title: A bioactivity-guided study on the anti-diarrheal activity of Polygonum chinense Linn.
abstract: BACKGROUND
  Polygonum chinense Linn., a folk medicine, has long been used for the treatment of diarrhea and enteritis in southwestern China. However, the components responsible for its anti-diarrheal activity are still poorly understood.
  
  
  OBJECTIVE
  To determine anti-diarrheal activities of Polygonum chinense L. and to identify its active components through bioactivity-guided isolation technique.
  
  
  METHODS
  Animals were orally administered with the extract of Polygonum chinense L. The anti-diarrheal effects of 75% ethanol extract, four fractions with different polarities from 75% ethanol extract, different eluates collected from Diaion HP-20 macroporous resin chromatography, ellagic acid and corilagin, were examined based on mouse models of castor oil- and magnesium sulfate-induced diarrhea.
  
  
  RESULTS
  The results showed that the 75% ethanol extract of Polygonum chinense L. exhibited significant anti-diarrheal activities in a dose-dependent manner in two mouse models. Through in vivo bioactivity-guided fractionation processes, n-butanol and aqueous fractions were found to exhibit prominent anti-diarrheal activities, and two major compounds, ellagic acid and corilagin, from these active fractions were found to possess anti-diarrheal effects.
  
  
  CONCLUSIONS
  Present study provides evidence of the utilization of Polygonum chinense L. for diarrhea, and ellagic acid and corilagin are two components contributing to the anti-diarrheal effect.
authors.affiliation: School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR.
authors.forename: Hai-Tao
authors.initials: HT
authors.lastname: Xiao
authors.forename: Siu-Wai
authors.initials: SW
authors.lastname: Tsang
authors.forename: Hong-Yan
authors.initials: HY
authors.lastname: Qin
authors.forename: Franky F K
authors.initials: FF
authors.lastname: Choi
authors.forename: Zhi-Jun
authors.initials: ZJ
authors.lastname: Yang
authors.forename: Quan-Bin
authors.initials: QB
authors.lastname: Han
authors.forename: Hu-Biao
authors.initials: HB
authors.lastname: Chen
authors.forename: Hong-Xi
authors.initials: HX
authors.lastname: Xu
authors.forename: Hong
authors.initials: H
authors.lastname: Shen
authors.forename: Ai-Ping
authors.initials: AP
authors.lastname: Lu
authors.forename: Zhao-Xiang
authors.initials: ZX
authors.lastname: Bian
mesh_terms: D000818:Animals; D000930:Antidiarrheals / Q000627:therapeutic use*; D002368:Castor Oil; D005591:Chemical Fractionation; D003967:Diarrhea / Q000188:drug therapy*; D004610:Ellagic Acid / Q000627:therapeutic use*; D005960:Glucosides / Q000627:therapeutic use*; D047348:Hydrolyzable Tannins; D008278:Magnesium Sulfate; D051379:Mice; D008813:Mice, Inbred ICR; D008517:Phytotherapy; D035261:Plant Components, Aerial; D010936:Plant Extracts / Q000627:therapeutic use*; D028502:Polygonum; D012997:Solvents / Q000737:chemistry
chemical_list: D000930:Antidiarrheals; D005960:Glucosides; D047348:Hydrolyzable Tannins; D010936:Plant Extracts; D012997:Solvents; D004610:Ellagic Acid; C049096:corilagin; D008278:Magnesium Sulfate; D002368:Castor Oil
keywords: 25%/50%/95% ethanol subfraction; AF; ASF; Anti-diarrheal activity; BF; CMC-Na; Corilagin; EE; EF; ESF25/50/95; Ellagic acid; HPLC; LC-UV-MS-MS; MDI; MSR; PF; Polygonum chinense Linn.; TLC; UHPLC; UV; aqueous fraction; aqueous subfraction; ethanol extract; ethyl acetate fraction; high-performance liquid chromatography; liquid chromatography-ultraviolet-tandem mass spectrometry; maximum absorption wavelength; mean diarrheal index; mean stool grade; mean stool rate; n-butanol fraction; petroleum ether fraction; retention time; sodium carboxymethylcellulose; t(R); thin layer chromatography; ultra high-performance liquid chromatography; ultraviolet; λ(max)