MOISTURE ACTIVITY ON GERMINATION 



49 



Table I 

 Germination of Old Spores of B. cereus var. terminalis in sucrose 



% 

 Sucrose 

 

 19 

 20 

 21 

 22 

 25 

 29 

 30 

 31 

 32 



Moisture 

 Activity 

 100.00 

 98.72 

 98.63 

 98.54 

 98.43 

 98.11 

 97.72 

 97.60 

 97.47 

 97.34 



Klett 



Drop 



100 



98 



97 



77 



72 



66 



41 



40 



4 







ty), whereas freshly prepared nonrefrigerated spores germinated in 35% 

 sucrose (96.8% moisture activity). Spores of Bacillus subtilis and Bacillus 

 megatherium were also prepared and tested by this technique to see if species 

 differences existed. Unrefrigerated spores of B. subtilis ceased germination 

 above 34% sucrose (97.0% moisture activity), while for B. megatherium 

 the limit was 38% sucrose (96.3%) moisture activity). Spores of Clostridium 

 hotulinum Type B were also examined, both in 2% thiotone water and in a 

 solution containing L-alanine, L-phenylalanine, and L-arginine, which has 

 been found to satisfy the germination requirements for this organism. In 

 both media the highest concentration of sucrose supporting germination was 

 31% (97.5% moisture activity) (see Table II). 



Table II 

 Moisture Limits for Germination 



Organism 

 B. cereus var. terminalis 

 B. cereus var. terminalis 

 B. cereus var. terminalis 

 B. cereus var. terminalis 

 B. subtilis 

 B. megatherium 

 CI. botulinum 



Condition 



Old 



Old 



Fresh. Ref'd 



Unref'd 



Unref'd 



Unref'd 



Old 



