The xylose-rich pectins from pea hulls

Abstract

The hot acid extract of pea hull, HSP, was rich in galacturonic acid, arabinose and xylose. It was fractionated by copper precipitation followed by ion-exchange chromatography. The copper-soluble fraction represented 26% of HSP and was mostly composed of an arabinan with a low degree of branching, some heteroxylans and a glucan, probably starch. The copper-precipitate (74% of HSP) contained pectins and some residual arabinan, xylan, glucan and mannan. One of the pectic fractions was rich in terminal xylose and fucose; it could be partially degraded by endo-polygalacturonase but not by endo-xylanase and seemed to contain xylogalacturonans.