Isolation of Flavonoids and Triterpenoids from the Fruits of Alphitonia Neocaledonica and Evaluation of their Anti-oxidant, Anti- tyrosinase and Cytotoxic Activities Dima Muhammad, a Jane Hubert, a Nathalie Lalun, b Jean-Hugues Renault, a Hélène Bobichon, b Mohammed Nour c and Laurence Voutquenne-Nazabadioko a * ABSTRACT: Introduction – Alphitonia neocaledonica (Rhamnaceae) is an endemic tree of New Caledonia. Although three flavonoids have been identified in the leaves, the secondary metabolite profile of the fruits has never been investigated. Objective – Phytochemical investigation of A. neocaledonica fruits and evaluation of their anti-oxidant, anti-tyrosinase and cytotoxic activities. Methods – A hydromethanolic extract was fractionated by liquid–liquid extraction to obtain ethyl acetate and n-butanolic fractions. The ethyl-acetate-soluble part was purified by silica-gel column chromatography and high-performance liquid chro- matography (HPLC). The n-butanol-soluble part was fractionated by centrifugal partition extraction (CPE) and the collected fractions were further purified by centrifugal partition chromatography (CPC) and HPLC. The chemical structures of the puri- fied compounds were identified by nuclear magnetic resonance and mass spectrometry. Results – Three triterpenoids and one flavonoid were isolated from the ethyl-acetate-soluble part. Fractions enriched in triterpenoids, flavonoids and catechin derivatives were obtained from the n-butanol-soluble part. Gallocatechin and flavo- noids were obtained as pure compounds by further CPC and HPLC purification. The n-butanolic-soluble part showed anti- oxidant and anti-tyrosinase activities due to the presence of tannins and gallocatechin. The triterpenoid alphitolic acid showed a moderate cytotoxic activity against KB cell line (median inhibition concentration = 8.5 μM). Conclusions – Nine known compounds including three triterpenes, five flavonoids and (+) gallocatechin, as well as a new 3-O- (6-E-feruloyl)-β-D-glucopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 2)-]α-L-rhamnopyranosyl-quercetin, were isolated from A. neocaledonia fruits. The hydromethanolic extract possesses a potential cytotoxic activity due to the presence of triterpenes, and it can also be valuable as a cosmetic ingredient for its anti-oxidant and anti-tyrosinase activities. Copyright © 2014 John Wiley & Sons, Ltd. Supporting information can be found in the online version of this article Keywords: Centrifugal partition extraction; Centrifugal partition chromatography; three-phase solvent system; triterpenoids; flavonoids; fruits; Alphitonia neocaledonica Introduction New Caledonia is well known for its high biodiversity, with a to- tal endemic area of 74.3%. This high endemicity is partly due to the multiplicity of geological substrates, with one-third of the to- tal area covered by ultramafic rocks. Erosion and alteration of these rocks have led to nutrient depletion and soil enrichment with heavy metals, resulting in the development of a unique flora. Alphitonia neocaledonica (Schltr.) Guillaumin (Rhamnaceae) is an endemic small forest tree of New Caledonia growing on this ultramafic soil rich in extractable nickel. This tree is found throughout the mainland, the Isle of Pines (Southern Province), Bélep and Yandé (Northern Province). The fruits are black, round, about the size of a small cherry, not edible, and contain two to three very hard nuclei with shiny, black and very hard seeds (Suprin, 1992). The fresh bark, bitter and astringent, exudes a clear balsamic odour of methyl salicylate and is traditionally used to treat skin diseases (eczema, ecthyma, pityriasis) and rheumatic pains (Suprin, 1992). The leaves are used locally to fa- cilitate childbirth (Suprin, 1992). The fatty acids profile of the * Correspondence to: L. Voutquenne-Nazabadioko, UMR CNRS 7312, Université de Reims, Champagne-Ardenne, Bât. 18, Moulin de la Housse, BP 1039 51687 Reims, Cedex 2, France. Email: laurence.nazabadioko@univ-reims.fr a UMR CNRS 7312, Université de Reims Champagne-Ardenne, Bât. 18, Moulin de la Housse, BP 1039, 51687 Reims, Cedex 2, France b CNRS FRE 3481, Université de Reims Champagne Ardenne, 51 rue cognacq- Jay, 51095 Reims cedex, France c Laboratoire Insulaire du Vivant et de l’Environnement (LIVE), EA 4243, Université de la Nouvelle-Calédonie, BP R4, 98851 Nouméa Cedex, Nouvelle-Calédonie Phytochem. Anal. 2014 Copyright © 2014 John Wiley & Sons, Ltd. Research Article Received: 18 April 2014, Revised: 5 September 2014, Accepted: 12 September 2014 Published online in Wiley Online Library (wileyonlinelibrary.com) DOI 10.1002/pca.2545