Phenanthrenes from Juncus inflexus with Antimicrobial Activity against Methicillin-Resistant Staphylococcus aureus.
The present study has focused on an investigation of the antibacterial effects of Juncus inflexus and the isolation and identification of its active compounds. Eleven phenanthrenes were isolated from a methanolic extract of the roots. Four compounds (jinflexins A-D, 1-4) are new natural products, while seven phenanthrenes [juncuenins A (5), B (6), and D (8), juncusol (7), dehydrojuncuenins A (9) and B (11), and dehydrojuncusol (10)] were isolated for the first time from the plant. Jinflexin D (4) is a dimer with an unprecedented heptacyclic ring system. The absolute configurations of the new compounds were determined by TDDFT-ECD calculations, and their enantiomeric purity was checked by chiral HPLC analysis. Extracts of different polarity (n-hexane, dichloromethane, and ethyl acetate) were evaluated for their antimicrobial effects against methicillin-resistant Staphylococcus aureus, extended-spectrum β-lactamase (ESBL)-producing Citrobacter freundii, Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, multiresistant Acinetobacter baumannii, and Pseudomonas aeruginosa. The MIC values of the isolated compounds were determined by a microdilution method. Jinflexin B (2), juncusol (7), juncuenin D (8), and dehydrojuncuenin B (11) showed significant activity (MIC value range 12.5-100 μg/mL) against MRSA strains.
Barbara
B
Tóth
Erika
E
Liktor-Busa
Norbert
N
Kúsz
Department of Organic Chemistry, University of Debrecen , 4032 Debrecen, Hungary.
Ádám
Á
Szappanos
Department of Organic Chemistry, University of Debrecen , 4032 Debrecen, Hungary.
Attila
A
Mándi
Department of Organic Chemistry, University of Debrecen , 4032 Debrecen, Hungary.
Tibor
T
Kurtán
Institute of Clinical Microbiology, University of Szeged , 6725 Szeged, Hungary.
Edit
E
Urbán
Judit
J
Hohmann
Department of Marine Biotechnology and Resources, National Sun Yat-sen University , 804 Kaohsiung, Taiwan.
Fang-Rong
FR
Chang
Andrea
A
Vasas
D040981:Acinetobacter baumannii / Q000187:drug effects; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects; D006586:Hexanes / Q000737:chemistry; D006814:Hungary; D007711:Klebsiella pneumoniae / Q000187:drug effects; D019684:Magnoliopsida / Q000737:chemistry*; D008712:Methicillin / Q000494:pharmacology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010616:Phenanthrenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D001618:beta-Lactamases / Q000378:metabolism
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D006586:Hexanes; D010616:Phenanthrenes; C026385:n-hexane; C014063:juncusol; D001618:beta-Lactamases; D008712:Methicillin