构树叶中黄酮提取分离工艺的优化

Process Optimization of Extracting and Separating Flavonoids from Broussonetia papyrifera Leaves

[目的]研究干构树叶中黄酮的提取和分离工艺。[方法]采用超声波辅助乙醇提取构树叶中黄酮,在单因素试验基础上进行了正交试验,并对黄酮提取物进行了分离纯化。[结果]各因素对黄酮提取率的影响从大到小次序为料液比、超声时间、乙醇浓度、超声温度。在超声频率40 k Hz下,最佳提取工艺条件为料液比1∶30(g∶ml)、超声时间40 min、乙醇浓度50%、超声温度50℃,黄酮提取得率可达4.01%。在最佳条件下提取构树叶,减压浓缩提取液后加入石油醚萃取,水相用盐酸酸化至p H=2,再加入乙酸乙酯萃取,酯相减压回收溶剂得到提取产物,产物得率为5.94%,其中黄酮质量含量为35.36%。[结论]该工艺简单易行、稳定性好,提取物中黄酮含量较高。

Abstract [ Objective ] The research aimed to study the process of extracting and separating flavonoids from dry Broussonetia papyrifera leav- es. [ Method ] Ultrasonic assisted ethanol extraction was used to extract flavonoids from dry Broussonetia papyrifera leaves. An orthogonal test was done in addition to single-factor test, and flavonoid extracts were separated and purified. [ Result ] The factors affecting flavonoid extraction, in descending order, were material liquid ratio, ultrasonic extraction time, ethanol concentration, and ultrasonic extraction temperature. Using 40 kHz ultrasonic, the optimal process of extracting from dry Broussortetia papyrifera leaves was using 1 ： 30（ g： ml） material liquid ratio and 40 minutes long ultrasonic extraction, with 50% ethanol and 50 ℃ ultrasonic extraction temperature, and flavonoid extraction yield could reach 4.01%. The optimal extraction process was applied to dry Broussonetia papyrifera leaves to obtain extract liquid first, and then petroleum ether was used to extract the vacuum concentrated extract liquid. After adjusting extract liquid＇ s aqueous phase to pH = 2 by hydrochloric acid, ethyl acetate was used to extract again, and then product was obtained by ester phase vacuuming recovery solvent. Product yield was 5.94% and its flavonoid content was 35.36%. [ Conclusion]This process was easy, stable, and brought relatively high flavonoid contents in product.