Structural characterization, α-amylase and α-glucosidase inhibitory activities of polysaccharides from wheat bran

• Published in: Food chemistry Vol. 341; no. Pt 1; p. 128218
• Main Authors: Lv, Qing-Qing, Cao, Juan-Juan, Liu, Rui, Chen, Han-Qing
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 30.03.2021; Elsevier
• Subjects: alpha-Amylases - metabolism; alpha-Glucosidases - metabolism; Dietary Fiber - analysis; Glycoside Hydrolase Inhibitors - chemistry; Glycoside Hydrolase Inhibitors - pharmacology; Molecular Weight; Polysaccharide; Polysaccharides - chemistry; Polysaccharides - pharmacology; Structural characterization; Wheat bran; α-Amylase; α-Glucosidase; α-Amylase; α-Glucosidase; Polysaccharide; Structural characterization; Wheat bran
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2020.128218

•Two polysaccharide fractions (WXA-1 and AXA-1) are obtained from wheat bran.•The compositions and structural characterizations of WXA-1 and AXA-1 are different.•AXA-1 exhibits stronger α-amylase and α-glucosidase inhibitory activities compared with WXA-1. In this study, two polysaccharide fractions were isolated from wheat bran by sequential extraction with water and alkaline solution, DEAE Cellulose-52 chromatography and Sephacryl S-400 gel permeation chromatography, they were named as WXA-1 and AXA-1, respectively. Structural analyses indicated that both polysaccharide fractions were heteropolysaccharides, their average molecular weights were 193 kDa and 107 kDa, respectively. The backbone of WXA-1 was → 4)-β-d-Xylp-(1→, which was substituted at O-3 positions by arabinose, glucose and galactose residues, while the backbone of AXA-1 was → 4)-β-d-Xylp-(1→, which was mainly substituted at O-3 positions by arabinose. AXA-1 exerted a stronger inhibitory effect on the activities of α-amylase and α-glucosidase compared with WXA-1. Moreover, AXA-1 exhibited a competitive inhibition of α-amylase and a mixed-type noncompetitive inhibition of α-glucosidase. These results suggest that AXA-1 can be used as α-amylase and α-glucosidase inhibitors.