title: The in vitro study of ursolic acid and oleanolic acid inhibiting cariogenic microorganisms as well as biofilm.
abstract: OBJECTIVE
  The aim of this study was to examine the effect of ursolic acid (UA) and oleanolic acid (OA), triterpenoid compounds that are isolated from many edible and medicinal plants, on cariogenic microorganisms and biofilms.
  
  
  METHODS
  A microtitre plate dilution assay was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of UA and OA against two Actinomyces spp. and four Streptococcus spp. The antibacterial activity of UA and OA was assessed by crystal violet staining, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM).
  
  
  RESULTS
  UA and OA displayed differential antibacterial activities against the six tested bacteria, with UA showing greater antibacterial activity than OA. Furthermore, the two drugs had greater antibacterial activity against Actinomyces spp. than Streptococcus spp. UA and OA at 1/4 MIC can reduce bacterial biofilm formation, whereas higher UA concentrations displayed antibacterial activity against Actinomyces viscosus and Streptococcus mutans in mature biofilms. For instance, 2.0 mg ml(-1) UA was sufficient to kill an A. viscosus biofilm.
  
  
  CONCLUSIONS
  UA and OA inhibit the growth of cariogenic microorganisms, which suggests that UA and OA have considerable potential as antibacterial agents for dental caries prevention.
authors.affiliation: School of Stomatology, Zhengzhou University, Zhengzhou, China.
authors.forename: L
authors.initials: L
authors.lastname: Zhou
authors.forename: Y
authors.initials: Y
authors.lastname: Ding
authors.forename: W
authors.initials: W
authors.lastname: Chen
authors.forename: P
authors.initials: P
authors.lastname: Zhang
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.forename: X
authors.initials: X
authors.lastname: Lv
mesh_terms: D000190:Actinomyces / Q000187:drug effects*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects*; D003731:Dental Caries / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D009828:Oleanolic Acid / Q000494:pharmacology*; D013291:Streptococcus / Q000187:drug effects*; D014315:Triterpenes / Q000494:pharmacology*; D000097245:Ursolic Acid
chemical_list: D000890:Anti-Infective Agents; D009828:Oleanolic Acid; D014315:Triterpenes; D000097245:Ursolic Acid
keywords: Actinomyces viscosus; Streptococcus mutans; biofilm; oleanolic acid; ursolic acid