Isolation of Helicobacter Pylori from Raw Milk and Study on Its Survival in Fermented Milk Products

This research aimed to know if raw milk is a possible source of Helicobacter. pylori infection to human and assessing the inhibitory effect of fermented milk products on H. pylori growth. Sixty samples of cows' milk and raw marketable milk (30 samples each) were tested to detect H. pylori and were collected from farms and supermarkets in Assiut City, Egypt. The pathogen could be isolated from 13.33 and 6.66 % of cows' milk and marketable milk, respectively, by using the conventional culture method. Confirmation of the isolated strains using the PCR technique revealed that, 50% of the isolated strains were positive for the 16S rRNA gene. The strong antibiogram of Lactobacillus acidophilus was evident, where the count of the testedtwo strains of H. pylori (S1 and S2) was sharply decreased to 2.6 and 2.17 log cfu/ g yoghurt and 2.47 and 3.04 log cfu/ ml rayeb at the time of fermentation and could not be isolated at the first day. In case of Bifidobacterium bifidum, the count of S1 and S2 on the first day was 2.3 and 2.77 log cfu/ g yoghurt and 2.95 and 2.7 log cfu/ ml rayeb. Regarding the viability, H. pylori strains have remained viable for two days in yoghurt that was not supplemented with probiotics and could survive for seven days in control milk samples. There was no significant difference between the growth patterns of S1 and S2 in all treatments. Finally, fermented milk products containing probiotics were more effective in the survival of H. pylori than fermented milk products with no probiotics with a significant difference (P-value < 0.05).