[Simple method for production of conditions of general anaerobiosis]

The description is given of a modified method starting from the alkaline pyrogalol technique, described by Béerens and Tahon-Castel, for obtaining anaerobiosis in Petri dishes. The modification consists in: sealing the dishes with paraffin, adding of talcum in the reducing mixture instead of silica, and use of the ready prepared mixture ovar a period of at most 6 months. The method was tested against the reference method using suspensions of C. Oedematiens (species demanding strictly anaerobiosis conditions), C. histolyticum (somewhat less exigent) and C. perfringens spores (mean esigence), seeding on the surface of dishes with Willis-Hobbs medium. The comparative experiment, counting 30,941 colonies on 408 Petri dishes proved the value of the method proposed. The procedure was just as efficient in surface cultures of nonsporulate anaerobic germs.