A novel polysaccharide of Citrus medica L. var. sarcodactylis Swingle: purification, structural characterization, and hypolipidemic effects

Fingered citron ( Citrus medica L. var. sarcodactylis Swingle) is an edible fruit with great potential in functional food. In this study, we isolated and purified a novel polysaccharide from fingered citron, designated as ZFP2, and investigated its structural characteristics and in vitro hypolipidemic activity. ZFP2 was found to be composed of arabinose (Ara), galactose (Gal), and galacturonic acid (GalA) in a molar ratio of 2.61:2.27:14.39, with an average molecular weight of 407 kDa. The majorly backbone of ZFP2 is composed of 1,4-GalpA, 1,2,4-Rhap, 1,5-Araf, 1,6-Galp and 1,3,6-Galp. ZFP2 exhibited a semi-crystalline structure and irregular plate-like morphology. In an oleic acid (OA)-induced lipid overload model using human liver cancer cells (HepG2), ZFP2 significantly reduced intracellular lipid accumulation and improved lipid profiles. Mechanistic studies demonstrated that ZFP2 modulates lipid metabolism through the PPARα/LXRα/ABCG8 signaling pathway, enhancing lipid catabolism and reducing lipid accumulation. These findings underscore the potential of ZFP2 as a natural hypolipidemic agent and support the development of fingered citron polysaccharide as functional food ingredients for managing lipid-related disorders. • A novel polysaccharide (ZFP2) was isolated from Citrus medica L. var. sarcodactylis Swingle. • The structure of ZFP2 was characterized. • ZFP2 alleviated cellular lipid accumulation and mitigated oxidative stress. • ZFP2 modulated the expression of key genes within pathways associated with lipid metabolism.