IN VITRO CHEMICAL AND BACTERIAL CHANGES IN SALIVA

¹ National Institute of Dental Research, National Institutes of Health, Bethesda 14, Md.

Bacterial and chemical changes in incubated saliva were studied. The saliva studied contained 170 to 226 µg carbohydrate as glucose, 404 to 713 µg total nitrogen, and 52 to 125 µg free ammonia nitrogen per milliliter, prior to incubation.

During incubation, the formation of ammonia and indole were markedly inhibited by the addition of glucose.

Lactobacillus and streptococcal populations were increased, or maintained, at a higher level in the presence of glucose. Fusiforms, on the other hand, grew and maintained themselves in the absence of glucose. Veillonella increased in numbers in saliva with added sodium lactate and to a lesser extent with added glucose.