title: Antimicrobial substances from rhizomes of the giant knotweed Polygonum sachalinense against the fish pathogen Photobacterium damselae subsp. piscicida.
abstract: The antimicrobial compounds against the fish pathogen Photobacterium damselae subsp. piscicida were isolated from Polygonum sachalinense rhizomes. The structures of the antimicrobial compounds 1 and 2 were determined by 1H and 13C NMR, 2D-NMR (COSY, HSQC, HMBC and ROESY) and FAB-MS to be phenylpropanoid glycosides, vanicoside A and B, respectively. Both compounds have feruloyl and p-coumaroyl groups bonded to a sucrose moiety in their structures. Vanicoside A also has an acetyl group in the sucrose moiety. The MIC values for vanicoside A and B against Ph. damselae subsp. piscicida DPp-1 were 32 and 64 microg/ml, respectively. The antimicrobial activities of these vanicosides were modest, in contrast to higher activities (MICs at < 4 microg/ml) of antibiotics, florphenicol, ampicillin and amoxicillin, which have been generally used for treating pasteurellosis. The activities of the vanicosides, however, were higher than those (MICs at 256 microg/ml) of ferulic acid and p-coumaric acid. It was suggested that the structure of phenylpropanoids esterified with sucrose was essential for higher antimicrobial activity of vanicosides and also acetylation of sucrose might affect the activity against the bacterium.
authors.affiliation: Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido 041-8611, Japan.
authors.forename: Hironori
authors.initials: H
authors.lastname: Kumagai
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kawai
authors.forename: Ryo
authors.initials: R
authors.lastname: Sawano
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Kurihara
authors.forename: Koji
authors.initials: K
authors.lastname: Yamazaki
authors.forename: Norio
authors.initials: N
authors.lastname: Inoue
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002934:Cinnamates / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005393:Fish Diseases / Q000382:microbiology; D005399:Fishes / Q000382:microbiology; D007668:Kidney / Q000382:microbiology; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D010776:Photobacterium / Q000187:drug effects* / Q000302:isolation & purification; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D028502:Polygonum / Q000737:chemistry*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D027343:Rhizome / Q000737:chemistry
chemical_list: D000890:Anti-Infective Agents; D002934:Cinnamates; D010936:Plant Extracts; C087106:vanicoside B; C087105:vanicoside A; D011493:Protein Kinase C