Structural characterization of chia seed polysaccharides and evaluation of its immunomodulatory and antioxidant activities

Zhijun Xiao; Changyang Yan; Chunxue Jia; Ying Li; Yuanlin Li; Jie Li; Xinxin Yang; Xueyan Zhan; Changhua Ma

doi:10.1016/j.fochx.2023.101011

Structural characterization of chia seed polysaccharides and evaluation of its immunomodulatory and antioxidant activities

Food Chem X. 2023 Nov 17:20:101011. doi: 10.1016/j.fochx.2023.101011. eCollection 2023 Dec 30.

Authors

Zhijun Xiao¹, Changyang Yan¹, Chunxue Jia¹, Ying Li², Yuanlin Li¹, Jie Li¹, Xinxin Yang¹, Xueyan Zhan¹, Changhua Ma¹

Affiliations

¹ School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 100029, China.
² Department of Pharmacy, The First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and Technology, Luoyang 471003, China.

Abstract

This study aims to extract an active heteropolysaccharide Chia seed polysaccharide (CSP-A) and further purified by DEAE Sepharose Fast Flow and Sepharose CL-6B chromatographic column, characterize its structure, and evaluate its antioxidant and immunomodulatory activities. Structural analysis revealed that CSP-A was composed of d-mannose, d-glucuronic acid and d-xylose in a molar ratio of 1:3:4 with molecular weight of 1.688 × 10⁵ Da, owning 4 sugar residues of β-d-Manp-(1→, →4)-α-d-GlcpA-(1→, →2,4)-β-d-Xylp-(1→, and → 4)-β-d-Manp-(1 →. Congo red assay and microscopic characteristics showed that CSP-A in its solution may possess a helical conformation. In vitro experiments showed that CSP-A had moderate DPPH· and OH· scavenging activities. CSP-A also enhanced the phagocytosis ability of RAW 264.7 cells and prompted the release of NO, TNF-α, IL-6 and IL-1β from RAW 264.7 cells, which indicated CSP-A had immune regulation effect. This experiment provides scientific basis for further utilization and development of chia seeds, a kind of functional food.

Keywords: Antioxidants; Chia seeds polysaccharide; Functional food; Homogeneous polysaccharide; Immunomodulatory activity; Structure characterization.