title: Leishmanicidal and cholinesterase inhibiting activities of phenolic compounds from Allanblackia monticola and Symphonia globulifera.
abstract: In a preliminary antiprotozoal screening of several Clusiaceae species, the methanolic extracts of Allanblackia monticola and Symphonia globulifera showed high in vitro leishmanicidal activity. Further bioguided phytochemical investigation led to the isolation of four benzophenones: guttiferone A (1), garcinol (2), cambogin (3) and guttiferone F (4), along with three xanthones: allanxanthone A (5), xanthone V1 (6) and globulixanthone C (7) as active constituents. Compounds 1 and 6 were isolated from S. globulifera leaves, while compounds 2-5 were obtained from A. monticola fruits. Guttiferone A (1) and F (4) showed particulary strong leishmanicidal activity in vitro, with IC50 values (0.2 microM and 0.16 microM, respectively) comparable to that of the reference compound, miltefosine (0.46 microM). Although the leishmanicidal activity is promising, the cytotoxicity profile of these compounds prevent at this state further in vivo biological evaluation. In addition, all the isolated compounds were tested in vitro for their anticholinesterase properties. The four benzophenones showed potent anticholinesterase properties towards acetylcholinesterase (AChE) and butylcholinesterase (AChE). For AChE, the IC50 value (0.66 microM) of garcinol (2) was almost equal to that of the reference compound galanthamine (0.50 microM). Furthermore, guttiferone A (1) and guttiferone F (4) (IC50 = 2.77 and 3.50 microM, respectively) were more active than galanthamine (IC50 = 8.5) against BChE.
authors.affiliation: Department of Chemistry, Higher Teachers' Training College, University of Yaoundé 1, P.O. Box 47, Yaoundé, Cameroon. lentabruno@yahoo.fr
authors.forename: Bruno Ndjakou
authors.initials: BN
authors.lastname: Lenta
authors.forename: Catherine
authors.initials: C
authors.lastname: Vonthron-Sénécheau
authors.forename: Bernard
authors.initials: B
authors.lastname: Weniger
authors.forename: Krishna Prasad
authors.initials: KP
authors.lastname: Devkota
authors.forename: Joseph
authors.initials: J
authors.lastname: Ngoupayo
authors.forename: Marcel
authors.initials: M
authors.lastname: Kaiser
authors.forename: Qamar
authors.initials: Q
authors.lastname: Naz
authors.forename: Muhammad Iqbal
authors.initials: MI
authors.lastname: Choudhary
authors.forename: Etienne
authors.initials: E
authors.lastname: Tsamo
authors.forename: Norbert
authors.initials: N
authors.lastname: Sewald
mesh_terms: D000818:Animals; D002800:Cholinesterase Inhibitors / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D028084:Clusiaceae / Q000737:chemistry*; D007891:Leishmania / Q000187:drug effects*; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D014344:Trypanocidal Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D002800:Cholinesterase Inhibitors; D010636:Phenols; D014344:Trypanocidal Agents