title: Application of microscopy technique and high performance liquid chromatography for quality assessment of Polygonum multiflorum Thunb. (Heshouwu).
abstract: BACKGROUND
  The technique of microscopy has been applied for identification of Chinese materia medica (CMM) since decades. However, very few scientific publications report the combination of conventional microscopy and high performance liquid chromatography (HPLC) techniques for further application to quality assessment of CMM.
  
  
  OBJECTIVE
  The objective of this study is to analyze the quality of the dried root tuber of Polygonum multiflorum Thunb. (Heshouwu) and to establish the relationships between 2,3,5,4'-tetrahydroxystilbene-2-O-β-glucoside, combined anthraquinone (CAQ) and quantity of clusters of calcium oxalate.
  
  
  METHODS
  In this study, microscopy and HPLC techniques were applied to assess the quality of P. multiflorum Thunb., and SPSS software was used to establish the relationship between microscopic characteristics and chemical components.
  
  
  RESULTS
  The results showed close and direct correlations between the quantity of clusters of calcium oxalate in P. multiflorum Thunb. and the contents of 2,3,5,4'-tetrahydroxystilbene-2-O-β-glucoside and CAQ. From these results, it can be deduced that Polygoni Multiflori Radix with a higher quantity of clusters of calcium oxalate should be of better quality.
  
  
  CONCLUSIONS
  The established method can be helpful for evaluating the quality of CMM based upon the identification and quantitation of chemical and ergastic substance of cells.
authors.affiliation: School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian, China ; School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China.
authors.forename: Li
authors.initials: L
authors.lastname: Liang
authors.affiliation: School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China.
authors.forename: Zhongzhen
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian, China.
authors.forename: Tingguo
authors.initials: T
authors.lastname: Kang
keywords: 2,3,5,4’-tetrahydroxystilbene-2-O-β-glucoside; Polygonum multiflorum Thunb; clusters of calcium oxalates; combined anthraquinone; quantitative analysis