Journal of Dental Research, Vol 64, 1016-1018, Copyright © 1985 by International & American Associations for Dental Research Online Journals
Effect of anti-oxidants on growth and lactic acid production by Streptococcus mutans
L. I. Kupp, S. Rosen and F. M. Beck
The effects of three anti-oxidants--tertiary butylhydroquinone (TBHQ),
butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT)--on both
growth and lactic acid production by eight cariogenic strains of
Streptococcus mutans were investigated. Synergistic inhibitory effects of
potassium sorbate on lactic acid production were also determined. All three
anti-oxidants are phenolic derivatives and are commonly used in food
systems due to their excellent "carry-through" properties during
processing. Growth inhibition was determined by turbidity measurements at
600 nm. Lactic acid was assayed by gas chromatography, and bacterial DNA
was assayed by the diphenylamine reaction. There were reduced growth levels
of S. mutans due to the anti-oxidants and potassium sorbate for at least 12
hr, with TBHQ and BHA still inhibiting growth at 24 hr. Nearly all
concentrations of anti-oxidants and potassium sorbate reduced lactic acid
production by S. mutans, but only TBHQ significantly inhibited lactic acid
production when the amount of acid per microgram DNA was calculated. A
synergistic reduction of lactic acid production by S. mutans does occur in
most combinations of potassium sorbate with anti-oxidants.
