Screening, structural characterization and anti-adipogenesis effect of a water-soluble polysaccharide from Lycium barbarum L. by an activity-oriented approach

This study aimed to describe the structural features and anti-adipogenesis effect of polysaccharides obtained from Lycium barbarum L. by a bioactivity-oriented purification method. First, crude polysaccharide LICP009 was identified as the main bioactive compound with potential inhibition of intracellular lipid accumulation. Bioactivity guided fractionation was further performed using ion-exchange chromatography and Sephadex G-50 to obtain the purified component LICP009-2-1. This component was mainly composed of arabinose (Ara), galactose (Gal), glucose (Glc), galacturonic acid (GalA), and glucuronic acid (GlcA) in a molar ratio of 40.2:31.5:4.2:5.8:5.7 with a molecular weight of 1.35 × 104 g/mol. Linkage and NMR data indicated that the backbone of LICP009-2-1 was consisted of a repeated unit of →3,6)-β-D-Galp-(1→ residues, with three branches composed of α-L-Araf-(1→, α-L-Araf-(1 → 5)-α-L-Araf-(1 → 5)-α-L-Araf-(1 → 3)-β-D-Galp-(1→, and α-L-Araf-(1 → 2)-α-L-Araf-(1→[4)-β-D-Galp-(1]3 → . In differentiated 3T3-L1 adipocyte model, LICP009-2-1 exhibited an antiadipogenic effect by decreasing lipid accumulation, as well as downregulating the expression of key transcription factors and proteins in the adipogenesis pathway in a dose-dependent manner. In high-fat-diet-induced obese mice, oral administration of LICP009-2-1 counteracted the progression of obesity and hyperlipidemia. These results indicated that LICP009-2-1 plays anti-adipogenic and anti-obesity roles both in vitro and in vivo, and could be an anti-obesity agent utilized as medicinal, pharmacological and functional food ingredient.