The different media medium 1 (Sucrose / yeast extract broth medium (Bormann et al., 1998), medium 2 (nutrient broth medium (Atlas, 1997), medium 3 (Bänziger and Tobler 2001), medium 4 (synthetic medium, Burdman et al., 1998) were used. 100 ml of each previous media were sterilized at 121 oC for 20 min and inoculated with 1ml of inoculum containing 108 cfu / ml (sucrose/yeast extract medium, 108 cfu / ml, incubated at 30oC and 150 rpm for 3 days) of B. cereus.