Dioctahedral smectite neutralization activity of Clostridium difficile and Bacteroides fragilis toxins in vitro.

The neutralization activity of dioctahedral smectite for ten toxigenic Clostridium difficile and eight enterotoxigenic Bacteroides fragilis strains was studied using McCoy and HT 29/C1 cell lines, respectively. Minimalization of the cytopathic effect of C. difficile toxin B on McCoy cell lines by dioctahedral smectite dissolved in PBS was observed. After incubation with dioctahedral smectite the toxic effects of B. fragilis enterotoxins on HT/29C1 (human colon adenocarcinoma cell line) were eliminated. Best neutralization of B. fragilis toxin was achieved using dioctahedral smectite dissolved in BHI.