Biodegradation of Higher Concentration Phenol by Pseudomonas aeruginosa HS-D38

Phenol is an important and common environmental pollutant. In this study, Pseudomonas aeruginosa HS-D38 strain was used to degrade phenol, and the degradation characteristics were investigated. Results indicated that HS-D38 strain could degrade phenol and utilize it as the sole carbon, nitrogen and energy source. UV-visible spectra analysis showed that 300 mgL^-1 phenols could be completely degraded within 10 h by HS-D38 strain after an initial lag phase of 2 h, and the peak decreased gradually with the degradation of phenol by HS-D38. At the same time, an increase of OD₆₀₀ values in the culture was also observed. Phenol could be mineralized at higher concentration of 500 mgL^-1 by HS-D38 strain, whereas the degradation did not occur when the concentration was exceeded 700 mgL^-1 even after 72 h. A key intermediate was detected analyzing the degradation solution with HPLC and it was identified to p-hydroxybenzoic acid. The peaks disappeared after 15 h indicating intermediates were also degraded by HS-D38 strain and the metabolism proceeded through the p-hydroxybenzoic acid pathway.