Bacterial Infections
Probiotics are believed to be involved with several mechanisms that influence the growth of pathogenic bacteria and their toxic byproducts acting on the body's own natural defense mechanisms
(Naidu AS et al., 1990).
In vitro,
bifidobacteria
have demonstrated an impact on a number of pathogenic microorganisms such as
Escherichia coli,
Staphylococcus aureus,
Salmonella typhi,
Schigella dysenteriae
and
Candida albicans. The action exhibited by these
bifidobacteria
is due in part to the production of substances such as bacteriocins and peroxides, but also to the production of organic acids such as lactic acid and acetic acid, thus reducing the intestinal pH, antagonizing the growth of certain microorganisms, and therefore helping the normal function of the intestinal flora
(Tannock, 1984;
Mallet AK et al., 1989;
Fons et al., 2000).
One of the most recently researched bacteria in this regard is
H. pylori. Studies suggest that the regular ingestion of
Lactobacillus-containing probiotics may have an effect on
H. pylori
(Wang KY et al., 2004). Several
in vitro
and animal studies have also shown an effect of a variety of
Lactobacillus
strains on the viability of
H. pylori
and adhesion of the bacteria to human intestinal mucosal cells
(Aiba Y et al., 1998). A recent review of 13 clinical trials, which included six in which patients were given only probiotics and seven in which they were given probiotics in addition to antibiotic therapy, reported the effect of probiotics on
H. pylori
growth. Trials in which fermented milk products were used tended to show better results than when the probiotic was taken in the form of bacteria alone
(Hamilton-Miller, 2003).
Introduction
Bacterial Infections
