Strucrual Analysis And Functioanl Properties Of A Polysaccharide From Seed Husks Of Plantago Asiatic L

Plantago asiatic L.belonging to the genus Plantago L.(Plantaginaceae)grows widely in China.A new polysaccharide was extractd,isolated and purified from the seed husks of Plantago asiatic L..Its strucrual characterization,thermal degradation property and in vitro biological activities were explored.Firstly,the crude polysaccharide from the seed husks of Plantago asiatic L.was obtained by organic solvent degreasing,alkaline extraction,deproteinization,decoloration and ethanol precipitation.Then DEAE-cellulose and Sephacryl S-400 column were applied to gain purified polysaccharide,which was named PMH with a purity of 98.9%.PMH has a molecular weigh of 1.4×10~6 Da determined by static light scattering.The thermal degradation property evaluation of PMH revealed a primary decomposition temperature range of 224.0-315.1oC during which 31.1%of PMH was decomposed.The apparent activation energy(Ea)of PMH was 173.1 kJ/mol.Secondly,structure analysis revealed that PMH consisted of a1,4-?-D-GalpA backbone with branches?-D-Galp-(3?1)-?-D-Galp-(3?1)-?-L-Araf and?-D-Galp-(2?1)-?-D-Galp-(2?1)-?-D-Xylp at the O-3position.One 1,2-?-L-Rhap was exsited every six1,4-?-D-GalpA with?-L-Rhap-(2?1)-?-D-Glcp-(4?1)-?-L-Araf at its O-3 position.Finally,the DPPH and hydroxyl radical scacenging capacities of PMH and Psyllium were similar,but PMH exhibited a significantly stronger peroxyl radical scavenging capacity than Psyllium.PMH also showed significant inhibitory activities on TNA-?,IL-1?,IL-6 and enhancement on IL-10 in the cultured RAW 264.7 mouse macrophage cells indicating potential anti-infammation activity.The mechanism might be partial through p38 MAPK/NF-?B signaling pathway.These results provided useful information for the relationship study between structure and activity on polysaccharide from seed husks of Plantago asiacitc L.The results from this research could be used to develop value-added utilization of Plantago L.and benefit local agricultural economy.