Structural characterization and bioactivity evaluation of water-extractable polysaccharides from chickpeas (Cicer arietinum L.) seeds

Yingying Zhu; Baoqing Dun; Zhenxing Shi; Yuanji Wang; Li Wu; Yang Yao

doi:10.3389/fnut.2022.946736

Structural characterization and bioactivity evaluation of water-extractable polysaccharides from chickpeas (Cicer arietinum L.) seeds

Front Nutr. 2022 Jul 28:9:946736. doi: 10.3389/fnut.2022.946736. eCollection 2022.

Authors

Yingying Zhu^{1

2}, Baoqing Dun¹, Zhenxing Shi^{1

3}, Yuanji Wang¹, Li Wu¹, Yang Yao¹

Affiliations

¹ Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China.
² Henan Key Laboratory of Cold Chain Food Quality and Safety Control, College of Food and Bioengineering, Zhengzhou University of Light Industry, Zhengzhou, China.
³ School of Food Science and Technology, Henan University of Technology, Zhengzhou, China.

Abstract

Two water-extractable polysaccharide fractions designated as CWP (7. 37 × 10⁵ Da) and CWP-0.2 (1.58 × 10⁴ Da) were isolated and purified from chickpea (Cicer arietinum L.) seeds. The chemical structure of the two polysaccharides was characterized by various methods. Monosaccharide composition and methylation analysis showed that CWP was composed of Man and Glc in a molar ratio of 44.6:55.4, and CWP-0.2 was composed of Rha, Ara, Man, Glc, and Gal in a molar ratio of 10.6:23.3:5.2:4.9:56. Further structural characterization indicated that the main chain connection of CWP was → (2-β-d-Fruf-1) n →, and the main chain connection of CWP-0.2 was explored as → 2,4)-α-l-Rhap-(1 → 3)-α-d-Galp-(1 → with the branched chain of → 2,4)-α-l-Rhap-(1 → o-4. Besides, both CWP and CWP-0.2 had antioxidant and immunoregulatory activity in vitro, through scavenging DPPH· and ABTS·⁺ as well as stimulating production of NO, IL-6, TNF-α and MCP-1 in RAW 264.7 macrophages. CWP-0.2 revealed significantly higher bioactivity than CWP.

Keywords: antioxidant; chemical structural; chickpea; immunoregulatory; polysaccharides.