Gut enterotypes are stable during Bifidobacterium and Lactobacillus probiotic supplementation.

The human gut microbiome has been classified into three distinct enterotypes (Bacteroides, Prevotella, and Ruminococcus). The relationship between probiotics and gut enterotype is not yet clear. Cayenne pepper is effective in vitro as a prebiotic for Bifidobacteria and Lactobacilli, so cayenne ingestion with probiotics may lead to more profound gut microbial shifts. We aimed to determine whether probiotics (with or without cayenne pepper) alter gut bacterial community composition and if these changes are associated with the original gut enterotype of the individual. A total of 27 adult participants provided three fecal samples: prior to probiotic treatment (baseline), post probiotic treatment (probiotic), and post probiotic plus cayenne pepper treatment (probiotic + cayenne). DNA was extracted, amplified, and the V4 region sequenced on the Illumina MiSeq platform using V2 chemistry. Sequence reads were processed in mothur and assigned using the SILVA reference by phylotype. Three enterotypes characterized the study population-Bacteroides (B; n = 6), Prevotella (P; n = 11), and Ruminoccocus (R; n = 10). There was no significant increase in probiotic genera in fecal samples after treatment periods. Alpha diversity scores were significantly lower in B-type but not in P- or R-type individuals after probiotic treatment. For the majority of individuals, their enterotype remained constant regardless of probiotic (and cayenne) treatment. This suggests that baseline gut community characteristics and enterotype classification influence responsiveness to probiotic treatment, but that enterotype is stable across administration of prebiotic and probiotics. PRACTICAL APPLICATION: A person's gut microbial community influences their responsiveness to probiotics and prebiotic ingredients. Consumers must understand that it is difficult to shift their gut microbiota even with simultaneous administration of prebiotic and probiotic. Greater understanding of these phenomena will enable consumers to choose the most efficacious products for their needs.