The effect of smokeless-tobacco extracts on the growth of oral bacteria of the genus Streptococcus.

Aqueous tobacco extracts were used to supplement a basic salts solution (BSS) and a microbial medium. Thin-layer chromatography revealed sucrose in only one of four extracts. Discs saturated with extracts (0.1-50 mg/ml) failed to inhibit growth of any of the micro-organisms. Supplementation (10 mg/ml) of BSS with the tobaccos lacking sucrose resulted in augmented growth of Streptococcus mutans, Streptococcus salivarius and Streptococcus sanguis whereas the sucrose-containing brand augmented only Strep. sanguis growth. Thus extracts of these smokeless tobaccos would serve as a growth substrate for three species of oral streptococci which are frequently associated with human dental caries.