Characterization of Moringa oleifera roots polysaccharide MRP-1 with anti-inflammatory effect

Moringa oleifera is a mutli-purpose herbal plant which has attained enormous attention as a natural source of nutrients and folk medicine. This work aimed to get a novel polysaccharide, termed MRP-1, which was isolated from Moringa oleifera roots with hot water extraction method followed by ethanol precipitation and purified with DEAE-Sepharose Fast Flow column. Monosaccharide composition analysis based on GC-MS showed that MRP-1 mainly consisted of Rha, Ara, Fru, Xyl, Man and Gal in the molar ratio of 1.5:2.0:3.1:6.0:5.3:1.1. The Roman spectra, FT-IR and NMR analysis showed that the typical features of carbohydrates, such as α-Araf, α-Gly, β-Galp, α-GalpA and β-Gly was contained by MRP-1. The LPS-induced RAW264.7 macrophage cells were used to evaluate the anti-inflammatory activity of MRP-1. The result demonstrated that the increasing of NO and TNF-α production induced by LPS could be prevented by different concentrations of MRP-1 treatment. Moreover, the mRNA expression level of iNOS induced by LPS was decreased significantly (p < 0.05) by MRP-1 treatment while show no obvious effect on the COX-2 mRNA expression. This study may provide new possible application of Moringa oleifera root polysaccharide related to anti-inflammation.