Study On Structure And Apoptosis Inducing Activity Of Lycium Barbarum Polysaccharide

Based on the Lycium Barbarum. L as materials, study the extraction and purification process, composition and structure of Lycium barbarum polysaccharide, bioactivities of the Human Hepatocarcinoma Cells SMMC-7721 apoptosis induced.The best condition of alcohol precipitation was that added 80mL alcohol into the 50mL solution of Lycium Barbarum Polysaccharide, at room temperature for 12 hours, and repeated 5times. The best condition of decolorization was that LBP (0.2%, g/v): Chloroform:N-Butanol= 25:5:1 (v/v). The yield was 0.92 g/100g, conversion factor was 1.85. After the treatment of DEAE,6 components were gotten. LBP-4 and LBP-5 were purified by the Sephadex G-75, and were proved that they were pure Polysaccharides.The Mn of LBP-4 was 866130D and LBP-5 was 1412100D, tested by HPLC. The content of neutral sugar, galacturonic acid and protein of LBP-4 were 71.2%,16.0% and 2.1%. The content of neutral sugar, galacturonic acid and protein of LBP-5 were 67.3%, 23.2% and 3.1%. The gas chromatogram indicated that LBP-4 was composed of Fucose, Ribose, Rhamnose, Arabinose, Xylose, Glucose, Mannose, Galactose, and the mole ratio is 13.0:1.0:19.2:4.2:1.1:4.1:14.3:9.5; and LBP-5 was composed of Fucose, Rhamnose, Arabinose, Glucose, Mannose, Galactose, and the mole ratio is 3.2:5.1:1.0:20.5:2.0:26.4. LBP did not have the three helical structures, and the connection between sugar and protein was O-type. Experiments of Periodate oxidation and degradation of Smith showed the backbones of sugar residues chain in LBP were mainly connected by 1-3 and 1-4. UV spectroscopy results showed that LBP did not contain nucleic acid, contain little protein. Infrared spectroscopy results showed LBP contained -OH,-NH2,-NH-,-CH2, C=O,-CO,-C-O,-COOH. SEM results showed the form of LBP was sheet or bunchy. AFM results showed LBP gathering together formed random balls and islands large or small.LBP could inhibit growth of the human hepatocarcinoma cells SMMC-7721, and bioactivities of LBP-5 was more active than LBP-4.The morphological observation by inverted microscope and laser scanning confocal mircroscope showed that human hepatocarcinoma cells SMMC-7721 treated by LBP underwent apoptosis. The cells treated by LBP-4 were blocked in G0/G1-phase and other cells treated by LBP-5 were blocked in S-phase.