丙醇-硫酸铵双水相体系集成提取桑叶中植物多酚的研究

目的]为双水相技术的应用和桑叶开发提供依据。方法]将桑叶粉碎,用石油醚超声波提取30 min过滤,滤渣中加入丙醇与水混合溶液60 ml和13.2 g的硫酸铵形成双水相体系,以超声提取植物多酚,测定其中植物多酚含量,计算植物多酚得率。结果]在丙醇-水双水相体系中,当(NH4)2SO4用量为0.30 g/ml,醇-水比为0.6时,可获得稳定的双水相和较高植物多酚得率。超声时间达20 min时,桑叶植物多酚得率达到最大。该法对桑叶中植物多酚的提取率为1.83%,提取物植物多酚含量为24.1%,明显高于回流提取法。结论]超声波与丙醇-硫酸铵双水相体系耦合提取桑叶中的植物多酚,可缩短提取时间、提高得率,降低提取温度,有利于热敏成分的分离,获得高纯度高活性的生物活性物质。

Study on Plant Polyphenol Extraction from Mulberry Leaves by Propyl Alcohol-Ammonium Sulfate Aqueous Two-phase System Coupling with Ultrasonic

Objective] The study was to provide the theoretical basis for the application of aqueous two-phase technique and the development of mulberry leaves. Method] The mulberry leaves were extracted and filtered with petroleum ether ultrasonic for 30 min after comminution,and 60 ml mixed solution of water and propyl and 13.2 g alcohol-ammonium sulfate were added into filter residue to form the aqueous two-phase system.The plant polyphenol was extracted with ultrasonic and the polyphenol content was detected and its extraction rate was calculated.Result] In propyl alcohol-ammonium sulfate aqueous two-phase system,the stable aqueous two-phase system and higher extraction rate of plant polyphenol were obtained when the dosage of(NH4)2SO4 was 0.30 g/ml and the ratio of alcohol and water was 0.6.The extraction rate of plant polyphenol from mulberry leaves was highest when the ultrasonic time was 20 min.By using this extraction method the extraction rate of plant polyphenol from mulberry leaves was 1.83%,and the polyphenol content in plant extraction was 24.1%,which were obviously higher than that by reflux extraction.Conclusion] With the method of ultrasonic coupling with Propyl-alcohol ammonium sulfate aqueous two-phase system to extract plant polyphenol from mulberry leaves,the extraction time could be shorten and the extraction rate was increased.Decreasing the extraction temperature was beneficial to separate the heat-sensitive ingredients,and got bioactive substances with high purity and high activity.