Impact of a jelly containing short-chain fructo-oligosaccharides and Sideritis euboea extract on human faecal microbiota

In this randomized, double-blinded, placebo-controlled clinical study we aimed to evaluate the in vivo prebiotic effects of a functional food containing short-chain fructo-oligosaccharides (sc-FOS) and Sideritis euboea extract on human faecal microflora. Sixty-four healthy volunteers 26 men and 38 women (age range: 22–51) were assigned to consume daily a jelly containing 5 g sc-FOS and 0.3 g S.euboea extract or a placebo for 30 d. Stool samples were collected prior to the study on day 15 and 30 of intervention and 2 weeks after. Enumeration of faecal bacteria was performed by plate count techniques. Gastrointestinal side effects were recorded during the treatment period. Data demonstrated a significant bifidogenic effect of the experimental jelly compared to the placebo after 15 [9.54 ± 0.83 vs. 8.57 ± 1.91 log10CFU (colony forming units)/g faeces P = 0.001] and 30 d of consumption (9.34 ± 1.04 vs. 8.57 ± 1.98 log10CFU/g faeces P = 0.027) and significant higher bifidobacterial levels in the sc-FOS + extract group 2 weeks after the end of intervention (9.33 ± 0.61 vs. 8.79 ± 0.93 log10CFU/g faeces P = 0.015). A trend for greater flatulence was detected after 15 d of functional food ingestion with no further differences in gastrointestinal symptoms. In conclusion the daily intake of a jelly containing sc-FOS and S.euboea extract is well-tolerated and demonstrated significant bifidogenic properties in healthy volunteers consuming their usual diets.