Study On The Extraction, Immune Enhancement And Hyperlipemia Prevention Function Of Onion (Allium Cepa L.) Polysaccharide

Onion (Allium cepa L.) is a traditional drug-food herb in Asia, it has a special effect on the prevention and curing of many diseases. The polysaccharide in the waste produced after manufacturing of onion is one of the biologically active contents, to extract polysaccharide from the waste can enhance the appendix value and made thorough use of the material.In this dissertation the detection method, the water extraction method, the protein removal method and the immune function were studied. The results were summarized as follows: (l)The optimal condition for the extraction of onion polysaccharide by hot water was established. The effects of extraction time, extraction temperature and material to water ratio on the yield of onion polysaccharide were investigated. The optimal parameters were: extraction time 4h, extraction temperature 70℃ and material to water ratio 1:25, the yield of onion polysaccharide reached 4.236% under the condition established.(2)The optimal condition of the removal of protein in the onion polysaccharide was established. The effects of the quantity of sevag reagent, the chloroform to n— butyl ethanol ratio and time of removal were investigated. The optimal parameters of the removal of protein in the onion polysaccharide were: the quantity of sevag reagent 1/2, the chloroform to n—butyl ethanol ratio 4:1 and the removal time 3.(3)The immune function of onion polysaccharide was approved. The result showed that the DTH value increased by 48.57% (p <0.05) and the HC₅₀ value increased by 23.08% (p <0.05) in the mice fed in low dosage team; the DTH value increased by 50%( p <0.05), the PFC amount inceased by 39.62%( p <0.05) and the HC₅₀ value increased by 26.5%( p <0.05) in the mice fed in medium dosage team; the DTH value increased by 55.71%( p <0.05), the annex rate of macrophages increased by 81.25%( p <0.01) and the annex index of macrophages increased by 84.09%( p <0.05) in the mice fed in high dosage team.(4)By the method of hyperlipemia prevention, low, medium and high-dosage of onion polysaccharide could prevent the increase of TG concentration in SD mice serum (P<0.05); low-dosage onion polysaccharide could prevent the increase of TC concentration in SD mice serum(P< 0.05); low, medium-dosage onion polysaccharide could increase HDL-C concentration in mice serum(P< 0.05). Low-dosage of onion polysaccharide could prevent the increase of blood lipid concentration and had the function of hyperlipemia prevention.