人参皂苷水相助溶方法的研究

Solubilization of Ginsenosides in Aqueous Solution

目的:寻找增加人参皂苷水相溶解度的方法。方法:在不同pH、温度、搅拌时间和使用潜溶剂的条件下,分别于水溶液中溶解人参茎叶皂苷和单体皂苷Rb1、Rg1、Re,分光光度法测定所试人参皂苷的溶解量。结果:在pH6.0～8.0范围内,人参茎叶总皂苷、Rb1、Rg1的溶解量随着pH的降低而增大;Re溶解量则在pH为7.0时最大。在5～35℃的范围内,人参皂苷溶解量均随着温度的增高而增加。搅拌时间在一定范围内延长,可通过加速助溶作用而提高人参皂苷的溶解量。乙醇或丙二醇对人参皂苷均有助溶作用,乙醇+丙二醇的助溶效果更好。二甲基亚砜除了能使单体皂苷Re的溶解量稍有增高外,反而使人参茎叶皂苷、Rb1、Rg1的溶解量降低。结论:在适当pH值、温度和搅拌条件下,使用乙醇和丙二醇是人参皂苷水相溶解的有效助溶方法。

Objective： This study was conducted to seek the approaches to the water - phase solubility enhancement of ginsenosides （GSs）. Methods ： Under the conditions of control of pH, temperature and stirring, and use of cosolvents, individual ginsenosides - Rb1, - Rg1 and - Re （ G-Rb1, G-Rg1 and G-Re）, and ginsenoside of stem and leaf （GSL） were dissolved in aqueous solutions respectively. The amounts of dissolved GSs were determined by absorption spectrometry. Results ： In the pH range 6.0 - 8.0, the amounts of dissolved G-Rb1, G-Rg1 and GSL were increased with the decrease in pH of solutions. However, the maximum of dissolved G-Re was observed at pH 7.0. The solubility of the GSs increases when the temperature of solutions rises over a range of 5 - 35℃. Prolonging stirring, dissolved GSs were increased owing to the speeding-up in dissolution. Either ethanol or propylene glycol can increase the amounts of dissolved GSs in aqueous solutions. And mixture of these two cosolvents had a greater effect of solubilization on GSs. Under the use of dimethyl sulfoxide, dissolved G-Re was increased to some extent, whereas G-Rb1, G-Rg1 and GSL were dissolved at lower levels in the water phase. Conclusion. Tire ginsenosides can be solubilized effectively by ethanol or propylene glycol in aqueous solutions under the suitable conditions of pH, temperature and stirring.