In Vitro Metabolic Stability and Intestinal Transport of P57AS3 (P57) from Hoodia gordonii and its Interaction with Drug Metabolizing Enzymes - Madgula, Vamsi L.M.; Avula, Bharathi; Pawar, Rahul S.; Shukla, Yatin J.; Khan, Ikhlas A.; Walker, Larry A.; Khan, Shabana I. (Planta Medica, 2008)