Bioguided Fractionation and Isolation of an Antiplasmodial Saponin from the Roots of Nauclea xanthoxylon (A.Chev.) Aubrév. (Rubiaceae). Issue 4 (22nd March 2023)

• Record Type: Journal Article
• Authors: Nkouayeb Nangmou, Brice Maxime; Maza Djomkam, Hermine Laure; Bellier Tabekoueng, Georges; Tékapi Tsopgni, Willifred Dongmo; Mbahbou Bitchagno, Gabin Thierry; Mbock, Michel Arnaud; Kamkumo, Raceline Gounoue; Frese, Marcel; Ndjakou Lenta, Bruno; Ngouela, Silvère Augustin; Sewald, Nobert; Blaise Azebaze, Anatole Guy
• Is Part Of: Chemistry & biodiversity. Volume 20:Issue 4(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-03-22
• Subjects: Nauclea xanthoxylon -- Plasmodium falciparum -- saponin -- xanthoxyloside; Biochemistry -- Periodicals; Molecular biology -- Periodicals; Biodiversity -- Periodicals; 572
• DOI: 10.1002/cbdv.202200271
• Languages: English
• ISSNs: 1612-1872

Abstract

Abstract: The root extract of Nauclea xanthoxylon (A.Chev.) Aubrév. displayed significant 50 % inhibition concentration (IC50 s) of 0.57 and 1.26 μg/mL against chloroquine resistant and sensitive Plasmodium falciparum ( Pf ) Dd2 and 3D7 strains, respectively. Bio‐guided fractionation led to an ethyl acetate fraction with IC50 s of 2.68 and 1.85 μg/mL and subsequently, to the new quinovic acid saponin named xanthoxyloside (1 ) with IC50 s of 0.33 and 1.30 μM, respectively against the tested strains. Further compounds obtained from ethyl acetate and hexane fractions were the known clethric acid (2 ), ursolic acid (3 ), quafrinoic acid (4 ), quinovic acid (5 ), quinovic acid 3‐ O ‐ β ‐D‐fucopyranoside (6 ), oleanolic acid (7 ), oleanolic acid 3‐acetate (8 ), friedelin (9 ), β‐sitosterol (10a ), stigmasterol (10b ) and stigmasterol 3‐ O‐β‐ D‐glucopyranoside (11 ). Their structures were characterised with the aid of comprehensive spectroscopic methods (1 and 2D NMR, Mass). Bio‐assays were performed using nucleic acid gel stain (SYBR green I)‐based fluorescence assay with chloroquine as reference. Extracts and compounds exhibited good selectivity indices (SIs) of >10. Significant antiplasmodial activities measured for the crude extract, the ethyl acetate fraction and xanthoxyloside (1 ) from that fraction can justify the use of the root of N. xanthoxylon in ethnomedicine to treat malaria. Abstract :