12th Pacific Science Inter-Congress, 8-12 July 2013
University of the South Pacific, Laucala Bay Campus, Suva, Fiji
STUDY OF A MARQUESAN TRADITIONAL MEDICINAL PLANT: R.
NUKUHIVENSIS
Nicolas J. Martin1 , Olivier P. Thomas2, Gael Lecellier1, Carmela Lopes1, Mael Nicolas1, Soizic Prado3,
Christian Paetz4 and Phila Raharivelomanana1
1
EIMS Laboratory UMR 241 EIO, University of French Polynesia, 98702 Faa'a, Tahiti, French
Polynesia; E-Mail: [email protected], [email protected], [email protected],
[email protected], [email protected]
2
ICN UMR 7272, University of Nice Sophia-Antipolis, Parc Valrose 06108 Nice Cedex 2, France, EMail:[email protected]
3
MNHN UMR CMAM 7245, 63 rue Buffon, 75230 Paris, France E-Mail:[email protected]
4
MPI for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany, E-Mail:[email protected]
Rauvolfia nukuhivensis (Apocynaceae) is an endemic species grown in Marquesas
archipelago where it is used as a traditional medicine. The frequent use of its bark
(macerate) and climatic conditions contributed to its rarefaction and so, the plant is now
classified as an endangered species (“Critical Rare” UICN status). Data regarding specific
taxonomy and the pharmacological principles were not available until now. We developped
two approaches on these topics: the taxonomy based on DNA barcoding using the rps16
locus which is found to be a good discriminant of Rauvolfia genus and phytochemical
investigations. DNA barcoding was used to assess genetic characterization of Rauvolfia
species from the Pacific region like Rauvolfia semperflorens var. semperflorens from New
Caledonia and Rauvolfia sandwicensis from Hawaii. The phytochemical investigation of the
raw plant extract, but also of the traditional preparation associated to this popular
medicinal plant, resulted in the isolation and identification of several alkaloids belonging to
the ajmaline type including new chemical structures. Ajmaline derivatives are well known in
the Rauvolfia species like in Rauvolfia sandwicensis. Bioassays were carried out in order to
assess the efficency of the remedy against human pathogens. Antibacterial and antifungal
activities against Staphylococcus aureus, Escherichia coli, Aspergillus niger and Candida
albicans were tested and moderate antifungal activities were observed for some alkaloids.
Key Words: Rauvolfia, alkaloids, genetic discrimination