title: Discovery of a new sesquiterpenoid from Phellinus ignarius with antiviral activity against influenza virus.
abstract: Seven natural products, including one new sesquiterpenoid (eudesm-1β, 6α, 11-triol, compound 1), one ergosta -4, 6, 8(14), 22-tetraen-3-one (compound 2), four polyphenols (compounds 3, 4, 5, 6), and one pyrone (3-hydroxy-2-methyl-4-pyrone, compound 7) were isolated from cultures of Phellinus ignarius by column chromatography. The detailed structure of compound 1 was determined using a combination of one- and two-dimensional nuclear magnetic resonance, mass spectrometry and infrared spectroscopy. The antiviral activity of these compounds against H5N1 influenza A virus was investigated using an MTT colorimetric assay system in Madin-Darby canine kidney cells. The results indicate that compound 1 possesses significant ability to inhibit influenza virus. The 50 % effective concentration was 0.14 ± 0.04 μM. Molecular modeling further suggested that the anti-influenza virus activity of this compound was partially attributed to the interactions of hydroxyl groups with an amino acid residue (Asn 170) of neuraminidase (NA) at the binding site. Moreover, the results of enzyme inhibition assays indicated that 50 % inhibition of NA was achieved by compound 1 at a concentration of 0.657 ± 0.325 mg/mL, which suggested that compound 1 is likely to interact with the NA enzyme.
authors.affiliation: Shandong Province Key Laboratory of Applied Mycology, School of Life Sciences, Qingdao Agricultural University, Changcheng Road 700, Chengyang, Qingdao, 266109, People's Republic of China.
authors.forename: Ai-Rong
authors.initials: AR
authors.lastname: Song
authors.forename: Xiao-Le
authors.initials: XL
authors.lastname: Sun
authors.forename: Chao
authors.initials: C
authors.lastname: Kong
authors.forename: Chen
authors.initials: C
authors.lastname: Zhao
authors.forename: Dan
authors.initials: D
authors.lastname: Qin
authors.forename: Fang
authors.initials: F
authors.lastname: Huang
authors.forename: Song
authors.initials: S
authors.lastname: Yang
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001487:Basidiomycota / Q000737:chemistry*; D002460:Cell Line; D002470:Cell Survival; D003124:Colorimetry; D004791:Enzyme Inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D053124:Influenza A Virus, H5N1 Subtype / Q000187:drug effects*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009439:Neuraminidase / Q000037:antagonists & inhibitors / Q000378:metabolism; D059808:Polyphenols / Q000302:isolation & purification / Q000494:pharmacology; D011485:Protein Binding; D011753:Pyrones / Q000302:isolation & purification / Q000494:pharmacology; D012717:Sesquiterpenes / Q000302:isolation & purification / Q000494:pharmacology*; D013055:Spectrophotometry, Infrared; D014764:Viral Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000998:Antiviral Agents; D004791:Enzyme Inhibitors; D059808:Polyphenols; D011753:Pyrones; D012717:Sesquiterpenes; D014764:Viral Proteins; C487630:NA protein, influenza A virus; D009439:Neuraminidase