Abstract
The aerial parts of alfalfa (Medicago sativa L.) contain a considerable amount of zanhic acid tridesmoside which, due to its low activity, cannot be determined using standard biological procedures. A high performance liquid chromatographic method has been developed for its determination. The procedure employs the alkaline hydrolysis of the tridesmoside followed by the derivatization of released prosapogenins with 4‐bromophenacyl bromide. It is demonstrated that alkaline hydrolysis of tridesmoside generates different prosapogenins depending on the solvent used. The conditions for alkaline hydrolysis has been optimised.