Structural characterisation of a novel polysaccharide from <i>pseudostellaria heterophylla</i> fibrous root and its anti-inflammatory and antioxidant activities <i>in vitro</i>

A novel water-soluble polysaccharide, named PF90-1, with a molecular weight of 1.8 kDa, was isolated and purified from the fibrous root of <i>Pseudostellaria heterophylla</i>. PF90-1 is composed of Gal, Glc and Man in a molar ratio of 73.61: 19.11: 7.28. Methylation analysis revealed that PF90-1 comprises of T-Gal<i>p</i>, 1,4-Gal<i>p</i>, 1,3,4-Gal<i>p</i>, 1,2,3,4-Gal<i>p</i>, T-Glc<i>p</i> and 1,3-Man<i>p</i> in a molar ratio of 37.89: 9.37: 17.01: 12.01: 15.88: 7.83. Bioactivity experiments showed that PF90-1 significantly improved lipopolysaccharide (LPS)-induced inflammatory damage in RAW264.7 cells by inhibiting nitric oxide (NO) production and reducing the levels of pro-inflammatory factors (IL-1β and TNF-α). In addition, PF90-1 exhibited strong antioxidant effects, protecting PC12 cells from H₂O₂-induced oxidative damage. This findings suggest that PF90-1 holds potential therapeutic value for the treatment of inflammatory and oxidative injuries.