title: [HPLC determination of chemical constituents produced in Radix Polygoni Multiflori after processing].
abstract: OBJECTIVE
  To analysis the changes of two chemical constituents, namely 2, 3-dihydro-3, 5- dihydroxy-6-methyl-4H-pyran-4-one (DDMP) and 5-hydryoxymethyl-furfural (5-HMF) produced in Radix Polygoni Multiflori after processing, with processing time, and to determine the contents of 5-HMF in samples of Radix Polygoni Multiflori and Radix Polygoni Multiflori preparata.
  
  
  METHODS
  An HPLC method was applied with a Zobax SB-C18 (3.9 mm x 150 mm, 5 microm) column by a elution using methanol-water (10: 90) as the mobile phase. The detection was set at UV 280 nm.
  
  
  RESULTS
  The contents of DDMP were increasing with the processing time until 24 hour, followed by a decrease until 60 hour process. The contents of 5-HMF were increasing gradually throughout the 60 hour steaming process. The contents of 5-HMF in 11 samples of Radix Polygoni Multiflori preparata were from 0.013% to 0.101%, and only one in 4 samples of Radix Polygoni Multiflori containing trace amount of 5-HMF.
  
  
  CONCLUSIONS
  The chemical components in Radix Polygoni Multiflori were changed during the processing procedures. Therefore, the processing of Radix Polygoni Multiflori should be controlled and standardized.
authors.affiliation: Institute of Chinese Medicine Basic Theory, Beijing 100700, China. zhen-li_liu@sina.com.cn
authors.forename: Zhen-Li
authors.initials: ZL
authors.lastname: Liu
authors.forename: Zhi-Qian
authors.initials: ZQ
authors.lastname: Song
authors.forename: Zhi-Mao
authors.initials: ZM
authors.lastname: Chao
authors.forename: Shu-Yi
authors.initials: SY
authors.lastname: Lv
authors.forename: Chun
authors.initials: C
authors.lastname: Wang
authors.forename: Lin-Fu
authors.initials: LF
authors.lastname: Li
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D019664:Polygonaceae / Q000737:chemistry*; D015203:Reproducibility of Results
chemical_list: D004365:Drugs, Chinese Herbal