title: [Study of antibacterial effect of Galla Chinensis on the bacteria biofilm in chemostat].
abstract: OBJECTIVE
  To compare the antibacterial effect of Galla Chinensis with that of chlorhexidine by means of chemostat and provide experimental foundation for caries prevention with Chinese medicine instead of chemicals in future.
  
  
  METHODS
  A multispecies consortium biofilm (BF) model was construted in the chemostat. The growth-inhibition on bacterial biofilm coated on HA was investigated by means of the colony-forming units (CFU). Acid-inhibition was inspected by continual pH-recording in the flow cells. And the profile on the biofilm treated by both experimental medicines was observed with the scanning electromicroscopy (SEM).
  
  
  RESULTS
  Both of the experimental medicines could inhibit the growth of the BF bacteria. And Galla Chinensis had no obvious influence on the ecological composing of the BF bacteria. Both of the experimental medicines could inhibit the acid producion of experimental bacteria. But the final pH of Galla Chinensis was lower than that of chlorhexidine. A typical biofilm formed on HA was observed by SEM. Both of Galla chinensis and chlorhexidine could inhibit the production of extracellular matrix and make the BF profile on the surface of the HA clearer and simpler.
  
  
  CONCLUSIONS
  Galla Chinensis had definite antibacterial effect. No obvious difference is found between Galla Chinensis (4 g x L(-1)) and chlorhexidine (0.5 g x L(-1)). Therefore, it is possible for Chinese medicine to gradually replace the chemical medicine in clinic and it will give a new choice for caries prevention.
authors.affiliation: West China College Stomatology of Sichuan University, Chengdu 610041, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Lh
authors.forename: Ji-yao
authors.initials: JY
authors.lastname: Li
authors.forename: Bing
authors.initials: B
authors.lastname: Zhu
authors.forename: Xue-dong
authors.initials: XD
authors.lastname: Zhou
mesh_terms: D000190:Actinomyces / Q000187:drug effects / Q000254:growth & development; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000891:Anti-Infective Agents, Local / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D002710:Chlorhexidine / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007313:Insecta / Q000737:chemistry; D008419:Materia Medica / Q000302:isolation & purification / Q000494:pharmacology*; D013295:Streptococcus mutans / Q000187:drug effects / Q000254:growth & development; D013298:Streptococcus sanguis / Q000187:drug effects / Q000254:growth & development
chemical_list: D000900:Anti-Bacterial Agents; D000891:Anti-Infective Agents, Local; D008419:Materia Medica; D002710:Chlorhexidine