野菊花总黄酮的提取及萃取精制研究

摘要

In this study, ethanol-water solution was used to leach flavonoids from the flower buds of Chrysanthemum indicum L, and the crude leaching-out products were purified by liquid-liquid extraction. In the leaching process, the influences of ethanol concentration, ratio of solid to liquid, temperature, leaching time and leaching times on yield of the total flavonoids were investigated; while in the liquid-liquid extraction process, a suitable extractant was chosen and the influences of feed concentration, phase ratio and extraction times on the yield of the total flavonoids and purity were studied. It turns out that the suitable conditions are as follows: 1) leaching process:ethanol-water (7:3, v/v) as leaching solution, temperature of 60℃, ratio of solid to liquid of 20:1 mL⋅g−1, leaching time of 1 hour, leaching times of one;2) extraction process:temperature of 25℃, extractant of water-saturated n-butanol, feed concentration of 15 g⋅L−1, phase ratio of 1 and extraction times of three. Under the above conditions, the purity of total flavonoids in the extract after liquid-liquid extraction is 32.4%. Furthermore, it was found that the purities of extracts obtained at the second and third times of extraction are higher than 60%, thus these extracts can be used as raw material for the further separation and purification of flavonoid monomer.%　　用乙醇水溶液从野菊花中提取总黄酮，再用液-液萃取法进行萃取精制。提取阶段考察了乙醇浓度、液固比、温度、提取时间和提取次数对提取得率的影响，萃取阶段则考察了萃取剂种类、原料液浓度、相比和萃取次数对萃取率和萃取物纯度的影响。通过工艺优化，建立了一条从野菊花中提取总黄酮的工艺路线，即取40~50目的野菊花粉，加入70％的乙醇水溶液，液固比为20：1 mL⋅g−1，在60℃下搅拌回流提取1 h，将提取液蒸干得野菊花浸膏；将野菊花浸膏重新溶解制成15 g⋅L−1的水溶液作为原料液，加入水饱和的正丁醇作为萃取剂，相比为1，在25℃下振荡萃取1 h，萃取3次，所得萃取物的总黄酮纯度为32.4%。在多次萃取时还发现，第2、3次萃取物的总黄酮纯度较高(大于60%)，可作为进一步分离提纯黄酮单体的原料。