The Clostridium difficile toxins, toxin A and Toxin B were characterised in respect to the influence of glucose and incubation period on release of toxins, cytotoxic activities of the toxins in Verocell line and the immunogenic potential of C. difficile toxoids. A gradual increase in protein concentrations was observed in the cell free supernatants of toxin A and B positive C. difficile isolate with increase in incubation period and found to reach the highest at 48 hr of incubation, ., µg/µl and µg/µl, respectively. Release of C. difficile toxins in the culture supernatants was suppressed by glucose supplement in the nutrient media. Both the partially purified toxins were found to be cytotoxic for vero cells at both 1:10 and 1:100 dilutions. Cytotoxic activity of toxin B was more prominent than toxins A. However, similar immune-protective efficacy () was exhibited by both the toxoid preparations (Toxoid A and B) in immunized animals against homologous challenge with CFU, while percent protection against CFU of homologous strains of C. difficile was observed in both the groups, immunized separately with toxoid A and B. The affected mice, following challenge with CFU dose could show clinical symptoms, suggestive of intestinal disorder, without mortality. However, all the mice of control group died on 48 hr of post challenge with both x 108 and / dose of homologous strain of C. difficile. | Characterization of toxins in the culture supernatants of Clostridium Difficile and their immunogenic potential in mice
