Nitrate-Reducing Oral Bacteria: Linking Oral and Systemic Health

Part of the Nutrition and Health book series (NH)


There is now an established role for oral nitrate-reducing bacteria in the maintenance of endogenous nitric oxide production in humans. Inorganic nitrate, primarily from green leafy vegetables, is taken up in the proximal gut and concentrated in salivary glands. Upon salivation, nitrate is reduced by specific and selective nitrate-reducing bacteria to nitrite. Nitrite-enriched saliva when swallowed generates nitric oxide gas in the lumen of the stomach due to acid disproportionation of nitrite. This nitrate–nitrite–nitric oxide pathway is a redundant NO-generating system that can, perhaps, compensate for loss of enzymatic NO production from NOS. This chapter will highlight the importance of oral bacteria in this pathway and future therapeutic strategies aimed at repleting NO production.


Denitrifying bacteria Dietary nitrate Nitrite Periodontitis Hypertension Stomach acid 


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Department of Molecular and Human GeneticsBaylor College of MedicineHoustonUSA
  2. 2.Virolology & MicrobiologyBaylor College of MedicineHoustonUSA

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