A Study on Acid Resistance of Helicobacter pylori

Physiological saline solutions, each adjusted to p H 1.0, p H 2.0 and p H 7.2, and added urea andurease inhibitor (Acetohydroxamic acid), were inoculated with a culture solution of Helicobacter pyloriNCTC11637 strain derived from man, and allowed to react for 10, 30, 60 and 120 minutes. After fivedays of incubation on a blood agar medium, remaining viable H. pylori was counted. Survival of H.pylori was inadequate under the conditions of p H 1.0 and p H 2.0, but survival up to 120 min wasobserved on addition of urea. Further, on addition of urease inhibitor the survival time was reduced. H. pylori survived under the condition of p H 7.2 independent of addition of urea and urease inhibitor. Ureais essential for survival of H. pylori under strongly acidic conditions, and utility of urease inhibitor wasobserved for inhibition of survival of H. pylori.