Silva Mendez L S, Allaker R P, Hardie J M, Benjamin N
Department of Clinical Pharmacology, St Bartholomew's and the Royal London School of Medicine and Dentistry, United Kingdom.
Oral Microbiol Immunol. 1999 Dec;14(6):391-2. doi: 10.1034/j.1399-302x.1999.140612.x.
The antimicrobial agent nitric oxide (NO) is formed in the mouth and its concentration is directly related to salivary nitrite, which in turn is related to dietary nitrate intake. The aim of this study was to determine whether nitrite under acidic conditions will have an inhibitory effect, possibly occurring through NO production, on Streptococcus mutans, Lactobacillus casei and Actinomyces naeslundii. Whereas the growth of S. mutans was inhibited by a more acid pH, the addition of nitrite caused a marked, further dose-dependent reduction in bacterial numbers after 24 h of exposure. Similar effects were observed with A. naeslundii and L. casei. The ability of these bacteria to recover from nitrite exposure was also markedly affected by nitrite concentration. At acidity levels below pH 7, low concentrations of nitrite (0.2 mM) caused effective complete killing of S. mutans, with similar effects on the other organisms tested. These results demonstrate the possibility that nitrite in saliva has an effect on the growth and survival of cariogenic bacteria.
抗菌剂一氧化氮（NO）在口腔中形成，其浓度与唾液亚硝酸盐直接相关，而唾液亚硝酸盐又与膳食硝酸盐摄入量有关。本研究的目的是确定酸性条件下的亚硝酸盐是否会通过产生NO对变形链球菌、干酪乳杆菌和内氏放线菌产生抑制作用。虽然更酸性的pH值会抑制变形链球菌的生长，但添加亚硝酸盐在暴露24小时后会导致细菌数量显著进一步呈剂量依赖性减少。在内氏放线菌和干酪乳杆菌中也观察到了类似的效果。这些细菌从亚硝酸盐暴露中恢复的能力也受到亚硝酸盐浓度的显著影响。在pH值低于7的酸度水平下，低浓度的亚硝酸盐（0.2 mM）能有效完全杀死变形链球菌，对其他受试生物也有类似效果。这些结果表明唾液中的亚硝酸盐可能对致龋菌的生长和存活有影响。
