Structure of KOH-extractable polysaccharides of tree greenery of from Siberian fir Abies sibirica Ledeb

Evgeny G Shakhmatov; Elena N Makarova

doi:10.1016/j.carbpol.2021.118794

Structure of KOH-extractable polysaccharides of tree greenery of from Siberian fir Abies sibirica Ledeb

Carbohydr Polym. 2022 Jan 15:276:118794. doi: 10.1016/j.carbpol.2021.118794. Epub 2021 Oct 20.

Authors

Evgeny G Shakhmatov¹, Elena N Makarova²

Affiliations

¹ Institute of Chemistry, Federal Research Center "Komi Science Center of the Ural Branch of the Russian Academy of Sciences", Pervomaiskaya St. 48, Syktyvkar 167982, Russia.
² Institute of Chemistry, Federal Research Center "Komi Science Center of the Ural Branch of the Russian Academy of Sciences", Pervomaiskaya St. 48, Syktyvkar 167982, Russia. Electronic address: makarowa.elena-ma@yandex.ru.

PMID: 34823801
DOI: 10.1016/j.carbpol.2021.118794

Abstract

Polysaccharide AS_K was extracted with aqueous KOH from the Abies sibirica foliage. Pectin, xylan, AGPs and xyloglucan were isolated from AS_K by anion-exchange chromatography and Smith degradation, combined with enzymatic cleavage. Potential interactions between those polymers were examined. Since xylan, AGPs, RG-I and glucan were co-fractionated following complete removal of galacturonan (HG) with polygalacturonase, it can be inferred that the enzymatic cleavage of HG did not affect co-fractionation of cross-linking glycans, RG-I and AGPs. These were hypothesized to be bound via a covalent cross-link, as the removal of HG regions did not affect this complex. Given that pectin was represented solely by RG-I regions, it can be assumed that some of glucan, xylan and AGPs were associated directly with RG-I. Besides, the enzymatic hydrolysis eliminated most of xylose and rhamnose. This suggests implicitly that some of xylan was linked to RG-I.

Keywords: Abies sibirica; Arabinoglucuronoxylan; NMR; Pectic polysaccharides; Structure; Xyloglucan.