New lignan glycosides from Justicia secunda Vahl (Acanthaceae) with antimicrobial and antiparasitic properties
Viviane Flore Kamlo Kamso,
Yanick Kevin Dongmo Melogmo,
Billy Toussie Tchegnitegni,
Mariscal Brice Tchatat Tali,
Darline Dize,
Cyrille Njampa Ngansop,
Pantaléon Ambassa,
Judith Laure Ouete Nantchouang,
Ingrid Simo Konga,
Fabrice Fekam Boyom,
Bonaventure Tchaleu Ngadjui,
Ghislain Wabo Fotso
Affiliations
Viviane Flore Kamlo Kamso
Department of Organic Chemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
Yanick Kevin Dongmo Melogmo
Department of Biochemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
Billy Toussie Tchegnitegni
Department of Chemistry, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon
Mariscal Brice Tchatat Tali
Department of Biochemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
Darline Dize
Department of Biochemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
Cyrille Njampa Ngansop
Department of Biochemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
Pantaléon Ambassa
Department of Organic Chemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
Judith Laure Ouete Nantchouang
Department of Organic Chemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
Ingrid Simo Konga
Department of Chemistry, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon
Fabrice Fekam Boyom
Department of Biochemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
Bonaventure Tchaleu Ngadjui
Department of Organic Chemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon; University Institute of Sciences, Technologies and Ethics, P.O. Box 30201, Yaoundé, Cameroon
Ghislain Wabo Fotso
Department of Organic Chemistry, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon; Corresponding author.
Three new lignan glucosides, namely, justisecundosides A (1), B (2a), and C (2b), were isolated from the whole plant of Justicia secunda together with seven known compounds (3−9). Their structures were established based on a comprehensive analysis of HR-ESI-MS, IR, UV, and CD, in conjunction with their 1D and 2D-NMR data. A putative biogenetic pathway of compounds 1−2a,b from coniferyl alcohol was proposed. In addition, the antimicrobialactivities of the extract, fractions, and some isolated compounds were assessed against multiresistant bacterial and fungal strains. Furthermore, the antiplasmodial, antileishmanial, and antitrypanosomal activities were assessed against the sensitive (3D7) and multidrug-resistant (Dd2) strains of P. falciparum, promastigote and bloodstream forms of L. donovani, and Trypanosoma brucei, respectively. Compound 4 exhibited moderate antibacterial activity against Staphylococcus aureus SA RN 46003 with a MIC value of 62.5 μg/mL. Besides, compound 6 demonstrated a very good activity against sensitive (IC50 Pf3D7: 0.81 μg/mL) and multidrug-resistant (IC50 PfDd2: 14.61 μg/mL) strains of P. falciparum while compound 4 displayed good antitrypanosomal activity (IC50: 1.19 μg/mL). Also, compound 1 was the most active on the promastigote form of L. donovani with an IC50 of 13.02 μg/mL.
