Generation of structurally diverse pectin oligosaccharides having prebiotic attributes

Pectin oligosaccharides (POSs) are being recognized as potent prebiotics, given their structural complexity. Here, POSs were generated from apple pectin, rhamnogalacturonan-I and homogalacturonan with different degrees of esterification (high and low) using an optimized concentration of trifluoroacetic acid. The resulting POSs were analytically characterized, revealing that they contain linear and branched oligomers with a degree of polymerization (DP) up to 7. Biological activity of the generated POSs was determined in terms of immuno- and bacterio-modulatory perspectives. POSs significantly reduced the inflammatory response triggered by lipopolysaccharide and promoted the growth of several bacteria beneficial to the human gut. Overall results indicate that the degree of esterification of POSs is not a key element, but length of the DP and structure of POSs are responsible for biological outcomes. Owing to their biological activity, the POSs generated here can be considered as effective prebiotics and can be exploited for maintaining immune and microbial homeostasis in the human gut.