Anti-mycobacterial natural products from Aralia nudicaulis

H Li; T O'Neill; K Ellsworth; D Webster; JA Johnson; CA Gray

doi:10.1055/s-0032-1320584

Planta Medica, Inhaltsverzeichnis

Anti-mycobacterial natural products from Aralia nudicaulis

H Li ¹, T O'Neill ¹, K Ellsworth ¹, D Webster ², JA Johnson ¹, CA Gray ¹^,³

¹Department of Biology, University of New Brunswick, Saint John, NB E2L4L5, Canada
²Division of Infectious Diseases, Saint John Regional Hospital, Saint John, NB E2L4L2, Canada
³Department of Chemistry, University of New Brunswick, Saint John, NB E2L4L5, Canada

Abstract

Infusions of the rhizomes of Aralia nudicaulis (wild sarsaparilla) are widely used as a traditional medicine to treat respiratory ailments by various First Nation communities in Canada. Methanolic extracts of A. nudicaulis rhizomes were found to have significant antimycobacterial activity when screened in the microplate resazurin assay against Mycobacterium tuberculosis (H37Ra). Bioassay guided fractionation of the rhizome extract resulted in the isolation of two C17 diynes identified as falcarinol and panaxydol by NMR and MS that exhibited MICs of 25.6µM and 36.0µM and IC₅₀s of 15.3µM and 23.5µM against M. tuberculosis (H37Ra), respectively. Additionally, seven endophytic fungi were isolated from the leaves of A. nudicaulis, and extracts of two of these have also exhibited significant anti-mycobacterial activity. The endophyte extracts will be screened using LC-MS to investigate whether falcarinol and panaxydol could be responsible for the anti-mycobacterial activity of both plant and endophyte extracts.