【作者】 冯涛；

【导师】 吕晓玲；

【作者基本信息】 天津科技大学 ， 食品科学， 2003， 硕士

【摘要】 本文首先对竹叶中总黄酮的含量进行了测定，得每克干竹叶中总黄酮含量为13.65mg，与文献报导的用甲醇浸提，用WYGC18色谱柱，以甲醇:水:磷酸(60:40:0.5)(v:v:v)为流动相，以254nm为检测波长，测定的竹叶中黄酮总量在5.9～13.1mg/g的范围基本相符。 其次对竹叶中黄酮的最佳提取条件进行了研究，确定了乙醇浸提是最佳的提取方法，确定了64％(v/v)乙醇，料液比1:30(w/v)，浸提时间6小时，温度80℃，浸提2次，pH值10.5为竹叶中黄酮的最佳浸提条件。在此条件下所得浸提液的吸光值可达0.286，即每克干竹叶的浸提液中含有黄酮12.41mg，则可得浸提率为90.59％。 然后对竹叶提取液中黄酮的纯化进行了研究，得出竹叶黄酮的最佳精制条件为：以大孔吸附树脂ADS-17为竹叶黄酮的专用分离树脂，采用吸附流速为3mL/min，洗脱流速为1.5mL/min，径高比为1:7.5，吸附原液pH值为9，洗脱剂选择40％乙醇溶液，洗脱剂用量为3BV(树脂床体积)。在此条件下得到的洗脱液再采用真空冷冻干燥的方法，得到竹叶黄酮的黄褐色粉末。 最后对竹叶黄酮的黄褐色粉末进行了鉴定，得：产品中黄酮纯度为28.04％，经ADS-17树脂依次吸附、洗脱后，产品中黄酮纯度变为原来上柱前样液的3.274倍，提高约2倍多，产品黄酮得率为3.744％。产品中总糖含量的测定结果为38.65％，含氮化合物含量(以蛋白质量计)仅为1.58％；利用颜色反应检验产品中黄酮类化合物可能属于黄酮醇类或黄酮类，利用薄层层析定性产品中黄酮类化合物可能属黄酮类，利用紫外光谱定性产品中黄酮类化合物具有黄酮的吸收光谱特征，综上所述，可以确定产品中黄酮类化合物可能属黄酮类。更多还原

【Abstract】 Firstly, the total flavonoids content of the bamboo leaf was determined in this paper. It was concluded that the total flavonoids content of per gram dry bamboo leaf was 13.65 milligram, the result was basically consilient with the result which was reported by reference literature. In this literature, the range of 5.9-13.1 mg/g of the total flavonoids content of bamboo leaf was determined by methanol extraction , taking WYGC18 as chromatogram column, taking methanol: water: phosphoric acid(60:40:0.5)(v:v:v) as mobile phage, and taking 254nm as determining wavelength.Secondly, the optimal extracting conditions of bamboo leaf flavone(the abbreviation is BLF) were studied, and it could be determined that alcohol soaking was the best extraction method and 64% alcohol(v/v), the 1:30(w/v) of material and alcohol ratio, 6 hours of extracting time, 80 癈 of temperature, 2 times of extraction ,10.5 of pH value were the best extraction conditions of the BLF. At these conditions, the absorbency of extracting solution could reach 0.286 , the extracting rate was 90.59%.Then the purification of BLF was studied, and the optimal purification conditions were concluded that the macroporous adsorption resin ADS-17 was selected as exclusive separation resin of BLF, the adsorption velocity was 3mL/min, elution velocity was 1.5mL/min, diameter and height rate was 1:7.5, the pH value of under-adsorpted solution was 9, the elution solvent was 40% alcohol, and the quantity of elution solvent was 3BV( resin bed volume, its abbreviation is BV). Then the eluent which got from above conditions was dehydrogenized by vacuum freezing drying method, the tan powder of BLF was collected.Finally, the tan powder of BLF was evaluated. And so the conclusion were : the purity percentage of BLF was 28.04% , after adsorpted by ADS-17 resin and eluted by 40% alcohol, the purity percentage of BLF became 3.274 times of the pre-adsorpted solution, increased 2 times or more, the yield rate of BLF in product was 3.744%; The total saccharide content of product was 38.65%, and the content of the compound containing nitrogen of product(calculated as protein) was only 1.58%; the flavonoids of product detected by color reaction could belong to flavonol or flavone, the flavonoids in product detected by TLC could belong to flavone , the absorption spectrum of flavonoids in product detected by ultraviolet spectrometer had the characteristics of the absorption spectrum of flavone . So from above , it can bedetermined that the flavonoids in product probably was or were a kind or kinds of flavone.更多还原