title: [Study on the influence on Rhizoma Corydalis by different harvest time and processing methods].
abstract: OBJECTIVE
  To choose the best harvest time and initial processing method of Rhizoma Corydalis.
  
  
  METHODS
  Taking the content of tetrahydropalmatine and dry rates as major indices, different samples from different harvest time and different processing methods were investigated by HPLC. The C18 column (250 mm x 4.6 mm, 5 microm) was used with mobile phase of methanol-0.1% phosphoric acid solution (pH = 6.0, adjusted with triethylamine) (58: 42). The mobile phase flow rate was 1.0 mL/min. The detection wavelength was 280 nm.
  
  
  RESULTS
  The contents of tetrahydropalmatine were similar although the harvest time was different. The dry rate on May 21 was higher than the others. The content of tetrahydropalmatine was the highest by steaming and reached 0.11%.
  
  
  CONCLUSIONS
  The best harvest time for Rhizoma Corydalis is around 10 days after the above-ground plant wilted, and the best initial processing method for Rhizoma Corydalis is steaming.
authors.affiliation: Zhejiang Institute of Traditional Chinese Medicine, Hangzhou 310023, China. jjren@163.com
authors.forename: Jiang-Jian
authors.initials: JJ
authors.lastname: Ren
authors.forename: Jian-Zhong
authors.initials: JZ
authors.lastname: Xu
authors.forename: Xu-Ping
authors.initials: XP
authors.lastname: Yu
mesh_terms: D001600:Berberine Alkaloids / Q000032:analysis* / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D031311:Corydalis / Q000737:chemistry* / Q000254:growth & development; D004365:Drugs, Chinese Herbal / Q000737:chemistry* / Q000302:isolation & purification; D006358:Hot Temperature; D010946:Plants, Medicinal / Q000737:chemistry* / Q000254:growth & development; D015203:Reproducibility of Results; D027343:Rhizome / Q000737:chemistry; D012621:Seasons; D013227:Steam; D013678:Technology, Pharmaceutical / Q000379:methods*
chemical_list: D001600:Berberine Alkaloids; D004365:Drugs, Chinese Herbal; D013227:Steam; C014215:tetrahydropalmatine