Isolation, purification and structure characteristics of polysaccharide from Scutellaria barbata

Four water-soluble polysaccharides named as SBP-11, SBP-12, SBP-13 and SBP-14 were obtained from Scutellaria barbata by defatting, boiling water extraction, deproteinating, decoloration and DEAE-52 chromatography purificaton. The carbohydrate content of SBP-11, SBP-12, SBP-13 and SBP-14 were 90.24%, 88.56%, 86.42% and 85.23%, respectively. SBP11 with molecular weight (MW) 1.8×10⁴ D was composed of rhamnose, fucose, arabinose, glucose and galactose with a molar ratio of 1:0.21:0.38:0.52:0.78. SBP-12 with MW 6.5×10⁴ D was composed of rhamnose, arabinose, glucose and galactose with a molar ratio of 0.71:0.81:1:0.91. SBP-13 with MW 6.4×10⁵ D was composed of unknown component, rhamnose, fucose, glucose and galactose with a molar ratio of 0.14:0.31:0.28:0.21:1. SBP-14 with MW 1.0×10⁶ D was composed of rhamnose, fucose, glucose and galactose with a molar ratio of 1:0.15:0.24:0.96.