Gr. Tompkins et al., The effects of dietary ferric iron and iron deprivation on the bacterial composition of the mouse intestine, CURR MICROB, 43(1), 2001, pp. 38-42
The influence of dietary ferric iron on the intestinal microbiota of mice w
as investigated with a view to promoting benign lactic acid bacteria (which
have minimal iron requirements) in order to enhance colonization-resistanc
e potential. Three groups of eight mice received a diet differing only in i
ron content, for a period of 12 weeks. Dietary iron deprivation resulted in
overall increased small intestinal bacterial populations, including lactic
acid bacteria, but these differences were generally not significant (p > 0
.05). With the exception of coliforms, all examined bacterial groups (anaer
obes, micro-aerophiles, lactobacilli, and enterococci) were significantly (
p < 0.05) elevated in the colons of iron-deprived mice. The relatively low
numbers of total anaerobes in the colons of iron-replete and iron-overloade
d mice suggested that, as well as promotion of bacteria under iron-deprived
condition, provision of ferric iron suppressed bacteria, probably by oxida
tion of normally reduced environments.