title: [Content comparison of pinoresinol diglucoside in original and reborn bark of Eucommia ulmoides].
abstract: OBJECTIVE
  To evaluate the reborn barks quality, antihypertensive effective component of pinoresnol diglucoside (PDG) in three times reborn barks were determined.
  
  
  METHODS
  A YWG C18 column (10 microm, 250 x 4.6 mm) was used with a mobile phase of methanol-water (30:75) and flow rate of 1.0 (ml/min). The detective wave-length was set at 277nm and the column temperature at room temperature.
  
  
  RESULTS
  PDG in the first reborn barks are slightly higher than the original ones, and in the second reborn barks are similar with the barks before girdling (the fist reborn barks), but in the third reborn barks, PDG are much lower than the barks before girdling (the second reborn barks).
  
  
  CONCLUSIONS
  In order to ensure reborn barks quality, we suggest that the girdling bark regeneration can be made two times, the time between the first and the second girdling is not less than five years. PDG in the third reborn barks should be enhanced.
authors.affiliation: Biology and Medicine Key Laboratory of Northwest University, Xi'an 710069, China.
authors.forename: Suo-Min
authors.initials: SM
authors.lastname: Feng
authors.forename: Zhi-Jie
authors.initials: ZJ
authors.lastname: Gan
authors.forename: Xi-Feng
authors.initials: XF
authors.lastname: Zhai
authors.forename: Peng-Fei
authors.initials: PF
authors.lastname: Fu
authors.forename: Wen-Ji
authors.initials: WJ
authors.lastname: Sun
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003247:Conservation of Natural Resources; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification; D031283:Eucommiaceae / Q000737:chemistry* / Q000378:metabolism; D017705:Lignans / Q000096:biosynthesis / Q000302:isolation & purification*; D024301:Plant Bark / Q000033:anatomy & histology / Q000737:chemistry / Q000378:metabolism; D010946:Plants, Medicinal / Q000737:chemistry*; D012038:Regeneration; D013997:Time Factors; D014465:Ultrasonics
chemical_list: D004365:Drugs, Chinese Herbal; D017705:Lignans; C013200:pinoresinol diglucoside