Fractionation Coupled to Molecular Networking: Towards Identification of Anthelmintic Molecules in <i>Terminalia leiocarpa</i> (DC.) Baill
Esaïe Tchetan,
Sergio Ortiz,
Pascal Abiodoun Olounladé,
Kristelle Hughes,
Patrick Laurent,
Erick Virgile Bertrand Azando,
Sylvie Mawule Hounzangbe-Adote,
Fernand Ahokanou Gbaguidi,
Joëlle Quetin-Leclercq
Affiliations
Esaïe Tchetan
Laboratoire d’Ethnopharmacologie et de Santé Animale, Faculté des Sciences Agronomiques, Université d’Abomey-Calavi, Cotonou 01 BP 526, Benin
Sergio Ortiz
Pharmacognosy Research Group, Louvain Drug Research Institute, Université Catholique de Louvain (UCLouvain), Avenue E. Mounier, 72, B1.72.03, B-1200 Brussels, Belgium
Pascal Abiodoun Olounladé
Unité de Recherche en Zootechnie et Système d’Elevage (EGESE), Laboratoire des Sciences Animale et Halieutique (LaSAH), Ecole de Gestion et d’Exploitation des Sytèmes d’Elevage (EGESE), Université Nationale d’Agriculture (UNA), Porto-Novo 01 BP 55, Benin
Kristelle Hughes
Pharmacognosy Research Group, Louvain Drug Research Institute, Université Catholique de Louvain (UCLouvain), Avenue E. Mounier, 72, B1.72.03, B-1200 Brussels, Belgium
Patrick Laurent
Laboratory of Neurophysiology, ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), 808 route de Lennik, CP601, 1070 Brussels, Belgium
Erick Virgile Bertrand Azando
Laboratoire d’Ethnopharmacologie et de Santé Animale, Faculté des Sciences Agronomiques, Université d’Abomey-Calavi, Cotonou 01 BP 526, Benin
Sylvie Mawule Hounzangbe-Adote
Laboratoire d’Ethnopharmacologie et de Santé Animale, Faculté des Sciences Agronomiques, Université d’Abomey-Calavi, Cotonou 01 BP 526, Benin
Fernand Ahokanou Gbaguidi
Laboratoire de Chimie Organique et Chimie Pharmaceutique, UFR Pharmacie, Faculté des Sciences de la Santé, Université d’Abomey-Calavi, Cotonou 01 BP 188, Benin
Joëlle Quetin-Leclercq
Pharmacognosy Research Group, Louvain Drug Research Institute, Université Catholique de Louvain (UCLouvain), Avenue E. Mounier, 72, B1.72.03, B-1200 Brussels, Belgium
Terminalia leiocarpa is a medicinal plant widely used in ethnoveterinary medicine to treat digestive parasitosis whose extracts were shown to be active against gastrointestinal nematodes of domestic ruminants. The objective of our study was to identify compounds responsible for this activity. Column fractionation was performed, and the activity of the fractions was assessed in vitro on Haemonchus contortus and Caenorhabditis elegans as well as their cytotoxicity on WI38 fibroblasts. Two fractions were the most active on both nematode models and less cytotoxic. LC-MS/MS analysis and manual dereplication coupled to molecular networking allowed identification of the main compounds: ellagic acid and derivatives, gallic acid, astragalin, rutin, quinic acid, and fructose. Other potentially identified compounds such as shikimic acid, 2,3-(S)-hexahydroxydiphenoyl-D-glucose or an isomer, quercetin-3-O-(6-O-galloyl)-β-D-galactopyranoside or an isomer, and a trihydroxylated triterpenoid bearing a sugar as rosamultin are reported in this plant for the first time. Evaluation of the anthelmintic activity of the available major compounds showed that ellagic and gallic acids were the most effective in inhibiting the viability of C. elegans. Their quantification in fractions 8 and 9 indicated the presence of about 8.6 and 7.1 µg/mg ellagic acid and about 9.6 and 2.0 µg/mg gallic acid respectively. These concentrations are not sufficient to justify the activity observed. Ellagic acid derivatives and other compounds that were found to be positively correlated with the anthelmintic activity of the fractions may have additive or synergistic effects when combined, but other unidentified compounds could also be implicated in the observed activity.
