title: [Qualities of Whitmania pigra in different-month-age and best harvest time].
abstract: OBJECTIVE
  Dynamic changes of quality and growth of Whitmania pigra were investigated to provide theoretical basis for quality control and determination of optimal harvest time.
  
  
  METHODS
  The contents of moisture, ethanol-soluble extractive, total ash, and acid-insoluble ash, as well as antithrombin activity were determined according to Chinese pharmacopoeia (2005 edition).
  
  
  RESULTS
  Qualities of W. pigra collected from different growth stages met the standards of Chinese pharmacopoeia (2005 edition). The highest amount of ethanol-soluble extract was found in 9-month-old, W. pigra, followed by 6-month-aged ones. And there was significant difference between 9-month-old and 4-month-old, 7 month-old and 11 month-old (P < 0.05). The highest antithrombin activity was detected in 6 month-old W. pigra, followed by 10 month-old. Significant differences of antithrombin activity were found between 6-month-old and 4 month-old ones, and 5 month-old (P < 0.05), however, there were no significant difference between 6 month-old ones with other samples. Eleven-month-old W. pigra got the most dry weight, and there were significant difference between 11 month-old ones with other samples (P < 0.05).
  
  
  CONCLUSIONS
  November, namely for 6 month old artificial cultivated W. pigra was the best harvest time in Jiangsu and Zhejiang provinces.
authors.affiliation: Institute of Chinese medicinal materials, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Hongzhuan
authors.initials: H
authors.lastname: Shi
authors.forename: Qiaosheng
authors.initials: Q
authors.lastname: Guo
authors.forename: Shusong
authors.initials: S
authors.lastname: Lu
authors.forename: Hui
authors.initials: H
authors.lastname: Li
mesh_terms: D000818:Animals; D000990:Antithrombin III; D000991:Antithrombins / Q000032:analysis; D002681:China; D007865:Leeches / Q000737:chemistry* / Q000254:growth & development*; D008516:Medicine, Chinese Traditional; D010446:Peptide Fragments
chemical_list: D000991:Antithrombins; D010446:Peptide Fragments; C101078:antithrombin (342-347); D000990:Antithrombin III