Fermentation properties and prebiotic potential of different pectins and their corresponding enzymatic hydrolysates

Pectin can be utilized to modulate the host gut microbiomes. In this study, the fermentability of pectins and their enzymatic-hydrolysates from different sources (sunflower stalks pith, apple, orange, hawthorn and okra) by pig faecal microbiota in vitro were compared. The changes in pH, Mw, total carbohydrate content, gut microbiota, SCFAs production along the fermentation duration for each sample and their differences among distinct pectins were investigated. The results showed that all pectins and their corresponding oligomers were highly fermentable and promoted the production of health-promoting SCFAs. As low-specificity fibers, oligomeric pectins can be utilized extensively by more gut microbiota, and selectively enriched classical bifidogenic effects. Compared to the more common homogalacturonan-rich pectins from sunflower stalks pith, apple, orange, and hawthorn, the okra pectin with a unique rhamnogalacturonan-I branched structure exhibited higher prebiotics potential, as evidenced by the highest level in SCFAs-producing bacteria and beneficial SCFAs molecules, along with the lower relative abundance of pathogenic bacteria. This study highlighted the targeted manipulation of the gut microbiome by pectin, promoting the establishment of structure-directed-microbiota relationships and the development of microbiome-based personalized nutrition.