Abstract:

Objective:The aim of this study is to examine effects of para-aminobenzoic acid (PABA) on the growth ofStreptococcus mu- tans(S.mutans).Methods:Different concentrations of PABA (10-10~10-3gPL) were separately transferred to modified Carlsson medium.S.mutans(ATCC 25175) grew in modified Carlsson mediumwith different concentrations of PABA. All cultureswere incubated at 37eanaerobically in an atmosphere of 80% of nitrogen (vPv), 10% of hydrogen (vPv) and 10% of carbon dioxide (vPv) for 48 hours. The absorbance values ofS.mutanswere measured by using a spectrometer (UV-1601). The colony forming units (CFU) were obtained by growingS.mutansinmediawith different concentrations of PABA(10-10~10-3gPL).Results:Dif- ferent concentrations of PABAhad different stimulating effects on the growth ofS.mutans(P<0.05). But this kind of stimulat- ing effects declined when the concentration of PABAwas 10-3gPL.Conclusion:This experiment indicates PABAhas stimulating ef- fects on the growth ofS.mutans, and PABA can promote growth ofS.mutans.

Key words: Streptococcus mutans, para-aminobenzoic acid, microbial ecology