六种大豆异黄酮溶液的稳定性

用制备液相色谱仪(Shimadzu LC-20AP)制备了大豆苷、黄豆黄苷、染料木苷、大豆素、黄豆黄素、染料木素6种大豆异黄酮单体溶液,对其进行了1个月的短期稳定性和6个月的长期稳定性研究,特性量值为溶液的浓度值和纯度值。对在4个不同温度(–20℃、4℃、25℃、60℃)下保存一个月后的测定值与初始值进行了方差分析,短期稳定性试验结果表明,除染料木苷外,其余5种色谱纯大豆异黄酮溶液的浓度在4℃、25℃条件下保存无显著变化,6种大豆异黄酮溶液的纯度在–20℃、4℃、25℃条件下保存无显著变化,因此认为4℃、25℃是大豆异黄酮溶液短期储存的最适温度。在4℃条件下,对经过0、1、2、3、4、6、8、12、16和24周的大豆异黄酮测定值与初始值进行t检验,长期稳定性结果表明,6个月的保存期内6种色谱纯大豆异黄酮溶液的纯度无显著性变化,但浓度均显著增加,分析认为分装容器的密封性是导致浓度增加的原因。本研究结果为大豆异黄酮单体溶液标准溶液产业化提供了技术支撑。

Stability of Six Soybean Isoflavones Solution

Six chromatographic grade soybean isoflavones solutions daidzin, glycitin, genistin, daidzein, glycitein, and genistein were prepared with a preparative high performance liquid chromatography (Shimadzu LC-20AP). The solution stabilities were monitored in changes of concentrations and purities during a one-month period under temperatures of –20°C, 4°C, 25°C, and 60°C, respectively, and during a six-month period under a temperature of 4°C. Variance analysis of the one-month period experimental results indicated that the concentrations of five soybean isoflavones solutions showed no obvious change under 4°C and 25°C except for genistin solution. No obvious changes in purities for all soybean isoflavones solutions under –20°C, 4°C, and 25°C were observed. Temperatures of 4°C and 25°C were suggested for short-term storage of soybean isoflavones solutions. The t-test of the six-month period experimental results indicated that the concentrations of six chromatographic grade soybean isoflavones solutions increased significantly, but the purities of those did not change after 0, 1, 2, 3, 4, 6, 8, 12, 16, and 24 weeks preservation at 4°C. Leakage of methanol from containers of isoflavones solutions was considered to be the course of concentration increment. This research provided technical helps for the production of the soybean isoflavones standard solutions.