Researchers from the University of Valencia tested several strains of bifidobacteria isolated from the feces of breast-fed infants for activity against H pylori. They identified one strain, Bifidobacterium bifidum CECT 7366, which under certain conditions offered an inhibition level of nearly 95 percent in vitro and subsequently tested its effectiveness against infection in mice.

After 21 days, mice treated with the strain developed significantly fewer ulcers than the control group. Additional tests suggested treatment also partially relieved damage to gastric tissue caused by H pylori infection.

Reporting their findings in the journal Applied and Environmental Microbiology, the researchers said: “H pylori is considered one of the major risk factors underlying the development of gastritis and gastric and duodenal ulcers. Currently, antibiotic-based treatment for H pylori infection is neither sufficient nor satisfactory, with the most successful treatments reaching 75 percent to 90 percent eradication rates.

“The use of probiotics is a potentially promising tool to prevent H pylori. The results presented here confer to strain B bifidum CECT 7366 the status of a probiotic bacterium with functional activity against H pylori. Human clinical trials must be performed before commercialization of this strain can be approved.”

Applied and Environmental Microbiology is published by the Washington, D.C.-based American Society for Microbiology.