title: [Effects of post-harvest processing and extraction methods on polysaccharides content of Dendrobium officinale].
abstract: OBJECTIVE
  To reveal the quality variation of polysaccharide in Dendrobium officinale by post-harvest processing and extraction methods, and provide a basis for post-harvest processing and clinical and hygienical applications of Tiepifengdou (Dendrobii Officinalis Caulis).
  
  
  METHODS
  The content of polysaccharides were studied by 4 post-harvest processing methods, i. e. drying by drying closet, drying after scalding by boiling water, drying while twisting, and drying while twisting after scalding by boiling water. And a series of temperatures were set in each processing procedure. An orthogonal test L9 (3(4)) with crushed degrees, solid-liquid ratio, extraction time and extraction times as factors were designed to analyze the dissolution rate of polysaccharides in Tiepifengdou processed by drying while twisting at 80 degrees C.
  
  
  RESULTS
  The content of polysaccharides was ranged from 26.59% to 32.70% in different samples processed by different processing methods, among which drying while twisting at 80 degrees C and 100 degrees C respectively were the best. Crushed degree was the most important influence on the dissolution rate of polysaccharides. The dissolution rate of polysaccharides was extremely low when the sample was boiled directly without crushing and sieving.
  
  
  CONCLUSIONS
  Drying while twisting at 80 degrees C was the best post-harvest processing method, which can help to dry the fresh herbs and improve the accumulation of polysaccharides. Boiling the uncrushed Tiepifengdou for a long time as traditional method could not fully extract polysaccharides, while boiling the crushed Tiepifengdou can efficiently extract polysaccharides.
authors.affiliation: Nurturing Station for State Key Laboratory of Subtropical Silviculture, Zhejiang Agricultural and Forestry University, Zhejiang Provincial Strategic Alliance for Technical Innovation in Industry of Dendrobium officinale, Lin'an 311300, China. lenilc@163.com
authors.forename: Cong
authors.initials: C
authors.lastname: Li
authors.forename: Li-Dan
authors.initials: LD
authors.lastname: Ning
authors.forename: Jin-Ping
authors.initials: JP
authors.lastname: Si
authors.forename: Ling-Shang
authors.initials: LS
authors.lastname: Wu
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Liu
authors.forename: Xian-Shui
authors.initials: XS
authors.lastname: Song
authors.forename: Qiao-Xian
authors.initials: QX
authors.lastname: Yu
mesh_terms: D005591:Chemical Fractionation / Q000379:methods*; D031667:Dendrobium / Q000737:chemistry* / Q000254:growth & development; D003890:Desiccation; D004365:Drugs, Chinese Herbal / Q000737:chemistry* / Q000302:isolation & purification*; D016014:Linear Models; D011134:Polysaccharides / Q000032:analysis*; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D004365:Drugs, Chinese Herbal; D011134:Polysaccharides; D014867:Water