Extraction, Structural Characterization and Anti-Inflammatory Activity of Polysaccharides From Conioselinum vaginatum

Polysaccharides are the key functional components in Conioselinum vaginatum. This study aims to optimize the extraction process of Conioselinum vaginatum polysaccharides (CVP), investigate their structural characteristics, and evaluate their anti-inflammatory activity. Through response surface methodology (RSM), the optimal extraction conditions were determined as follows: time 29 min, ultrasonic power 204 W, liquid-solid ratio 38:1 mL/g, and temperature 54°C. Under these conditions, the yield reached 10.12% ± 0.38%. CVP was separated and purified using a DEAE-650-M cellulose column and a Sephadex G-75 gel column, yielding two homogeneous polysaccharides, CVP-I and CVP-II. Their molecular weights (Mw) were 26.42 ± 0.37 and 17.81 ± 0.23 kDa, respectively. Both polysaccharides were composed of varying proportions of fucose, rhamnose, arabinose, mannose, and glucose, and simultaneously contained α- and β-glycosidic bonds alongside pyranose and furanose ring structures. The backbone of CVP-I primarily consists of →4)-Fucp-(1 → and →2,4)-Rhap-(1→, with terminal residues mainly being T-Araf. In contrast, CVP-II is mainly composed of →2,4)-Rhap-(1 → and →4)-Glcp-(1→, with terminal residues primarily T-Fucp and T-Araf. Additionally, they exhibited different chemical compositions, stable triple-helix conformations, low crystallinity, unique morphological characteristics, uniform particle size distribution, and excellent thermal stability. Anti-inflammatory activity studies revealed that both CVP-I and CVP-II effectively regulated the production of nitric oxide (NO), prostaglandin E2 (PGE₂), interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) in LPS-induced RAW264.7 macrophages, thereby inhibiting the occurrence of inflammation. These findings suggest that CVP-I and CVP-II hold potential applications in the fields of functional foods and pharmaceuticals.