二苯乙烯苷及其β-环糊精包合物的稳定性研究

The stability study of stilbene glucoside and its β-cyclodextrin inclusion complex

目的明确影响二苯乙烯苷及其β-环糊精包合物稳定性的因素。方法以β-环糊精与二苯乙烯苷用量比、包合时间、包合温度为影响因素,按L9(34)正交实验筛选包合条件;利用高效液相色谱法,以二苯乙烯苷含量为指标,分别考察了人工胃液、人工肠液及醋酸-醋酸钠缓冲液、氨-氯化铵缓冲液、光照对二苯乙烯苷及其β-环糊精包合物稳定性的影响。结果 (1)根据正交实验结果,确定最佳包合条件为:8倍量的β-环糊精,包合时间为2小时,包合温度为35℃;(2)12小时内,二苯乙烯苷未包合物的含量在人工胃液中由100%下降至79.7%,在醋酸-醋酸钠缓冲液中由100%下降至15.9%;β-环糊精包合物中二苯乙烯苷含量在人工胃液中1小时达到100%,在醋酸-醋酸钠缓冲液中2小时达到100%,随后受酸度影响逐渐下降。二苯乙烯苷未包合物在人工肠液及氨-氯化铵缓冲液中的稳定性差,几乎无法存在;其β-环糊精包合物的稳定性有所改善,在肠液中0.5小时含量达95.8%,之后未检出;在碱性缓冲液中4小时达到峰值,6小时后未检出。光照条件下,48小时后二苯乙烯苷的含量由100%下降至50.2%;β-环糊精包合物的含量在实验条件下明显得到改善,48小时后含量仍可达90.5%。结论二苯乙烯苷及其β-环糊精包合物在酸性环境下较碱性条件下稳定;在酸性溶液中,随着溶液酸性增强,其稳定性变差;β-环糊精包合物的稳定性明显强于未包合物,说明利用β-环糊精对二苯乙烯苷进行包合可以在一定程度上使其稳定。

Objective To make certain the influence factors of affecting the stability of stilbene glucoside and its β-cyclodextrin inclusion complex. Methods The β-cyclodextrin inclusion of stilbene glucoside was conducted according to an L9（ 34） orthogonal experiment design with three factors,namely the ratio of β-cyclodextrin amount to stilbene glucoside,the time and temperature of inclusion. The contents of stilbene glucoside were detected by HPLC in a simulated gastric fluid,a simulated intestinal fluid,an acetic acid-sodium acetate buffer solution,an ammonia-ammonium chloride buffer solution,and under illumination,respectively. Results 1. Optimal inclusion conditions from orthogonal experiments were an amount of β-cyclodextrin 8 times as much as that of stilbene glucoside,an inclusion time was 2. 0 h and inclusion temperature was 35℃. 2. The content of stilbene glucoside without β-cyclodextrin inclusion in the simulated gastric fluid went down from 100% to 79. 7% in 12. 0h,and in the acetic acid-sodium acetatebuffer solution declined from 100% to 15. 9%. The content of the β-cyclodextrin inclusion complex of stilbene glucoside in the simulated gastric fluid went up to 100% in 1. 0 h and 2. 0h in the acetic acid-sodium acetate buffer solution,and afterwards went down gradually influenced by the acidity of the fluid. Stilbene glucoside without β-cyclodextrin inclusion was very unstable in the simulated intestinal fluid and the ammonia-ammonium chloride buffer solution. The β-cyclodextrin inclusion complex of stilbene glucoside was more stable,and the content was reached 95. 8% in the simulated intestinal fluid in 0. 5h,and became undetectable afterwards,and it was reached peaked in 4. 0 h and became undetectable in 6. 0 h in the alkaline solution. Under illumination,the content of stilbene glucoside without β-cyclodextrin inclusion went down from 100% to 50. 2% in 48. 0h,and its β-cyclodextrin inclusion complex was more stable with the content of 90. 5% in 48. 0h. Conclusion Stilbene glucoside and its β-cyclodextrin inclusion complex are more stable in an acid solution than in an alkaline solution. In acid solution,the stability becomes weaker with the increment of the acidity. The stability of the β-cyclodextrin inclusion complex of stilbene glucoside is stronger than without β-cyclodextrin conclusion. β-cyclodextrin can be used to make stilbene glucoside more stable as an inclusion complex.