Author(s): Silva, Marcos Fellipe da ; Colunga, Alondra ; Batista, José Josenildo ; Pereira, Catarina ; Nobre, Clarisse ; Teixeira, J. A. ; Coelho, Rosana Goldbeck
Date: 2024
Persistent ID: https://hdl.handle.net/1822/98431
Origin: RepositóriUM - Universidade do Minho
Subject(s): Lignocellulosic wastes; Prebiotic Oligosaccharides; Gut microbiota
Agro-industrial residues, typically viewed as a low-value by-product, have demonstrated significant potential to produce prebiotic oligosaccharides, such as xylo-oligosaccharides (XOS) and cello-oligosaccharides (COS). This study evaluates the effects of XOS and COS, derived from sugarcane bagasse (SB) and corn hulls (CH) through enzymatic hydrolysis, on the modulation of human intestinal microbiota in vitro. SB and CH were pretreated with an alkaline solution (5% KOH, 121 °C, 1 atm, 15 min), followed by enzymatic hydrolysis (pH 5.0, 50 °C, 2% solids, 200 rpm) using Shearzyme and Celluclast enzymes for 48 h, producing XOS and COS. The hydrolysates were then fermented in vitro (37 °C, 48 h) with fecal microbiota from five healthy volunteers. Genomic DNA was extracted, and microbial communities were analyzed via Illumina 16S rRNA sequencing. Optimal XOS yields were achieved within 48 h, with concentrations of 7.47 g/L SB and 4.41 g/L CH, while COS production reached 0.27 g/L for SB and 0.46 g/L for CH. During the initial 12 h of fermentation, a rapid increase in optical density and a decrease in pH were observed. COS notably increased Actinobacteria and while XOS promoted Firmicutes and Bacteroidota. Fermentation of COS and XOS from SB and CH selectively modulated the human gut microbiota, increasing beneficial genera such as Bifidobacterium (with COS being the main one), Blautia, Slackia, Collinsela and, Bacteroides, which are vital for metabolic health, immune modulation and fiber digestion. Notably, COS produced more short-chain fatty acids (SCFAs) with concentrations of 22.33 g/L and 24.39 g/L for SB and CH, versus 7.62 and 15.82 g/L in COS from SB and CH. SCFAs play critical roles in reducing intestinal pH, supporting metabolic health, immune response and inhibiting pathogens. Thus, XOS and COS obtained promising potential as nutraceutical ingredients for positive human gut microbiota modulation.
