title: Emodin is identified as the active component of ether extracts from Rhizoma Polygoni Cuspidati, for anti-MRSA activity.
abstract: This study investigated the anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity and chemical compositions of ether extracts from Rhizoma Polygoni Cuspidati (ET-RPC). Significant anti-MRSA activities of ET-RPC against MRSA252 and MRSA clinical strains were tested in in vitro antibacterial experiments, such as inhibition zone diameter test, minimal inhibitory concentration test, and dynamic bacterial growth assay. Subsequently, 7 major compounds of ET-RPC were purified and identified as polydatin, resveratrol-4-O-d-(6'-galloyl)-glucopyranoside, resveratrol, torachryson-8-O-glucoside, emodin-8-O-glucoside, 6-hydroxy-emodin, and emodin using liquid chromatography - electrospray ionization - tandem mass spectrometry. After investigation of anti-MRSA activities of the 7 major compounds, only emodin had significant anti-MRSA activity. Further, transmission electron microscopy was used to observe morphological changes in the cell wall of MRSA252, and the result revealed that emodin could damage the integrity of cell wall, leading to loss of intracellular components. In summary, our results showed ET-RPC could significantly inhibit bacterial growth of MRSA strains. Emodin was identified as the major compound with anti-MRSA activity; this activity was related to destruction of the integrity of the cell wall and cell membrane.
authors.affiliation: Department of Pharmacology, College of Pharmacy, the Third Military Medical University, Gaotanyan Street 30, Shapingba District, Chongqing 400038, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Cao
authors.forename: Wei
authors.initials: W
authors.lastname: Peng
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Li
authors.forename: Ming
authors.initials: M
authors.lastname: Liu
authors.forename: Bin
authors.initials: B
authors.lastname: Li
authors.forename: Rongxin
authors.initials: R
authors.lastname: Qin
authors.forename: Weiwei
authors.initials: W
authors.lastname: Jiang
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Cen
authors.forename: Xichun
authors.initials: X
authors.lastname: Pan
authors.forename: Zifei
authors.initials: Z
authors.lastname: Yan
authors.forename: Kangkang
authors.initials: K
authors.lastname: Xiao
authors.forename: Hong
authors.initials: H
authors.lastname: Zhou
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects; D002473:Cell Wall / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000494:pharmacology; D004642:Emodin / Q000737:chemistry* / Q000494:pharmacology*; D005960:Glucosides / Q000737:chemistry / Q000494:pharmacology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D000077185:Resveratrol; D027343:Rhizome / Q000737:chemistry*; D013267:Stilbenes / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D004365:Drugs, Chinese Herbal; D005960:Glucosides; D013267:Stilbenes; D004642:Emodin; D000077185:Resveratrol; C058229:polydatin
keywords: MRSA; Polygonum cuspidatum; SARM; activité anti-SARM; anti-MRSA activity; cell wall; emodin; ether extracts; extraits à l’éther; paroi cellulaire; émodine