Bacterial activity of a new antiulcer agent, ecabet sodium, against Helicobacter pylori under acidic conditions

Abstract

Helicobacter pylori NCTC 11637, which is nonviable at pH 3.0, became viable after addition of 10 mM urea owing to ammonia production by urease. In a buffer supplemented with urea, ecabet sodium decreased both the production of ammonia and the number of viable cells of H. pylori NCTC 11637 and changed the bacteria from the bacilliform to the horseshoe or doughnut shape in a concentration-dependent manner. In particular, ecabet sodium (2 and 4 mg/ml) decreased the number of viable cells below the control level. Benzohydroxamic acid, a urease inhibitor, also caused a decrease in ammonia production accompanied by a decrease in the number of viable cells and changed the morphological form at pH 3.0, but the number of viable cells was not lowered below the control level. In buffers at various pHs without urea, ecabet sodium showed a concentrationdependent bactericidal effect on H. pylori at pHs 4.0 and 5.0 but not at pHs 6.0 and 7.0 while benzohydroxamic acid caused only a slight decrease in the number of viable cells at pH 4.0. These results suggest that ecabet sodium has strong bactericidal activity in addition to its urease-inhibiting activity under acidic conditions.

Influence of anti-ulcer drugs used in Japan on the result of 13 C-urea breath test for the diagnosis of Helicobacter pylori infection

“…Ecabet sodium exhibits a bactericidal effect against H. pylori by inhibiting the urease activity of the bacterium, or by a direct bactericidal effect under acidic conditions. 16 On the other hand, it has been reported that the D 13 C‰ in the UBT is significantly decreased after 4 weeks of administration of sucralfate. 17 In the present study, mucoprotective agents, such as polaprezinc, rebamipide, teprenone, cetraxate hydrochloride, sucralfate, and ecabet sodium, were evaluated for their possible effects on the results of the UBT.…”

“…[15][16][17] While the mechanism of action varies among drugs, these drugs are said to have direct antimicrobial activity, to inhibit the adhesion of H. pylori to the gastric mucosa, to inhibit the urease activity of H. pylori, to inhibit the protease/lipase activity of H. pylori, or to enhance the antimicrobial activity of antibiotics. 15 It is, therefore, necessary to determine whether mucoprotective agents can produce false-negative results in tests for H. pylori infection.…”

Antibacterial Activity of Hydrolyzable Tannins Derived from Medicinal Plants against Helicobacter pylori

“…Bactericidal activity was determined by using an in vitro killing assay (25,29,37). A bacterial suspension of H. pylori NCTC 11638 (100 µl, approximately 10 7 CFU/ml) was inoculated into 10 ml of 0.2% DMCD-supplemented PPLO broth alone or containing TG-I (12.5 to 50 µg/ml).…”

Antibacterial Activity of Ethanol Extract of Betel Leaf (Piper betle L.) Against Some Food Borne Pathogens

“…The effect of pH on the antibacterial activity of the ethanol extract of betel leaf was assayed following the method reported previously by Shibata et al (1995) 28 , and Ohno et al, (2003) 29 with slight modification. The 50mM citrate-phosphate buffer (pH 5.0), 50mM Phosphate buffer (pH 7.0), 20mM Tris-HCl buffer (pH 9.0) and 20mM Glycine-NaOH buffer (pH 10.0) were used in this assay.…”