title: Enhancement of antibiotic activity against Staphylococcus aureus by exposure to hyperbaric oxygen.
abstract: Growth of Staphylococcus aureus ATCC 6538P was studied in stationary broth cultures (11 mm deep) exposed to hyperbaric oxygen (100% O(2) at 3 atm absolute). The minimal inhibitory concentration (MIC) of the following antibiotics was determined after exposure to high-pressure oxygen (HPO) for 3, 6, and 12 hr: penicillin, streptomycin, tetracycline, oxytetracycline, kanamycin, and cephalothin. Logarithmic growth during exposure to HPO was retarded 60%. Air at 3 atm absolute did not retard growth. The longer the exposure of tube dilution tests to HPO, the lower the MIC. Regardless of the antibiotic used, MIC values relative to 100% for unexposed controls were similar for given exposures, and averaged 73% after 3 hr of exposure to HPO, 53% after 6 hr, and 34% after 12 hr. Similar enhancement with HPO and an iodophor suggests occurrence of a general phenomenon with antibacterial agents. Although HPO alone is primarily bacteriostatic, combined therapy with antibiotics and HPO may be useful against bacterial infections because the therapeutic effectiveness of a maximal dosage of antibiotic could be increased.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002512:Cephalothin / Q000494:pharmacology; D007612:Kanamycin / Q000494:pharmacology; D010100:Oxygen / Q000494:pharmacology*; D010118:Oxytetracycline / Q000494:pharmacology; D010406:Penicillins / Q000494:pharmacology; D011312:Pressure; D013210:Staphylococcus / Q000254:growth & development*; D013307:Streptomycin / Q000494:pharmacology; D013752:Tetracycline / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D010406:Penicillins; D007612:Kanamycin; D013752:Tetracycline; D002512:Cephalothin; D010100:Oxygen; D010118:Oxytetracycline; D013307:Streptomycin