Abstract

A method to produce low molecular weight saturated oligogalacturonides (OGalAs) was developed. Among the two commercial pectinases evaluated (Pectinex Yielmash and Biopectinase), Pectinex Yielmash was selected due to its superior OGalAs yield and a higher OGalAs/galacturonic acid (GalA) ratio. Polygalacturonic acid (PGalA), as well as low methoxyl (LM) and high methoxyl (HM) pectins, were subjected to ultrasound (US) pretreatment followed by enzymatic hydrolysis. The US pretreatment was applied at varying intensities ranging from 0.5 to 8 W mL(-1). Optimal OGalAs yields (similar to 100 %) were achieved at 2.5 and 4 W mL(-1) for PGalA and LM pectin, respectively, whereas a maximum yield of 60.49 % was obtained from HM pectin at 8 W mL(-1). Additionally, PGalA solutions (2 %-8 %) were pretreated using either US (2.5 W mL(-1)) or hydrothermal (HT) conditions (145 degrees C for 35 min). While US treatment released both GalA and OGalAs, HT pretreatment resulted exclusively in GalA release. Liquid chromatography quadrupole time of flight mass spectrometry (LC-QToF MS) analysis revealed that the OGalAs generated from PGalA, LM, and HM pectins consisted of di and tri galacturonic acid units. Moreover, OGalAs from both LM and HM pectins exhibited methylated derivatives. OGalAs are increasingly valued for their diverse health benefits and prebiotic potential, as well as their role as plant defense elicitors. The proposed method offers a promising and versatile alternative for their efficient production.