Use of D-cycloserine bitartarate for selective isolation of Clostridia
Takács, J.; Imreh, E.Z.
Acta Veterinaria Academiae Scientiarum Hungaricae 25(4): 283-289
1975
ISSN/ISBN: 0001-7205 PMID: 1233872 Document Number: 82943
D-Cycloserine bitartarate was tested for growth inhibition in blood agar and in sulfite agar medium containing egg-yolk emulsion, with special regard to the selective isolation of various Clostridium spp. for diagnostic purposes. At 800 .mu.g/ml concentration, D-cycloserine depressed the growth of C. perfringens strains and blocked that of C. histolyticum. At 600 .mu.g/ml D-cycloserine concentration in sulfite agar containing egg-yolk emulsion and 20 g/l agar, all Clostridium spp. except C. perfringens grew readily and displayed undisturbed lecithinase, lipase and sulfite-reduction activities characteristic of the species. C. perfringens strains grew only when the concentration of the inhibitor was reduced to 400 .mu.g/ml and the incubation temperature was maintained at 46 .+-. 0.5.degree. C, while the outgrowth of the accompanying flora was depressed by the inhibitor. C. botulinum and C. perfringens are readily detected if blood agar plates with 600 .mu.g/ml D-cycloserine and sulfite agar plates containing egg-yolk emulsion and 600 or 400 .mu.g/ml (C. perfringens) D-cycloserine are used simultaneously. Colonial morphology and hemolysis pattern were observed on blood agar; lecithinase and lipase activity were observed on sulfite agar containing egg-yolk.