Natural pentacyclic triterpenoid acids potentially useful as biocompatible nanocarriers

The importance of natural raw materials has grown recently because of their ready availability, renewable nature, biocompatibility and controllable degradability. One such group of plant-derived substances includes the triterpenoid acids, terpenic compounds consisting of six isoprene units, a carboxyl group and other functional groups producing various isomers. Most can be easily extracted from different parts of the plant and modified successfully. By themselves or as aglycones (genins) of triterpene saponins, they have potentially useful pharmaceutical activity. This review focuses on the supramolecular properties of triterpenoid acids with regard to their subsequent use as biocompatible nanocarriers. The review also considers the current list of pentacyclic triterpene acids for which molecular self-assembly has been confirmed without the need for structural modification.