Production of saturated and Δ4,5-unsaturated oligogalacturonides from differently methylated pectins and evaluation of their prebiotic activity

Campos D.; Sánchez J.; Aguilar-Galvez A.; Carrasco L.; Portales R.; Chirinos R.; Terán-Hilares F.; Pedreschi R. · Food Bioscience (2026) · DOI: 10.1016/j.fbio.2026.108798

Resumen

AbstractThis study investigated the enzymatic modification of pectin into structurally distinct including saturated, unsaturated, and saturated/methylated forms (SOGals, UMOGals, and S/MOGals) using polygalacturonase and pectin lyase on substrates with different degrees of methylation. High- and low-methoxyl pectins showed DM values of 68.56% and 36.97%, respectively, while polygalacturonic acid was non-esterified. Lower DM was associated with higher galacturonic acid content, and the presence of neutral sugars indicated the existence of rhamnogalacturonan regions and other cell wall components. Enzymatic treatments generated distinct oligogalacturonides. PG hydrolysis of PGalA produced SOGals (DP 1–4), whereas combined PG and PL treatment of LM pectin yielded SOGals and partially methyl-esterified oligomers (S/MOGals, DP 1–4). In contrast, PL hydrolysis of HM pectin generated Δ4,5-unsaturated methylated oligogalacturonides (UMOGals, DP 3–6). HILIC–QToF MS confirmed their structures and revealed positional isomers associated with heterogeneous methylation patterns. Fermentation assays with Lactobacillus rhamnosus, Lactobacillus plantarum, and Bifidobacterium bifidum showed that substrate structure strongly influenced microbial growth and metabolic outputs. Oligogalacturonides promoted higher growth rates than their parent polysaccharides, particularly UMOGals and S/MOGals. Overall, DP, DM, and structural unsaturation were key determinants of fermentability and prebiotic potential, supporting enzymatic pectin depolymerization as a strategy to produce tailored oligogalacturonides with potential functional and biological applications.

Instituciones: Universidad Nacional Agraria La Molina; Universidad Nacional Autónoma Altoandina de Tarma