Reviewing the importance of aromatic medicinal plants in the traditional pharmacopoeia of Australian Aboriginal people

Abstract

Australia has a higher proportion of endemic aromatic species than any other continent. Many novel medicinal plants have therefore been used by the Aboriginal people, particularly including species that produce high yields of volatile compounds. Volatiles are often related to the therapeutic effects, either directly or by complementing fixed medicinal compounds and therefore acting as associated congeners guiding harvest selection. Our research has provided support for this notion, particularly with members of the genus 'Eremophila (Scrophulariaceae)'. In this regard, medicinal usage modalities often involved ritualistic smoking ceremonies (smudging), heating bundles of leaves to produce intact volatiles, such as 'Eremophila bignoniiflora', or alternatively, topical treatments using lipophilic volatile and fixed components extracted into animal fats. Additionally, species outside of Eremophila, such as Pittosporum spp. '(Pittosporaceae), Callitris' spp. '(Cypressaceae)' or 'Geijera' spp. '(Rutaceae)', were also used in a similar manner and are further explored herein. Until now, comprehensive investigation into the pharmacology, chemistry and clinical value of endemic medicinal Australian plants has mostly been restricted to a small number of species of known commercial value including 'Eucalyptus' and 'Melaleuca' species. Informed by an ethnopharmacological approach, our research extends the range of species with potential therapeutic and commercial value and provides the basis for longer term government and private investment in partnership with Aboriginal communities in an emerging health care industry addressing the imperatives of a globalized market while providing employment opportunities for Aboriginal people in marginalized regional communities.