title: [Study on the optimal harvesting time of Rumex gmelini by analyzing the contents of principal components].
abstract: OBJECTIVE
  To establish a method used for optimization of harvesting time and determine the best time for harvesting Rumex gmelini.
  
  
  METHODS
  An HPLC method was applied to determinate the contents of seven active constituents(resveratrol, polydatin, chrysophanol 1-glucoside, nepodin, emodin, chrysophanol and physcion)of R. gmelini at different development stage. The result was analyzed by principal component analysis.
  
  
  RESULTS
  The accumulation of active constituents showed a regular pattern.
  
  
  CONCLUSIONS
  The best harvesting time of R. gmelini is early July.
authors.affiliation: College of Pharmacy, Heilongjiang University of Traditional Chinese Medicine, Harbin 150040, China.
authors.forename: Hong-Hua
authors.initials: HH
authors.lastname: Cui
authors.forename: Zhen-Yue
authors.initials: ZY
authors.lastname: Wang
authors.forename: Zong-Quan
authors.initials: ZQ
authors.lastname: Wang
authors.forename: Rui-Ming
authors.initials: RM
authors.lastname: Li
authors.forename: Yi-Hua
authors.initials: YH
authors.lastname: Kang
mesh_terms: D000880:Anthraquinones / Q000032:analysis; D004642:Emodin / Q000031:analogs & derivatives / Q000032:analysis*; D005960:Glucosides / Q000032:analysis; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry* / Q000254:growth & development; D025341:Principal Component Analysis / Q000379:methods; D011786:Quality Control; D000077185:Resveratrol; D031804:Rumex / Q000737:chemistry* / Q000254:growth & development; D012621:Seasons; D013267:Stilbenes / Q000032:analysis
chemical_list: D000880:Anthraquinones; D005960:Glucosides; D013267:Stilbenes; C008905:physcione; D004642:Emodin; C027113:chrysophanic acid; D000077185:Resveratrol; C058229:polydatin