Gardenine is a metabolite produced from Gardenoside (HY-N1478) by K. pneumonia[1].
References
[1] Kawata Y, et al. Formation of nitrogen-containing metabolites from geniposide and gardenoside by human intestinal bacteria. Planta Med. 1991 Dec;57(6):536-42. DOI:10.1055/s-2006-960201