Isolation of phenol-degrading strain and preliminary studies on its degrading characteristics

In order to investigate the biodegradation mechanisms of phenol by aerobic granular sludge,18 strains were isolated from the sludge using basal medium with phenol as sole carbon source and strain 1# which have high degradation efficiency was studied.This strain could endurance concentration of phenol up to 2000 mg/L when inoculated in medium with phenol as the sole energy and carbon source.The optimization experiments of phenol degradation with strain 1# showed that,with inoculum amount 3%,temperature 30 ℃,pH value 6.85,liquid volume in flask 100 mL and rate of shaking incubator 120 r/min,phenol with initial concentration 1000 mg/L could be degraded up to 95% after 24 h.Moreover,it was revealed that addition of glucose with low concentration(0.5~1.0 g/L)could promote growth of strain,thus increase the phenol removal.The colony morphology of strain 1# was circular,smooth and pinkish,and it was identified as Candida tropicalis according to the 23Sr DNA sequence analysis.