超声波辅助乙醇提取桑叶多酚的工艺条件优化

Process Optimization for Ultrasound-assisted Ethanol Extraction of Polyphenols from Mulberry Leaf

多酚是桑叶中的重要药用活性成分。以桑叶粉为原料,采用超声波辅助乙醇提取方法提取桑叶多酚。在超声波功率为160 W的条件下进行单因素试验的结果表明,提取工艺中的乙醇体积分数、料液质量浓度、提取温度和提取时间对桑叶多酚提取得率均有影响。正交试验显示这4种因素对桑叶多酚提取得率的影响作用大小依次为料液质量浓度、提取温度、提取时间和乙醇体积分数。优化的提取工艺条件为:桑叶粉质量浓度33.3 g/L,乙醇体积分数60%,超声波功率160 W,提取温度50℃,提取时间20 min。在此优化工艺条件下,桑叶多酚的得率达到3.51%。与仅用乙醇浸提桑叶多酚的方法相比,超声波辅助提取可明显缩短提取时间,提高提取效率。

Polyphenols are important medicinal active ingredients in mulberry leaves. Mulberry leaf powder was used as material for extraction of polyphenols with ultrasound-assisted ethanol extraction method. The results from single factor experiment under 160 W ultrasound power showed that ethanol concentration, material mass concentration, extraction temperature and extraction time could affect the yield of polyphenols from mulberry leaf. Orthogonal experiment demonstrated that the four factors affected the extraction were in the order of material mass concentration, extraction temperature, extraction time and ethanol concentration. The optimum extraction condition for mulberry leaf polyphenols was as follows; material mass concentration 33.3 g/L, volume fraction of ethanol solution 60%, ultrasound power 160 W, extraction temperature 50 ℃, and extraction time 20 min. Under this optimized condition, the yield of polyphenols from mulberry leaf was 3.51%. Compared with conventional ethanol extraction, ultrasound-assisted extraction can obviously shorten the extraction time and improve extraction efficiency.