【作者】 王丽；

【导师】 王振宇；

【作者基本信息】 哈尔滨工业大学 ， 生物化工， 2012， 硕士

【摘要】 花粉是植物的全营养库，富含多种活性物质，具有抗肿瘤、抗辐射、促进淋巴细胞增殖等作用。本文选取花粉作为研究对象，系统的研究了不同花粉体外抗氧化活性、促骨髓干细胞增殖活性，以及荞麦花粉水提物对小鼠和干细胞辐射诱导氧化伤害的防护作用，对研发低毒、有效的辐射防护剂有重要的意义。本研究主要内容如下：选取绿茶花粉、荞麦花粉等12种花粉为原料，经蒸馏水、70%乙醇超声提取，以ABTS及羟基自由基清除率为指标，测定其体外抗氧化能力，筛选出抗氧化能力相对较强的花粉：银杏花粉、荞麦花粉、五味子花粉和荷花花粉。采用MTT法测定12种花粉水提物及70%醇提物对大鼠股骨骨髓干细胞的增殖活性，结果显示，花粉水提取物对干细胞的促进作用高于醇提取物，且荞麦花粉水提物在较高浓度时（1mg/mL）促骨髓干细胞增殖活性最高，可达到74%。本课题采用60Coγ-射线构建辐射模型，对小鼠连续灌胃荞麦花粉水提物（WEPB）21天后发现，荞麦花粉水提物对小鼠白细胞、脾脏和肝脏等免疫器官均具有保护作用，且能显著提高单核-巨噬细胞的吞噬能力、脾淋巴细胞的转化增殖能力、小鼠组织SOD活性、小鼠骨髓DNA含量及骨髓干细胞存活率，降低脂质过氧化的产物MDA含量及小鼠骨髓微核率，说明荞麦花粉水提物主要是通过提高内源性抗氧化物酶活性而增强抗氧化能力、免疫能力以及促进干细胞增殖而降低DNA损伤达到保护小鼠免受辐射损伤的作用。荞麦花粉水提物主要组成成分为糖（75%）及蛋白质（6%）。氨基酸分析发现，荞麦花粉水提物富含多种氨基酸，其中谷氨酸含量最高，其次为天冬氨酸，赖氨酸、苏氨酸、丝氨酸。GS-MS分析，证实荞麦花粉水提物单糖组分主要由核糖、鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖及半乳糖组成，其摩尔比是0.35：0.95：27.78：0.93：1.70：13.19：16.16。更多还原

【Abstract】 Pollen contains all nutrients which are necessary for plant growth anddevelopment and possess the pharmacological action of anti-tumor, anti-radiation andproliferation of lymphocyte. The current study was aimed to elucidate the antioxidantand proliferation of bone marrow stem cells properties of the extracts of pollen, andradioprotective properties of the water extract of buckwheat pollen. It is very essentialin the development of radioprotective agents with lower toxicity and higher efficacyin biology and medicine. The main contents of this study were stated as the following:In the present investigation, the water and70%ethanol extracts12kinds of thepollen, included green tea and buckwheat, were extracted by ultrasound and furtherevaluated for their antioxidant activities (ABTS and hydroxyl radicals scavengingpotential activities). The extracts of pollen of ginkgo, buckwheat, schisandra and lotusshowed very strong radical-scavenging activity in both the assays.Water and70%ethanol extracts of12pollen promoted proliferation of murinebone marrow stem cells was assessed using MTT assay.Proliferation-promotingactivity of water extracts of pollen was higher than70%ethanol extracts. And thewater extract of the pollen of buckwheat showed strong activity, peaking at1mg/mLto75%.The water extract of the pollen of buckwheat (WEPB) was evaluated for in vivoradioprotective activity against whole body60Co γ-ray irradiation in mice. Pretreatedwith WEPB by intragastric for21days was found to be effective in preventingradiation injure. Further, administered WEPB could effectively increased white bloodcells (WBC) in peripheral blood, and prevent spleen and liver damage in irradiatedmice, and promote the phagocytic capacity of monocytes–macrophages, splenocyteproliferation index, the activities of endogenous antioxidant enzymes(SOD), quantityof marrow DNA and survial of bone marrow stem cells and reduced the radiationinduced micronuclei, the content of MDA. Thus WEPB possess a strong whole bodyradioprotective activity, and these observations suggest that WEPB could bedeveloped as a poteinal preventive drug for ionizing irradiation induced injury viaenhancing the antioxidant activity and induction of DNA damage.The main constituent of WEPB consisted75%polysaccharides, and6%protein.The amino acid analysis showed that WEPB was rich in a variety of amino acids,glutamate was highest, followed by aspartic acid, lysine, threonine, serine.Monosaccharide composition showed that WEPB consist of ribose, rhamnose,arabinose, xylose, mannose, glucose and galactose, the molar ratio between monosaccharide is0.35:0.95:27.78:0.93:1.70:13.19:16.16.更多还原