title: Isolation of an antimicrobial compound from Impatiens balsamina L. using bioassay-guided fractionation.
abstract: By using brine shrimp (Artemia salina) lethality test-guided fractionation, a single bioactive compound (LC(50)=26 ppm) was isolated from the 95% ethanol extract of the dried aerial parts of Impatiens balsamina L. and subsequently identified as 2-methoxy-1,4-naphthoquinone (MNQ). The structure of MNQ was confirmed by UV, FT-IR, MS, and 1-and 2-D NMR spectroscopy. The antimicrobial activity of MNQ was evaluated using 12 bacterial and eight fungal strains. Five gram-positive and two gram-negative bacteria as well as all eight fungi (including multi-drug resistant strains) tested were highly sensitive to MNQ. A tea prepared according to traditional methods was found to contain sufficient MNQ to account for its antimicrobial properties.
authors.affiliation: Department of Plant Sciences, University of Western Ontario, London, ON, Canada.
authors.forename: X
authors.initials: X
authors.lastname: Yang
authors.forename: D K
authors.initials: DK
authors.lastname: Summerhurst
authors.forename: S F
authors.initials: SF
authors.lastname: Koval
authors.forename: C
authors.initials: C
authors.lastname: Ficker
authors.forename: M L
authors.initials: ML
authors.lastname: Smith
authors.forename: M A
authors.initials: MA
authors.lastname: Bernards
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001156:Artemia / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D005658:Fungi / Q000187:drug effects*; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D029069:Impatiens; D007928:Lethal Dose 50; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D009285:Naphthoquinones / Q000737:chemistry / Q000494:pharmacology*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology; D018547:Plant Stems
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D009285:Naphthoquinones; D010936:Plant Extracts; C096118:2-methoxy-1,4-naphthoquinone