PROCESSES OF GASEOUS BIOMARKERS FORMATION in persistent Helicobacter pylori infection - BIOTECHNOLOGICAL MODEL

Abstract

To development a foundation of biotechnological process models occurring in the human stomach with the persistence of the Helicobacter pylori (HP) bacteria colonies. Observations in vivo were carried out on two groups of subjects: in 10 volunteers (22-55 years old) with known HP-status oral fluid parameters before and after ingesting a urea solution were studied. In addition, urease activity of urealiticum microflora of the oral cavity was investigated in 62 persons with unknown HP status (5 - 64 years old). Determining the level of ammonia was carried out by linearly coloristic method (detection limit 0.3 mg/m3) and by using a calibrated electrochemical sensor (detection limit 1,4 mg/m3).The biomarker pathways of ammonia resulted from the enzymatic hydrolysis of 500 mg urea by HP urease was analyzed. The levels of ammonia in mouth and stomach and the release time of the analyte were compared. The limit stage is the formation of ammonia in the stomach. The presence of urease producers in the oral cavity and the necessity of the addition of their products as a result of side reactions of urea hydrolysis were demonstrated. The process mechanism of ammonia forming and its mass balance were proposed. Based on the standard biosystem of Helicobacter pylori, a model of the derivation of gaseous ammonia as a biomarker of HP presence in the diagnosis of human gastrointestinal tract diseases was created. It allows an algorithm of analytical detection of the bacteria persistence to be built and the new diagnostic tools to be developed.