Nitrate‐reducing microorganisms in the gastric juice of patients with stomach cancer — Experimental data and considerations upon the role of these microorganisms in gastrocarcinogenesis

Abstract

During recent years evidence has been accumulated supporting the hypothesis according to which nitroso compounds are involved in the generation of stomach cancer in humans. The present report deals with the occurrence and content of nitrite, nitrate and nitrosamines in the gastric juice of stomach cancer patients with special reference to nitrate-reducing microorganisms. Microorganisms were found to be present in gastric juice in all cases of cancer, mean total count being (5.6 +/- 2.4) log/ml (mean +/- standard deviation) and with limit values 1.4-8.0 log/ml. Nitrate-reducing microorganisms were found in 9 cases from 10. Their mean counts were (5.2 +/- 2.5) log/ml and limit values less than 0.5-8.0 log/ml. The role of nitrate-reducing microorganisms in the formation of nitrite and carcinogenic nitroso compounds is discussed. Some practical measures to control the count of nitrate-reducing microorganisms in stomach are presented.

N‐nitrosodimethylamine, nitrate and nitrate‐reducing microorganisms in human milk

“…The presence of nitrite in supernatant before reduction had been checked by a Griess reagent. The method of quantitative determination of nitrate-reducing microorganisms on the basis of the most probable numbers method ("multiple tube dilution to extinction") was employed to study the total counts and the counts of nitrate-reducing microorganisms in nitrate broth medium (6).…”