Isolation, Characterization and Antitumor Effect on DU145 Cells of a Main Polysaccharide in Pollen of Chinese Wolfberry

Modern studies have shown that pollen has a certain role in the treatment of prostate-related diseases. In the present study, pollen polysaccharides from Chinese wolfberry (WPPs) were extracted by hot-water extraction and ethanol precipitation, further purified by chromatography on a DEAE-cellulose column and Sephadex G-100 column. Homogeneous polysaccharide CF1 of WPPS was obtained, the molecular weight of which was estimated to be 1540.10 +/- 48.78 kDa by HPGPC-ELSD. HPLC with PMP derivatization analysis indicated that the monosaccharide compositions of CF1 were mannose, glucuronic acid, galacturonic acid, xylose, galactose, arabinose, and trehalose, in a molar ratio of 0.68: 0.59: 0.27: 0.24: 0.22: 0.67: 0.08. The antitumor effects of CF1 upon MTT, Tunel assay and flow cytometry assay were investigated in vitro. The results showed that CF1 exhibited a dose-dependent antiproliferative effect, with an IC50 value of 374.1 mu g/mL against DU145 prostate cancer cells. Tunel assay and flow cytometry assay showed that the antitumor activity of CF1 was related to apoptosis in vitro. The present study suggested that the CF1 of WPPs might be a potential source of antitumor functional food or agent.