抄録
Nitrate-reducing activity in the human oral cavity was demonstrated at the dorsum linguae; no nitrite formation was detected at other positions, such as the hard palate, soft palate, lingual abdomen and buccal surface. Furthermore, sufficient nitrite to account for the nitrite present in human saliva was formed very quickly at the dorsum linguae.
Assuming that the activity at the dorsum linguae was due to the action of a tissue enzyme present there, we analyzed this reaction kinetically. The substrate concentration at which maximum velocity was observed was approximately 0.05M and the Michaelis constant, Km, was approximately 0.012M.