title: Bioactivity-guided isolation of the active compounds from Rosa nutkana and quantitative analysis of ascorbic acid by HPLC.
abstract: Rosa nutkana Presl. (Rosaceae) is distributed abundantly throughout central and southern areas of British Columbia, Canada. Aboriginal people in the Pacific Northwest have traditionally used R. nutkana as a food, medicine, and source of cultural material. The methanolic extract of the fruits of R. nutkana was previously found to have inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA). In our study, bioactivity-guided fractionation of the methanol extract from R. nutkana led to the isolation of the following 10 compounds: (i) tormentic acid, (ii) euscaphic acid, (iii) ursolic acid, (iv) maslinic acid, (v) quercetin, (vi) catechin gallate, (vii) quercetin-3-O-glucoside, (viii) 1,2,3,4,6-penta-O-galloyl-beta-D-glucoside, (ix) L-ascorbic acid (vitamin C), and (x) 1,6-digalloyl-beta-D-glucoside. Structures were elucidated by ultraviolet, infrared, mass spectrometry, and nuclear magnetic resonance data, as well as by comparison with those of the literature. The compounds quercetin, catechin gallate, quercetin-3-O-glucoside, 1,2,3,4,6-penta-O-galloyl-beta-D-glucoside, and 1,6-digalloyl-beta-D-glucoside exhibited weak antibacterial activity against MRSA. Our research demonstrates the value of traditional knowledge held by Aboriginal people in the Pacific Northwest with respect to uses of R. nutkana. Some described uses in the ethnobotanical literature correspond to activities observed under laboratory conditions. Further work on British Columbia Rosa spp. may contribute to identifying other potential therapeutic uses.
authors: Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada. eduardoJ@interchange.ubc.ca
authors: Eduardo M
authors: EM
authors: Jovel
authors: Xi Ling
authors: XL
authors: Zhou
authors: Dong Sheng
authors: DS
authors: Ming
authors: Tanya R
authors: TR
authors: Wahbe
authors: G H Neil
authors: GH
authors: Towers
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis / Q000737:chemistry; D001205:Ascorbic Acid / Q000032:analysis / Q000494:pharmacology; D002392:Catechin / Q000031:analogs & derivatives / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D005638:Fruit / Q000737:chemistry; D005960:Glucosides / Q000032:analysis / Q000494:pharmacology; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D011794:Quercetin / Q000032:analysis; D027826:Rosa; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D005960:Glucosides; D010936:Plant Extracts; C417939:catechin gallate; D002392:Catechin; D011794:Quercetin; D001205:Ascorbic Acid