Augmentation of dietary glucosylceramide hydrolysis by the novel bacterium Glucerabacter canisensis NATH-2371^T

The purpose of this study was to evaluate the effects of intragastrical administration of Glucerabacter canisensis NATH-2371^T on glucosylceramide (GluCer) digestion in mice. Although G. canisensis was unable to utilize starch and cellulose, coculture of G. canisensis with mouse fecal bacteria greatly increased GluCer hydrolysis in polysaccharide medium, indicating that G. canisensis grew in competition with other intestinal bacteria. Although most of the administered G. canisensis cells were detected in feces, some cells were present in the colorectum contents, which had GluCer-hydrolyzing activity. These results indicate that G. canisensis can viably transit through the mouse gut. Administration of G. canisensis to mice fed diets supplemented with GluCer or GluCer-containing foods significantly enhanced GluCer hydrolysis. Since G. canisensis did not show acute toxicity, it may be useful as a probiotic to augment GluCer hydrolysis in the large intestine. Abbreviations: GluCer: glucosylceramide; KPi: potassium phosphate buffer; C-M: chloroform-methanol.