Study On Extraction,Isolation And Antioxidant Of Pollen Polysaccharide From Ginkgo Biloba

In this paper, the wall-breaking methods of pollen from Ginkgo biloba, Ginkgo pollen polysaccharide extraction, separation and purification, and the antioxidant characteristics of Ginkgo pollen polysaccharide were studied. The results were as follows:1. The optimum craft parameters of wall-breaking by homogenate machine were: the speed 15000r/min, the ratio of gardenia to liquid 1:50,operation time 10min, and the breaking rate was 99.6%.2. The optimum conditions for ultrasonic assistant extraction of Ginkgo biloba pollen polysaccharide were as follows:the ratio of solid to liquid 1:50, ultrasonic power 700W, and ultrasonic time of 50min, and the pollen polysaccharide extraction rate was up to 6.05%.3. Protein was removed from polysaccharide through three kinds of methods. It was found that by Sevag method of removing protein, the protein removal rate was 82.3%, and polysaccharide retention rate was 10.9%. The optimized conditions were showed, when time of decolorization was 4h, decolorization temperature was 50℃, the dosage of granular activated carbon 0.15g/ml, the decoloration rate of polysaccharide was 72.84%, and the retention rate of polysaccharide was 88.19%.4. Ginkgo pollen polysaccharides were separated by DEAE-cellulose. Three main sub-class compositions were abtained as PGBPⅠ, PGBPⅡand PGBPⅢ. In order to get a single homogeneous polysaccharide component, Sephadex G-200 column chromatography was used to those substances which were separated by DEAE-cellulose column chromatography, and the three main kinds of polysaccharide, named PGBPⅠa,PGBPⅡa and PGBPⅢb, were gained with the recovery were 71.11%, 81.2% and 73.02%, respectively.5. In the four kinds of free radical scavenging effect, PGBPⅠa was effective to the hydroxyl radical, sodium nitrite and DPPH? radical scavenging, PGBPⅡa, to hydroxyl radical and superoxide anion radical scavenging, and PGBPⅢb, to superoxide anion, sodium nitrite, especially more effective to DPPH? scavenging.To PGBPⅢb, scavenging effect to superoxide anion radical was stronger than the same concentration of Vc in solution. In all, PGBPⅢb was a better antioxidant.