Abstract
Spores ef Clostridium botulinum type A 190 were germinated rapidly under suitable conditions in a chemically defined medium consisting of 5mM L-alanine, 10mM L-laetate, 60mM bicarbonate, and 100mM phosphate buffer (pH 6.7). Heat activation did occur only when spores were heated at 70°C for 10min in the medium or in a phosphate buffer (250mM, pH 6.7), but not when spores were heated sublethally in water. Germination took place under both aerobic and anaerobic conditions regardless of Eh levels. Maximum germination (more than 90% in 3hr) in the defined medium was obtained in the pH range of 6.7 to 7.2 and in the incubation temperature of 30° or 37°C. Some α-hydroxy acids, including lactate and its analogues, as well as thiogllycolate were found to be effective in promoting the germination in combination with L-alanine and bicarbonate.
