STABILITY OF SPORES OF BACILLUS-CREUS STORED ON SILICA-GEL

Spores of four different strains of Bacillus cereus were stored on sil icagel at 22-degrees-C and in physiological saline solution at -20-deg rees-C for a period of 260 days. At different intervals the spores wer e tested for survival, heat sensitivity and capacity to germinate. The re was no clear change in any of the parameters tested, so storage on silicagel can be a good alternative for storage as a frozen suspension . Spores stored in this way can easily be exchanged for reference mate rial and used for microbiological challenge testing.