Formation of nitrogen-containing metabolites from the main iridoids of Harpagophytum procumbens and H-zeyheri by human intestinal bacteria

The study of the metabolism of iridoid glycosides from Harpagophytum procumbens and Harpogophylum zeyheri by human intestinal bacteria, was realized in order to elucidate compounds responsible for the pharmacological activities of Harpagophytum. Harpagide, harpagoside and 8-O-p-coumaroylharpagide were transformed into the pyridine monoterpene alkaloid aucubinine B by human fecal flora and by bacteria isolated from this flora, Aucubinine B was also prepared from harpagide, harpagoside and 8-O-p-coumaroylharpagide, by beta-glucosidase in the presence of NH4+.