Presence of Lactobacillus casei in saliva from children and adults using a new medium.

The aim of this study was to devise a medium for cultivation of L. casei and to compare the presence of L. casei in saliva from children and adults. The new medium was produced by omitting the sugars from Rogosa SL agar medium and supplementing this medium with melezitose. Although all tested strains of lactobacilli grew on the new medium, the facultatively homofermentative lactobacilli, L. casei and L. plantarum, could be identified by a typical colonial morphology. L. casei was the most common species of oral lactobacilli in saliva from children and made up a significantly higher proportion of the salivary lactobacillus flora in children than in adults.