title: Antiplasmodial alkaloids from the bark of Cryptocarya nigra (Lauraceae).
abstract: A dichloromethane extract of the stem bark of Cryptocarya nigra showed strong in vitro inhibition of Plasmodium falciparum growth, with an IC50 value of 2.82 μg/mL. The phytochemical study of this extract has led to the isolation and characterization of four known alkaloids: (+)-N-methylisococlaurine (1), atherosperminine (2), 2-hydroxyathersperminine (3), and noratherosperminine (4). Structural elucidation of all alkaloids was accomplished by means of high field 1D- and 2D-NMR, IR, UV and LCMS spectral data. The isolated extract constituents (+)-N-methylisococlaurine (1), atherosperminine (2) and 2-hydroxy-atherosperminine (3) showed strong antiplasmodial activity, with IC50 values of 5.40, 5.80 and 0.75 μM, respectively. In addition, (+)-N-methylisocolaurine (1) and atherosperminine (2) showed high antioxidant activity in a DPPH assay with IC50 values of 29.56 ug/mL and 54.53 ug/mL respectively. Compounds 1 and 2 also both showed high antioxidant activity in the FRAP assay, with percentages of 78.54 and 70.66 respectively and in the metal chelating assay, with IC50 values of 50.08 ug/mL and 42.87 ug/mL, respectively.
authors.affiliation: Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. ayuafiqah13@siswa.um.edu.my
authors.forename: Ayu Afiqah
authors.initials: AA
authors.lastname: Nasrullah
authors.forename: Azeana
authors.initials: A
authors.lastname: Zahari
authors.forename: Jamaludin
authors.initials: J
authors.lastname: Mohamad
authors.forename: Khalijah
authors.initials: K
authors.lastname: Awang
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000962:Antimalarials / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D031369:Cryptocarya / Q000737:chemistry; D006801:Humans; D007546:Isoquinolines / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008288:Malaria / Q000188:drug therapy / Q000469:parasitology*; D015394:Molecular Structure; D010616:Phenanthrenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D024301:Plant Bark / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D010963:Plasmodium falciparum / Q000187:drug effects*
chemical_list: C532556:2-hydroxyatherosperminine; D000470:Alkaloids; D000962:Antimalarials; D007546:Isoquinolines; D010616:Phenanthrenes; D010936:Plant Extracts; C017998:atherospermine; C004690:coclaurine