Anti-inflammatory activities of polysaccharides isolated from Aloe saponaria Haw grown in Namhae

Abstract

To identify the physiological activity of Saponaria aloe cultivated in the Namhae-gun, polysaccharides, as the main physiologically active substances, were isolated and their antioxidant and anti-inflammatory activities were confirmed. Hot-air dried saponaria were extracted with hot water (80°C, 24 h) and then the extracts were freeze dried (HWE). HWE was dialyzed using 3.5 kDa dialysis membrane and only intra-dialysis solution was taken and freeze dried (IDS) for experiment. Total polysaccharide content was higher in IDS (195.32 mg/g) than HWE however, anthraquinone content was lower in IDS. Total phenolic compounds (TPC) contents of HWE and IDS were 594.04 and 1,047.23 mg/100 g, respectively. The IC50 values of 2,2-Azinobis-(3-ethylbenzo-thiazoline-6-sulphonate (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities were higher 1.7 and 1.8 folds in HWE than IDS, respectively. The MTT assay showed that the sample concentrations below than 100 μg/mL were sufficient to exert anti-inflammatory activity in lipopolysaccharide (LPS) induced RAW 264.7 cells. The production levels of nitric oxide (NO) and reactive oxygen species (ROS) were significantly decreased in 100 μg/mL of HWE (p⟨0.01) and IDS (p⟨0.001) treated group than those in LPS only treated group. The expression levels of tumor necrosis faction (TNF)-α and interleukin (IL)-6 were significantly lower in all treated samples than in the LPS only treated group. However, there was no significant difference between the HWE and IDS-treated group. The expression activity of IL-1β was no significant difference among all samples.