Extraction of Bioactive Sesquiterpene Lactones from Magnolia grandiflora Using Supercritical Carbon Dioxide and Near-Critical Propane

Abstract

The bioactive sesquiterpene lactones parthenolide and costunolide, as well as the tricyclic sesquiterpene cyclocolorenone, were extracted from the leaves of Magnolia grandiflora by supercritical extraction with carbon dioxide and by near-critical extraction with propane. Parthenolide, costunolide, and cyclocolorenone in the extracts were identified by 1 H NMR and quantified by HPLC. Results indicate that supercritical carbon dioxide selectively removed parthenolide, costunolide, and cyclocolorenone when compared to standard liquid dichloromethane or near-critical propane extraction. HPLC traces show that the carbon dioxide extract is virtually clean of any chlorophyll or fatty material peaks which hinder isolation of these chemicals