title: Antimicrobial and antioxidant activity of kaempferol rhamnoside derivatives from Bryophyllum pinnatum.
abstract: BACKGROUND
  Bryophyllum pinnatum (Lank.) Oken (Crassulaceae) is a perennial succulent herb widely used in traditional medicine to treat many ailments. Its wide range of uses in folk medicine justifies its being called "life plant" or "resurrection plant", prompting researchers' interest. We describe here the isolation and structure elucidation of antimicrobial and/or antioxidant components from the EtOAc extract of B. pinnatum.
  
  
  RESULTS
  The methanol extract displayed both antimicrobial activities with minimum inhibitory concentration (MIC) values ranging from 32 to 512 μg/ml and antioxidant property with an IC50 value of 52.48 μg/ml. Its partition enhanced the antimicrobial activity in EtOAc extract (MIC = 16-128 μg/ml) and reduced it in hexane extract (MIC = 256-1024 μg/ml). In addition, this process reduced the antioxidant activity in EtOAc and hexane extracts with IC50 values of 78.11 and 90.04 μg/ml respectively. Fractionation of EtOAc extract gave seven kaempferol rhamnosides, including; kaempferitrin (1), kaempferol 3-O-α-L-(2-acetyl)rhamnopyranoside-7-O-α-L-rhamnopyranoside (2), kaempferol 3-O-α-L-(3-acetyl)rhamnopyranoside-7-O-α-L-rhamnopyranoside (3), kaempferol 3-O-α-L-(4-acetyl)rhamnopyranoside-7-O-α-L-rhamnopyranoside (4), kaempferol 3-O-α-D- glucopyranoside-7-O-α-L-rhamnopyranoside (5), afzelin (6) and α-rhamnoisorobin (7). All these compounds, except 6 were isolated from this plant for the first time. Compound 7 was the most active, with MIC values ranging from 1 to 2 μg/ml and its antioxidant activity (IC50 = 0.71 μg/ml) was higher than that of the reference drug (IC50 = 0.96 μg/ml).
  
  
  CONCLUSIONS
  These findings demonstrate that Bryophyllum pinnatum and some of its isolated compounds have interesting antimicrobial and antioxidant properties, and therefore confirming the traditional use of B. pinnatum in the treatment of infectious and free radical damages.
authors.affiliation: Department of Chemistry, Higher Teachers' Training College, University of Maroua, P,O, Box 55, Maroua, Cameroon. jtatsimo@yahoo.com
authors.forename: Simplice Joel Ndendoung
authors.initials: SJ
authors.lastname: Tatsimo
authors.forename: Jean de Dieu
authors.initials: Jde D
authors.lastname: Tamokou
authors.forename: Léopold
authors.initials: L
authors.lastname: Havyarimana
authors.forename: Dezső
authors.initials: D
authors.lastname: Csupor
authors.forename: Peter
authors.initials: P
authors.lastname: Forgo
authors.forename: Judit
authors.initials: J
authors.lastname: Hohmann
authors.forename: Jules-Roger
authors.initials: JR
authors.lastname: Kuiate
authors.forename: Pierre
authors.initials: P
authors.lastname: Tane
mesh_terms: D000085:Acetates / Q000737:chemistry; D000890:Anti-Infective Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000235:genetics; D001713:Biphenyl Compounds / Q000037:antagonists & inhibitors / Q000737:chemistry; D002175:Candida / Q000187:drug effects / Q000254:growth & development; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D006586:Hexanes / Q000737:chemistry; D020128:Inhibitory Concentration 50; D044949:Kaempferols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D031962:Kalanchoe / Q000737:chemistry*; D000432:Methanol / Q000737:chemistry; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D010851:Picrates / Q000037:antagonists & inhibitors / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000085:Acetates; D000890:Anti-Infective Agents; D000975:Antioxidants; D001713:Biphenyl Compounds; D006027:Glycosides; D006586:Hexanes; D044949:Kaempferols; D010851:Picrates; D010936:Plant Extracts; C516876:kaempferol-7-O-alpha-L-rhamnopyranoside; C007650:ethyl acetate; C004931:1,1-diphenyl-2-picrylhydrazyl; D000432:Methanol