in growth medium containing phenol at 30°C in incubator. After that isolation and identification of bacteria was done according to standard method. Isolated bacteria were cultured in growth medium containing different concentration (0.5- 1.2gL-1) of Phenol. Bacteria growth was assayed by measuring optical density at 600nm. Concentration of Phenol in the medium growth solution was measured by spectrophotometric method using 4- Amino antipyrine as color reagent at 510 nm.

Pseudomonas, Acintobacter, E.coli, Enterococcus and Enterobacter spps were isolated from oil wastewater treatment plant. Pseudomonas spp. completely removed 0.9gL-1 of Phenol, Acintobacter and E.coli removed 0.7 gL-1, Enterococcus and Enterobacter removed 0.5 gL-1 of Phenol from growth solution. 

Discussion and conculation:

 Pseudomonas spp. isolated from oil refinery wastewater treatment plant has highest phenol removal rate in shorter contact time than other isolated bacteria.