Metabolism of Oestradiol-17β by Intestinal Bacteria in Rats

Abstract
In vitro experiments were carried out in which [4–14C]oestradiol-17β was incubated with a culture from caecal content from adult male rats at 37°C in an atmosphere of nitrogen. Oestrone was identified as the only certain metabolite. Other metabolites, if present, were quantitatively unimportant. The conversion of oestradiol-1to oestrone was estimated to be 22–42 %.