Title
Sulfation of birch wood xylan with sulfamic acid in the presence of activators: experiment and theory
Authors
АLEKSANDR S. KAZACHENKO, FERIDE AKMAN, YAROSLAVA D. BEREZHNAYA, NATALYA VASILIEVA, OLGA YU. FETISOVA, NOUREDDINE ISSAOUI, ZHOUYANG XIANG, ANNA S. KAZACHENKO, TIMUR IVANENKO, SVETLANA NOVIKOVA, OMAR M. AL-DOSSARY and LEDA G. BOUSIAKOU

Received July 4, 2023
Published Volume 57 Issue 9-10 September-December
Keywords xylan, xylan sulfate, sulfamic acid, birch, density functional theory

Abstract
Xylan is a polysaccharide found in plant cell walls. It is considered to be a biodegradable polymer, which does not affect negatively the environment. Sulfated xylan derivatives exhibit valuable bioactive properties, in particular, anticoagulant and hypolipidemic. We report on the development of a new method for sulfation of birch wood xylan. Activators of the sulfation reaction with sulfamic acid have been evaluated. Numerical methods have been used to establish the optimum process parameters that ensure the maximum sulfur content in the reaction product. The incorporation of a sulfate group has been confirmed by infrared and nuclear magnetic resonance spectroscopy, and elemental analysis. The initial and sulfated xylans have been comprehensively studied by theoretical methods and the most favorable conformations of the initial xylan and its sulfate have been established.