Exploring the modulatory effect of trehalose-derived galactooligosaccharides on key gut microbiota groups

Trehalose (α-d-glucopyranosyl-(1-1)-α-D-glucopyranoside) has found applications in diverse food products as a sweetener, stabilizer, and humectant. Recent attention has focused on trehalose due to its contradictory effects on the virulence of Clostridium difficile. In this study, we investigate the impact of novel trehalose-derived galactooligosaccharides (Treh-GOS) on the human gut microbiota using in vitro fecal fermentation models. Distinct Treh-GOS structures elicit varying taxonomic responses. For instance, β-Gal-(1-4)-trehalose [DP3(1-4)] leads to an increase of Bifidobacterium, comparable to results observed with commercial GOS. Conversely, β-Gal-(1-6)-trehalose [DP3(1-6)] prompts an increase in Lactobacillus. Notably, both of these trisaccharides yield the highest concentrations of butyric acid across all samples. On the other hand, Treh-GOS tetrasaccharide mixture (DP4), featuring a novel trehalose galactosylation in both glucose units, fosters the growth of Parabacteroides. Our findings underscore the capacity of novel Treh-GOS to modulate the human gut microbiota. Consequently, these innovative galactooligosaccharides emerge as promising candidates for novel prebiotic applications.