The Effects of Osmolarity on the Growth of Streptococcus Mutans and Other Streptococcal Odontopathogens
Streptococcus mutans (S. mutans) has been of interest to dental researchers because of its abundance in the oral cavity and presence in carious lesions. Furthermore, experimental results in the last twenty years have provided sufficient evidence that these microorganisms are one of the etiological agents of dental caries. This study focuses on the effects of osmolarity on the growth initiation of S. mutans and other oral streptococci. A total of thirteen strains and one recent isolate were grown in different concentrations of glucose, sucrose, and xylitol. All experiments were done with both trypticase soy agar and trypticase soy broth. Colony forming units were counted as a measure of growth for the agar runs while absorbance readings were used as a measure of growth for the broth runs. Data were analyzed graphically and statistically. Comparisons were made between animal S. mutans, human S. routans, oral S. mutans, and oral non S. mutans. Tentative results imply that oral animal S. mutans is the most osmo-tolerant of all groups examined. There is also strong evidence that S. mutans have the ability to use the protein fragments present in the media for survival in the absence of carbohydrates.