A natural anti-obesity reagent derived from sea buckthorn polysaccharides: Structure characterization and anti-obesity evaluation in vivo

Sea buckthorn polysaccharide (SBP) has received increasing attention for its various bioactive functions. In this study, a novel polysaccharide SBP-1 was initially separated from crude SBP and further purified to obtain its main fraction SBP-1-A with a Mw of 9944 Da, consisting of Rha, Ara, Gal, Glc, and GalA. The structure of SBP-1-A was characterized based on FT-IR, GC-MS, and 1D/2D NMR, and its backbone was composed of a repeated unit of → 3,4)-β-l-Rhap-(1 → 4)-α-d-GalAp-(1 → 4)-α-d-GalAp-(1 → with branches at C-4 position comprised of α-l-Araf, β-d-Galp, β-d-Glcp, α-d-Glcp. Besides, the anti-obesity effects of SBP-1 on high-fat diet mice were evaluated, indicating it could restrain the body weight gain and lipids accumulation by promoting the expression of PGC1α, UCP-1, and PRDM16 to activate the brown adipocyte and improve the thermogenesis. In summary, the results offered new supports for the structural information of SBP and its feasibility to be used as a natural anti-obesity reagent.