桑类药材多羟基生物碱分离的研究进展

桑科植物Morus alba的药材,包括桑叶、桑枝、桑白皮(根皮)均含有多种多羟基生物碱,多羟基生物碱具有良好的降血糖、降血脂、抗病毒、提高免疫力、抗衰老等药理作用,但多羟基生物碱与在大多数植物中常见的糖类物质结构也相似,且具有强极性及碱性,所以其分离纯化将是复杂艰难的工作,分离步骤繁琐,通常需要多次柱色谱。查阅文献后,还未见到有关分离多羟基生物碱固定相材料方面的综述。因此,作者就桑类多羟基生物碱的分离,包括:反相、正相、离子交换、亲水色谱方面进行了综述,且针对每种分离方法都分析了其优点与不足,并提出以硅胶键合离子液体为新型吸附材料的柱色谱的方法,这种新型材料具有与亲水色谱中两性离子固定相类似的结构特点,不同点是该固定相中阴阳离子之间是离子键连接,同时其显示出特殊的分离特性-“两性”的特点,以期为桑类药材中多羟基生物碱的分离提供帮助以及为新型桑类药物的开发提供有价值的参考,成功分离多羟基生物碱也将为不同类型糖尿病的病人更针对性地用药提供条件。最后对新型硅胶键合离子液体固定相用于分离多羟基生物碱的发展和应用前景进行展望,其突出的优势为在色谱分析中,可根据离子液体的可调控性,来设计性的修饰固定相。

Advance in Studies on Polyhydroxylated Alkaloids Isolated from Mulberries

Mulberry Morus alba includes multiple polyhydroxylated alkaloidsi in leaves, branches root barks, which have many pharmacologic effects in reducing blood sugar and blood lipid, resisting virus, enhancing immunity and anti-aging. However, because spolyhydroxylated alkaloids share a similar structure with common carbohydrates in plants, with a strong polarity and alkalinity, they are hard to be separated and purified, which needs complicated separation procedures and multiple column chromatography. Furthermore, there is no literature about stationary phase materials for separating polyhydroxylated alkaloids. Therefore, the authors summarized the separation procedures for mulberry polyhydroxylated alkaloids, including reversed-phase liquid chromatography (RPLC), normal phase liquid chromatography(NPLC), ion exchange chromatography (IEC) and hydrophilic interaction chromatography (HILIC), analyzed their advantages and disadvantages, and proposed the column chromatography method with carbosilane ionic liquid with a new-type adsorbing material. This new-type material is similar with zwitter-ion stationary phase in hydrophilic interaction chromatography but different in the ionic bond connecting zwitterions in the stationary phase, while showing the characteristic zwitter-ion separation, in order to provide reference for separating polyhydroxylated alkaloids from mulberry herbs and developing new-type mulberry drugs, successfully separate polyhydroxylated alkaloid and develop targeted drugs for patients with different types of diabetes. Finally, the authors defined the development and application prospect of polyhydroxylated alkaloids, which can modify the stationary phase in the chromatographic analysis by regulating the ionic liquid.