Materials and methods: Dissolving the AMPs into PBS and the sterilized saliva. Evaluating the inhibition of different concentration AMPs to Blastomyces albicans and Staphylococcus aureus by antibiotic-susceptive test paper. Preparing the broth of E.coli (1×105 cfu /ml)，adding the different concentration AMPs to the Broth of E.coli, after incubated for 0.5～6 hours , measuring the OD and evaluating the inhibition of AMPs in different concentration to E.coli. The inhibitory effect of Streptococcus mutans was measured by slip diffusion method. The minimal inhibitory concentration (MIC) was also determined.
Results: When the concentration of AMPs added to Broth of E.coli is 150µmol/L and 300µmol/L , the bacterium count is 0, but the control is 6700～9200cfu/ml. At 100µg/tablet AMPs, the diameter of inhibitor zones of Staphylococcus aureus ,Blastomyces albicans and Streptococcus mutans are respectively 13mm , 11 mm and 19mm; At 300µg/tablet , the diameter are 16 mm , 17mm and 21mm respectively. The minimal inhibitory concentration (MIC) of AMPs to Streptococcus mutans was 200µmol/L which determined by liquid culture medium. The antimicrobial activity of AMPs dissolved in PBS and saliva is similar .
Conclusions: The antibacterial activity of AMPs on blastomyces albicans, E.coli , Staphylococcus aureus and streptococcus mutans in vitro was significant, indicating that AMPs can be used as an agent for prevention of denture stomatitis and other oral infection.