DEGRADATION OF PHENOLS BY THERMOPHILIC AND HALOPHILIC BACTERIA ISOLATED FROM A MARINE BRINE SAMPLE

Two thermophilic bacteria that degrade phenol, strains 401 and 501, were isolated from a brine sample from a submarine gas field. Strain 401 was identified as being Bacillus stearothermophilus. Strain 501 was tentatively identified as a previously unknown species in the family of Rhizobiaceae. Strains 401 and 501 completely degraded phenol at the concentrations of 1,000 and 700 mg/l, respectively, while growing on a nutrient broth at 50-degrees-C. Bacterial cells grown on a medium containing phenol degraded a variety of phenolic compounds. Strain 401 tolerated up to 10% NaCl, and strain 501 absolutely required seawater for growth and phenol degradation. Such thermophilic bacteria that tolerate salt and phenol might be useful for the treatment of industrial wastes containing phenols.