Efficiency of various bile salt preparations for stimulation of Clostridium difficile spore germination

Taurocholate, desoxycholate, and cholate stimulated germination of Clostridium difficile spores in broth medium and enhanced recovery of C. difficile spores on a selective agar medium. Desoxycholate and some crude taurocholate preparations also inhibited multiplication of vegetative cells. At a concentration of 1.2 X 10(-2) M, sodium cholate inhibited multiplication of vegetative cells, but at concentrations of 1.2 X 10(-3) to 2.4 X 10(-3) M, it stimulated germination without inhibiting cell multiplication. Thus, pure sodium taurocholate and sodium cholate may effectively be incorporated in cefoxitin-cycloserine-fructose agar, whereas some crude preparations of sodium taurocholate decrease recovery on this medium.