Research
Good Bacteria
Part 1
The in vitro activity of vaginal Lactobacillus with
probiotic properties against Candida
Abstract
Strus
M, Kucharska A, Kukla G, Brzychczy-Wloch M, Maresz K,
Heczko PB.
Department
of Microbiology, Jagiellonian University Medical College,
Cracow, Poland.
Lactobacilli,
the predominant vaginal microorganisms in healthy premenopausal
women, control other members of the vaginal microflora
and thus protect against bacterial vaginosis and urinary
tract infections. It has been claimed that some lactobacilli
are also protective against Candida vaginitis. Little
is known, however, about the mechanisms by which these
lactobacilli can control vaginal populations of Candida
and prevent vaginitis. To address this question, vaginal
Lactobacillus strains with known antagonistic properties
against bacteria were tested for their cell surface
properties, adhesion to vaginal cell lines in vitro
and antagonistic activities against Candida. A small
proportion of the lactobacilli tested adhered strongly
to cultured vaginal epithelial cells and inhibited growth
of Candida albicans but not of C. pseudotropicalis.
This anticandidal activity was in some Lactobacillus
strains related to hydrogen peroxide (H2O2) production,
but catalase treatment did not suppress this activity
in other Lactobacillus strains, suggesting alternative
mechanism(s). Moreover, tested vaginal Candida strains
were resistant to relatively high concentrations of
H2O2 that markedly exceeded those produced by even the
most active Lactobacillus strains.