title: Applications of microcalorimetry in the antibacterial activity evaluation of various Rhizoma coptidis.
abstract: BACKGROUND
  Various Rhizoma coptidis are commonly used in clinical applications due to their strong antibacterial effect.
  
  
  OBJECTIVE
  The antibacterial effect of various R. coptidis were evaluated by microcalorimetry together with statistical analysis.
  
  
  METHODS
  The dried roots of Coptis chinensis Franch, Coptis deltoidea C.Y. Cheng et Hsiao, and Coptis teeta Wall (Ranunculaceae) were identified by Prof. Xiao-He Xiao. The herbs were tested using thermal activity monitor (TAM) air isothermal microcalorimeter, ampoule mode, to evaluate the biological activity. The dynamic energy metabolism information about the Staphylococcus aureus growth at 37°C was analyzed with principal component analysis.
  
  
  RESULTS
  From the principle component analysis on quantitative parameters, the action of various R. coptidis on S. aureus growth at 37°C could be easily evaluated by analyzing the change of values of the two main parameters: the growth rate constant of first stage (k(1)) and the maximum heat rating of the first stage (P(1)). And the results of paired t-test show that there were no notable differences between inhibitory ratios calculated with k(1) and that of P(1). Using microdilution method, the minimal inhibitory concentrations (MIC) of C. chinensis, C. deltoidea, and C. teeta were detected, and they were 77.8 ± 2, 116.6 ± 4, 93.3 ± 2 μg/mL, respectively.
  
  
  CONCLUSIONS
  This work provided a useful method for the evaluation of antibacterial activity of various R. coptidis.
authors.affiliation: China Military Institute of Chinese Materia Medica, Military Hospital of China, Beijing, People's Republic of China. feng_xue789@yahoo.cn
authors.forename: Xue
authors.initials: X
authors.lastname: Feng
authors.forename: Dan
authors.initials: D
authors.lastname: Yan
authors.forename: Kui-Jun
authors.initials: KJ
authors.lastname: Zhao
authors.forename: Jiao-Yang
authors.initials: JY
authors.lastname: Luo
authors.forename: Yong-Shen
authors.initials: YS
authors.lastname: Ren
authors.forename: Wei-Jun
authors.initials: WJ
authors.lastname: Kong
authors.forename: Yu-Mei
authors.initials: YM
authors.lastname: Han
authors.forename: Xiao-He
authors.initials: XH
authors.lastname: Xiao
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology*; D002151:Calorimetry; D000089042:Coptis chinensis; D004365:Drugs, Chinese Herbal / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D018517:Plant Roots; D025341:Principal Component Analysis; D027343:Rhizome / Q000737:chemistry; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development
chemical_list: D000900:Anti-Bacterial Agents; D004365:Drugs, Chinese Herbal; C107393:Coptidis rhizoma extract