title: [Effect of concentration of catalpol and 5-hydroxymethyl-2-furaldehyde from processing of Rehmanniae Radix].
abstract: OBJECTIVE
  To study on effect of concentration of catalpol and 5-hydroxy methyl-2-furaldehyde (5-HMF) from Rehmanniae Radix at various processing.
  
  
  METHODS
  The Rehmanniae Radix was dried and prepared from the steaming process with 10% ethanol, 50% ethanol at 90 degrees C and 100 degrees C each other. And the changes of catalpol and 5-HMF was determinated. The extraction of 5-HMF and catalpol was sonicated in 30% methanol for 2 h. The analysis of 5-HMF and catalpol was conducted by HPLC with reversed-phase C-18 column and detected under UV 284 nm, 204 nm. Elution was carried out at 1.0 mL min(-1) with 3% acetonitrile.
  
  
  RESULTS
  From this analysis, we found out that the content of catalpol was decreased with the number of processing times, and content of 5-HMF was increased with the number of processing times at various processing. The temperature and concentration of ethanol can effect on content of catalpol and 5-HMF at processing. The Cooked Rehmanniae Radix processed at 100 degrees C, 10% ethanol is best. And the content of 5-HMF processed for more than 7 times was accorded with standard of Korea phamcopoetia.
  
  
  CONCLUSIONS
  Analyze the effect of concentration of catalpol and 5-HMF from Rehmanniae Radix at various processing, and provide the foundation for further study.
authors.affiliation: Department of Oriental Pharmaceutical Sciences, College of Phamacy, Kyung Hee University, Seoul 130701, Korea.
authors.forename: Mei-fen
authors.initials: MF
authors.lastname: Zhu
authors.forename: Xiang-qian
authors.initials: XQ
authors.lastname: Liu
authors.forename: Oh
authors.initials: O
authors.lastname: Ju-hee
authors.forename: Yook
authors.initials: Y
authors.lastname: Chang-soo
authors.forename: Lee
authors.initials: L
authors.lastname: Je-Hyun
mesh_terms: D002851:Chromatography, High Pressure Liquid; D000431:Ethanol; D005662:Furaldehyde / Q000031:analogs & derivatives* / Q000032:analysis; D005960:Glucosides / Q000032:analysis*; D006358:Hot Temperature; D057888:Iridoid Glucosides; D039823:Iridoids / Q000032:analysis*; D035281:Plant Tubers / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D032267:Rehmannia / Q000737:chemistry*; D013678:Technology, Pharmaceutical / Q000379:methods