Constipation is one of the most common gastrointestinal complaints worldwide. The aim of this study was to determine whether edible bifidobacteria (Bifidobacterium longum, B. infantis, B. animalis, B. bifidum, B. adolescentis or B. breve) exhibit interspecies differences in alleviating
constipation induced by
loperamide in BALB/c mice and to analyse the main reasons for the interspecies differences. BALB/c mice were given bifidobacteria by gavage once per day for 8 days. The primary outcome measures, which included related
constipation indicators, and the secondary outcome measures, which included changes in the concentration of
short-chain fatty acids in faeces and changes in the faecal flora, were used to evaluate the
therapeutic effects of the edible bifidobacteria on
constipation. The findings show that the six species of Bifidobacterium differed in their ability to relieve
constipation. B.
longum, B. infantis and B. bifidum were the most effective in relieving
constipation, B. adolescentis and B. breve were partially effective and B. animalis was not effective. Furthermore, edible Bifidobacterium treated
constipation by increasing the abundance of Lactobacillus and decreasing the abundance of Alistipes, Odoribacter and Clostridium. Higher concentrations of
short-chain fatty acids were found in the faecal samples from the edible Bifidobacterium treatment groups. Meanwhile, an increased concentration of
acetic acid could alleviate
constipation. In conclusion, edible bifidobacteria exhibit interspecies differences in the alleviation of
constipation. Meanwhile, bifidobacteria improved
constipation symptoms by increasing the concentration of
acetic acid and the relative abundance of Lactobacillus and reducing the content of Alistipes, Odoribacter and Clostridium.