title: Phytochemical composition, antiparasitic and α-glucosidase inhibition activities fromPelliciera rhizophorae.
abstract: BACKGROUND
  Panama has an extensive mangrove area and it is one of the countries with the highest biodiversity in America. Mangroves are widely used in traditional medicine, nevertheless, there are very few studies that validates their medicinal properties in America. Given the urgent need for therapeutic options to treat several diseases of public health importance, mangrove ecosystem could be an interesting source of new bioactive molecules. This study was designed to evaluate the potential ofPelliciera rhizophoraeas a source of bioactive compounds.
  
  
  RESULTS
  The present investigation was undertaken to explore the possible antiparasitic potential and α-glucosidase inhibition by compounds derived from the Panamanian mangrovePelliciera rhizophorae. Bioassay-guided fractionation of the crude extract led to the isolation of ten chemical compounds: α-amyrine (1), β-amyrine (2), ursolic acid (3), oleanolic acid (4), betulinic acid (5), brugierol (6) iso-brugierol (7), kaempferol (8), quercetin (9), and quercetrin (10). The structures of these compounds were established by spectroscopic analyses including APCI-HR-MS and NMR. Compounds4(IC50= 5.3 µM),8(IC50= 22.9 µM) and10(IC50= 3.4 µM) showed selective antiparasitic activity againstLeishmania donovani, while compounds1(IC50= 19.0 µM) and5(IC50= 18.0 µM) exhibited selectivity againstTripanosoma cruziandPlasmodium falciparum, respectively. Moreover, compounds1-5inhibited α-glucosidase enzyme in a concentration-dependent manner with IC50values of 1.45, 0.02, 1.08, 0.98 and 2.37 µM, respectively. Their inhibitory activity was higher than that of antidiabetic drug acarbose (IC50217.7 µM), used as a positive control. Kinetic analysis established that the five compounds acted as competitive inhibitors. Docking analysis predicted that all triterpenes bind at the same site that acarbose in the human intestinal α-glucosidase (PDB: 3TOP).
  
  
  CONCLUSIONS
  Three groups of compounds were isolated in this study (triterpenes, flavonols and dithiolanes). Triterpenes and flavones showed activity in at least one bioassay (antiparasitic or α-glucosidase). In addition, only the pentacyclic triterpenes exhibited a competitive type of inhibition against α-glucosidase.
authors.affiliation: Center for Drug Discovery and Biodiversity, Institute for Scientific Research and Technology Services (INDICASAT), Clayton, P.O. Box 0843-01103, Panama City, Republic of Panama ; Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur, 522510 India.
authors.forename: Dioxelis
authors.initials: D
authors.lastname: López
authors.affiliation: Department of Organic Chemistry, Chemistry School, Faculty of Natural Sciences, Exact and Technology, University of Panama, P.O. Box 3366, Panama City, Republic of Panama.
authors.forename: Lilia
authors.initials: L
authors.lastname: Cherigo
authors.affiliation: Center for Cellular and Molecular Biology of Diseases, Institute for Scientific Research and Technology Services (INDICASAT), Clayton, P.O. Box 0843-01103, Panama City, Republic of Panama.
authors.forename: Carmenza
authors.initials: C
authors.lastname: Spadafora
authors.affiliation: Facultad de Ciencias Químicas, Universidad La Salle, Benjamín Franklin 47, Cuauhtémoc, 06140 Mexico City, Mexico.
authors.forename: Marco A
authors.initials: MA
authors.lastname: Loza-Mejía
authors.affiliation: Center for Drug Discovery and Biodiversity, Institute for Scientific Research and Technology Services (INDICASAT), Clayton, P.O. Box 0843-01103, Panama City, Republic of Panama.
authors.forename: Sergio
authors.initials: S
authors.lastname: Martínez-Luis
keywords: Diabetes; Mangroves; Pelliciera rhizophorae; Triterpenes; α-Glucosidase