Impact of increasing concentration of tart and sweet cherries juices concentrates on healthy mice gut microbiota

Abstract

Cherries are an excellent source of dietary polyphenols and are marketed as sports and health dietary supplements. However, there are still limited direct evidence for their purported nutritional and health benefits. Gut microbiota modulation ought to be tested because most polyphenols reach the colon where they undergo microbial metabolization to bioactive and bioavailable metabolites. In the present study, varying dilutions of three concentrate cherries juices, Montmorency tart cherry juice, Balaton tart cherry juice, and sweet cherry juice, were examined to determine their potential effect on the murine gut microbiota composition. Forty-five mice were randomly assigned to three different groups. Each group received an increased concentration of its assigned juices (1/20, 1/15, 1/10, 1/7, and 1/4 [v/v]) every 5 days for 25 days. Fecal samples were collected after each concentration change for microbiota characterization by high-throughput 16S rRNA gene sequencing using Illumina Miseq. The results revealed consistent gut microbiota modulation based on concentration regardless of the juice type, but not in a true dose-dependent manner. The two median concentrations and the two highest were significantly different from each other and from the baseline and lowest concentration. Increasing cherries consumption consistently resulted in significant increase of the relative abundance of Barnesiella and Akkermansia, whereas Bacteroides abundance was negatively correlated with the concentration of the juice. Overall, we demonstrate that cherries induce a beneficial modulation of the murine gut microbiota, and that amounts of fruits consumed need to be considered to devise appropriate health and nutrition studies.