Comparison of Five Selective Media for the Growth and Enumeration of Streptococcus Mutans

Background: Although a few growth media are available for selective isolation of the cariogenic bacteria, Streptococcus mutans (S. mutans), it is still unclear as to which is the most efficacious. This study compared the selectivity and sensitivity of five different media for growing a laboratory strain of S. mutans (NCTC 10449), and for enumerating S. mutans from teeth of a group of young children, aged 2–10 years. Methods: The media tested in this study were mitis salivarius with bacitracin (MSB), mitis salivariuskanamycin‐bacitracin (MSKB), glucose‐sucrosetellurite‐bacitracin (GSTB), trypticase soy‐sucrosebacitracin (TYS20B) and tryptone‐yeast‐cysteinesucrose‐bacitracin (TYCSB) agars. These were prepared according to the respective manufacturer's instructions. Results: The results showed that at concentrations of bacteria 1times103 to 1X1010/mL, the recovery of the laboratory S. mutans strain was highest in TYCSB agar, followed by in descending order by TYCSB, MSB, GSTB, and MSKB (p