ANOTHER APPROACH TO PECTIN BLOCKINESS - USE OF PARTIAL POLYGALACTURONASE DIGESTION

摘要

This document describes a semi-quantitative method for the determination of the length of blocks of contiguous unesterified hexose moieties in pectin. The method comprises exposing aliquots of a pectin sample to endo-polygalacturonase so a series with very slightly treated samples as well as more severely treated samples is produced. The block-length is then estimated by comparing the ensuing loss of molecular weight either to the production of non-polymeric degradation product, or to the increase in apparent degree of esterification of the part that remains polymeric. The length of blocks in the investigated pectin samples seems in some cases to be at least about one tenth of the average length of molecules.