Consumption of kiwifruit capsules increases<i>Faecalibacterium prausnitzii</i>abundance in functionally constipated individuals: a randomised controlled human trial

This study investigated the impact of ACTAZIN™ green (2400 and 600 mg) and Livaux™ (2400 mg) gold kiwifruit supplements on faecal microbial composition and metabolites in healthy and functionally constipated (FC) participants. The participants were recruited into the healthy group (<i>n</i> 20; one of whom did not complete the study) and the FC group (<i>n</i> 9), each of whom consumed all the treatments and a placebo (isomalt) for 4 weeks in a randomised cross-over design interspersed with 2-week washout periods. Modification of faecal microbiota composition and metabolism was determined by 16S rRNA gene sequencing and GC, and colonic pH was calculated using SmartPill^® wireless motility capsules. A total of thirty-two taxa were measured at greater than 1 % abundance in at least one sample, ten of which differed significantly between the baseline healthy and FC groups. Specifically, Bacteroidales and <i>Roseburia</i> spp. were significantly more abundant (<i>P</i> < 0·05) in the healthy group and taxa including Ruminococcaceae, <i>Dorea</i> spp. and <i>Akkermansia</i> spp. were significantly more abundant (<i>P</i> < 0·05) in the FC group. In the FC group, <i>Faecalibacterium prausnitzii</i> abundance significantly increased (<i>P</i> = 0·024) from 3·4 to 7·0 % following Livaux™ supplementation, with eight of the nine participants showing a net increase. Lower proportions of <i>F. prausnitzii</i> are often associated with gastrointestinal disorders. The discovery that Livaux™ supplementation increased <i>F. prausnitzii</i> abundance offers a potential strategy for improving gut microbiota composition, as <i>F. prausnitzii</i> is a butyrate producer and has also been shown to exert anti-inflammatory effects in many studies.