Pectinase hydrolysis of Dendrobium huoshanense polysaccharide and its effect on protein nonenzymatic glycation

• Published in: International journal of biological macromolecules Vol. 61; pp. 439 - 447
• Main Authors: Zha, Xue-Qiang, Li, Xiao-Long, Zhang, Hai-Lin, Cui, Shao-Hua, Liu, Jian, Wang, Jun-Hui, Pan, Li-Hua, Luo, Jian-Ping
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.10.2013
• Subjects: arabinose; Dendrobium; Dendrobium - chemistry; Dendrobium - metabolism; Dendrobium huoshanense polysaccharide; Enzymatic degradation; galactose; glucose; glycation; Hydrogen-Ion Concentration; Hydrolysis; infrared spectroscopy; Kinetics; mannose; Models, Chemical; Molecular Weight; Monosaccharides - chemistry; Nonenzymatic glycation of proteins; Plant Extracts - chemistry; Plant Proteins - chemistry; Plant Proteins - metabolism; polygalacturonase; Polygalacturonase - chemistry; polysaccharides; Polysaccharides - chemistry; Proteolysis; reducing sugars; Reproducibility of Results; response surface methodology; Spectroscopy, Fourier Transform Infrared; Temperature; xylose; Nonenzymatic glycation of proteins; Dendrobium huoshanense polysaccharide; Enzymatic degradation
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2013.08.008

•An active polysaccharide (DHPD1) was isolated from Dendrobium huoshanense.•Enzymatic hydrolysis conditions for DHPD1 degradation were optimized.•Molecular weights of DHPD1 and DHPD1-derived fragments (DDF) were determined.•Monosaccharide composition and structural feature of DHPD1 and DDF were tested.•The inhibitory effects of DHPD1 and DDF on nonenzymatic glycation were measured. The aim of this study was to investigate the inhibitory effects of molecular weight alteration of Dendrobium huoshanense polysaccharide on protein nonenzymatic glycation. For this purpose, one homogeneous active polysaccharide DHPD1 with molecular weight 3.2kDa was extracted from D. huoshanense. GC analysis showed that DHPD1 was mainly composed of glucose, arabinose, galactose in a molar ratio of 0.023:1.023:0.021 with a trace of mannose and xylose. In order to get DHPD1-derived fragments with different molecular weight, response surface methodology was employed to optimize the enzymatic degradation conditions. The maximum reducing sugar production (0.399mg/mL) was obtained under an optimal condition including pectinase dosage 126U/mL, reaction pH 4.46 and reaction temperature 48°C. By applying this condition, three DHPD1-derived fragments with different molecular weights were obtained through changing the hydrolysis time. Infrared spectroscopy analysis indicated that the backbone structure of DHPD1 was not destroyed by pectinase hydrolysis. Monosaccharide composition analysis showed that pectinase preferred to liberate glucose from DHPD1. The inhibitory action of DHPD1 on protein nonenzymatic glycation reduced with the decrease of molecular weight.