Prebiotic effects of pectooligosaccharides obtained from lemon peels on the microbiota from elderly using an in vitro continuous colon model (TIM-2)
The development of new prebiotics capable to modulate the gut microbiota in the elderly has become an area of great interest due to the particular vulnerability and frailty of this population. In the present work, mixtures of pectin-derived oligosaccharides (POS) were manufactured from lemon peel wastes and evaluated for their capability for modulating the gut microbiota using, as inoculum, a pool of faeces from elderly donors. Both changes on the microbiota and on the metabolic activity were assessed and compared to commercial fructooligosaccharides (FOS) and the standard ileal efflux medium (SIEM) using the TIM-2 in vitro colon model. POS fermentation led to similar or even better effects than FOS at phylum, family and genus level. Higher increments in beneficial species such as Faecalibacterium prausnitzii and larger alpha diversity values were observed with POS in comparison with FOS and in some cases with SIEM. The PCoA analyses revealed that the microbial profiles resulting from POS and FOS bacterial fermentation were rather similar and differed from those observed after SIEM fermentation. Finally, although butyrate cumulative productions were comparable among substrates, the highest short chain fatty acids (SCFA) and the lowest branched chain fatty acids (BCFA) cumulative productions were observed in POS experiments. These results support the potential of pectin-derived oligosaccharides as prebiotic candidates targeting elderly gut health.