Study On Extraction, Isolation, Purification And Antioxidant Activity Of Polysaccharide From Camellia Oleifera

Camellia oleifera Abel (from Theaceae family), is special oil plants in our China. According to the analysis data, the content of carbohydrates in oil-tea-cakes, which is residue after processing tea oil oil-tea seed, is30%～60%. Polysaccharide has various biological activities, such as lowering blood-glucose, lowering blood fat, anti-tumor, anti-infection and treatment of AIDS. So it will be very meaningful to study on extraction, isolation and purification, antioxidative activities of active polysaccharide from oil-tea-cakes.In this paper, with oil-tea-cakes(bought from Liuyang) as raw materials, the extraction process of the tea saponin and polysaccharide was researched; COP was treated with activated carbons to decolorize; after preliminary purification of Camellia Oleifera Polysaccharide with SephadexG-100column chromatography, the purity of polysaccharides were identified by liquid chromatography (HPLC) analysis; we made use of UV scanning analysis, infrared spectroscopy analysis of polysaccharide structure of the preliminary study; antioxidant activity of Camellia Oleifera Polysaccharide in vitro was studied. In this paper, the results of the study are as follows:1. Using the ethanol as the extracting agent, the tea saponin in oil-tea-cakes were extracted. The optimal conditions were obtained through experiments:the concentration of ethanol is80%, the solid-to-liquid ratio is1:9(g/mL), time at4h, the temperature of extracting is90℃. Under these conditions, the yield of tea saponin is8.98%.2. Camellia Oleifera Polysaccharide studied process of water to explore the extraction temperature, extraction time, ratio of material to liquid ratio of polysaccharide to the effects achieved. On the base of single-factor test, the orthogonal experiment was used to determine the optimum extraction conditions. The results showed that the optimal extraction conditions of polysaccharide were determined as below:extraction temperature70℃, ratio of material to liquid1:30(g/mL), and extraction time4h. Under these conditions, the yield of polysaccharide was5.88%.3. Camellia Oleifera Polysaccharide was treated with activated carbons to decolorize. By the means of single factor and orthogonal test, we can get the best parameters as follows: the dosage of activated carbon was0.2g/100mL, decolorization temperature was60℃and decolorization time was1.5h. Under the optimal parameters, the decolorization rate was81.66%, and the remaining ratio of polysaccharide was82.11%. Camellia Oleifera Polysaccharide was preliminary separated and purified by SephadexG-100column chromatography, it was obtained two components COP1and COP2by the distilled water eluting. COP1and COP2was (?)ll a homogeneous polysaccharide identified by liquid chromatography (HPLC) analysis. There were no proteins or nucleic acids in polysaccharides through UV spectra analysis. Three kinds of polysaccharides all had typical characteristic absorption peaks of polysaccharides by use of IR spectra.4. By establishing the reaction system of DPPH free radical, superoxide anion radical, hydroxyl radical and reducing power, antioxidant activity of Camellia Oleifera Polysaccharide with different doses in vitro was studied and compared with antioxidant activity of VC. The results showed that COP has a certain antioxidant activity in vitro and the antioxidant activity increased with increasing concentration. The IC50of COP were9.729mg/mL、0.987mg/mL、3.537mg/mL on DPPH free radical, superoxide anion radical, hydroxyl radical. The antioxidant activity of COP exist difference with VC comparing.