OBJECTIVEUsing MBEC-Assay to assay minimal biofilm eradication concentration (MBEC) of Galla Chinensis and Nidus Vespae to oral bacterial biofilm. To set up traditional Chinese medicine susceptibility pharmacodynamic empirical study methods of oral bacterial biofilm.

METHODSCariogenic bacteria strains were selected (Streptococcus mutans ATCC 25175, Streptococcus sanguis ATCC 10556, Lactobacillus rhamnosus AC 413, Actinomyces naeslundii WVU 627) in this study. Extraction components of Galla Chinensis were GCE (aqueous extract), GCE-B (30% alcohol extract) and extraction components of Nidus Vespae were NVE1 (95% alcohol extract). (1) To observe oral bacterial biofilm formatiom in MBEC-Device at different time. (2) MBEC-HTP-Assay: The minimal inhibitory concentration (MIC) and minimal biofilm eradication concentration (MBEC) of GCE, GCE-B and NVE1 to oral bacteria strains were determined.

RESULTSOral bacterial biofilm were readily formed on the lid of MBEC-Device under selected condition (observed by SEM). Oral cariogenic bacteria growing as plankton populations were sensitive to GCE, GCE-B and NVE1. To GCE, GCE-B and NVE1, oral cariogenic bacterial biofilm were 2-16 times less susceptible than growing plankton bacteria. GCE and GCE-B were the most effective medicine against oral cariogenic bacterial biofilm. NVE1 were effective in killing oral-bacterial biofilm at relatively high concentration.

CONCLUSIONGCE and GCE-B were effective medicine against oral cariogenic bacterial biofilm. MBEC (minimal biofilm eradication concentration) can provide a relative accurate medicine concentration for clinical test.