Evaluation of the prebiotic potential of five kiwifruit cultivars after simulated gastrointestinal digestion and fermentation with human faecal bacteria

We studied the invitro prebiotic potential of five different cultivars of kiwifruit including the green-fleshed Hayward' and Zesh004' and the gold-fleshed Hort16A', Zesy002' and Zesy003'. The kiwifruit (25g fresh weight equivalent) were subjected to simulated gastrointestinal digestion before fermentation for 16h with faecal microbiota from ten individual donors. Microbial metabolites including lactate were quantified while changes in microbiome composition were determined by 16S rRNA sequencing. Lactate concentrations were highest with Hayward' (P=0.01) and correlated with the amount of the kiwifruit fibre and polyphenols, chlorogenic acid and cryptochlorogenic acid. All the kiwifruit behaved similar to inulin in increasing the relative abundance of Bifidobacterium (P<0.001), but unlike inulin, significantly (P<0.001) increased the abundances of Ruminococcaceae and decreased Bacteroides. In comparison with inulin, the green-fleshed kiwifruit selectively increased Lachnospira (P=0.008) while the gold-fleshed kiwi fruit increased Akkermansia (P<0.001). These data suggest that the fibre and polyphenol content of the kiwifruit play a role in modulating gut microbial metabolism. Further clinical studies with these kiwifruit cultivars are required to confirm the potential prebiotic benefits that may be achieved by normal dietary intervention.