title: Chemical characterisation of Nigerian red propolis and its biological activity against Trypanosoma Brucei.
abstract: BACKGROUND
  A previous study showed the unique character of Nigerian red propolis from Rivers State, Nigeria (RSN), with regards to chemical composition and activity against Trypanosoma brucei in comparison with other African propolis.
  
  
  OBJECTIVE
  To carry out fractionation and biological testing of Nigerian propolis in order to isolate compounds with anti-trypanosomal activity. To compare the composition of the RSN propolis with the composition of Brazilian red propolis.
  
  
  METHODS
  Profiling was carried out using HPLC-UV-ELSD and HPLC-Orbitrap-FTMS on extracts of two samples collected from RSN with data extraction using MZmine software. Isolation was carried out by normal phase and reversed phase MPLC. Elucidation of the compounds with a purity > 95% was performed by 1D/2D NMR HRMS and HRLC-MS(n) .
  
  
  RESULTS
  Ten phenolic compounds were isolated or in the case of liquiritigenin partially purified. Data for nine of these correlated with literature reports of known compounds i.e. one isoflavanone, calycosin (1); two flavanones, liquiritigenin (2) and pinocembrin (5); an isoflavan, vestitol (3); a pterocarpan, medicarpin (4); two prenylflavanones, 8-prenylnaringenin (7) and 6-prenylnaringenin (8); and two geranyl flavonoids, propolin D (9) and macarangin (10). The tenth was elucidated as a previously undescribed dihydrobenzofuran (6). The isolated compounds were tested against Trypanosoma brucei and displayed moderate to high activity. Some of the compounds tested had similar activity against wild type T. brucei and two strains displaying pentamidine resistance.
  
  
  CONCLUSIONS
  Nigerian propolis from RSN has some similarities with Brazilian red propolis. The propolis displayed anti-trypanosomal activity at a potentially useful level.
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow, G4 0NR, UK.
authors.forename: Ruwida M K
authors.initials: RM
authors.lastname: Omar
authors.affiliation: Phytochemistry Research Group, Department of Chemistry, University of Agriculture, Makurdi, Nigeria.
authors.forename: John
authors.initials: J
authors.lastname: Igoli
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow, G4 0NR, UK.
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Gray
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK.
authors.forename: Godwin Unekwuojo
authors.initials: GU
authors.lastname: Ebiloma
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow, G4 0NR, UK.
authors.forename: Carol
authors.initials: C
authors.lastname: Clements
authors.affiliation: BeeVital, Whitby, North Yorkshire, YO22 5JR, UK.
authors.forename: James
authors.initials: J
authors.lastname: Fearnley
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow, G4 0NR, UK.
authors.forename: Ru Angeli Edrada
authors.initials: RA
authors.lastname: Ebel
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow, G4 0NR, UK.
authors.forename: Tong
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK.
authors.forename: Harry P
authors.initials: HP
authors.lastname: De Koning
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow, G4 0NR, UK.
authors.forename: David G
authors.initials: DG
authors.lastname: Watson
mesh_terms: D000818:Animals; D000981:Antiprotozoal Agents / Q000737:chemistry / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D015394:Molecular Structure; D011429:Propolis / Q000737:chemistry / Q000494:pharmacology*; D013056:Spectrophotometry, Ultraviolet; D014346:Trypanosoma brucei brucei / Q000187:drug effects*
chemical_list: D000981:Antiprotozoal Agents; D011429:Propolis
keywords: Nigerian red propolis; Prenylated flavonoids; benzofuran; pentamidine resistance