知母皂苷BⅡ在模拟人体胃肠道环境及生物样品中的稳定性研究

Stability of Timosaponin BⅡ in Simulated Conditions of Human Stomach, Intestines and in Biological Fluids in Vitro

关键词:  知母皂苷BⅡ  人工胃肠液  生物样品  pH液

Key words:  timosaponin BⅡ  artificialgastrointestinal fluid  biological sample  pH fluids

摘要:

目的 考察知母皂苷BⅡ在不同生理pH介质和生物样品中的体外稳定性。方法 取知母皂苷BⅡ分别在不同生理pH介质（pH 1.2，6.8，7.4，8.0）的缓冲液、人工胃液、无蛋白酶人工胃液、人工肠液、无蛋白酶人工肠液介质和离体生物介质中进行孵育，利用HPLC测定不同介质中知母皂苷BⅡ的含量变化，考察知母皂苷BⅡ的降解情况及酶稳定性。结果 知母皂苷BⅡ在不同生理pH介质溶液中9 h内未发生明显降解，在离体大鼠大肠和小肠及其内容物中发生明显降解。结论 知母皂苷BⅡ在模拟人体胃肠道环境的溶液中很稳定，不会发生明显降解，在大鼠大肠及其内容物和小肠及其内容物中发生明显降解，不受胃蛋白酶和胰蛋白酶的影响，受肠道菌群作用的影响。

Abstract:

OBJECTIVE To investigate the in vitro stability of timosaponin BⅡ in different physiological pH and biological sample.METHODS Timosaponin BⅡ was incubated in different phosphate buffer solutions with pH of 1.2, 6.8, 7.4 and 8.0, artificial gastrointestinal fluid, artificial gastrointestinal with no pepsin and trypsin and isolate biological media. The concentration of timosaponin B was determined Ⅱ by HPLC in order to investigate the degradation and the enzymatic stability of timosaponin B. ⅡRESULTS Timosaponin BⅡ was stable in pH 1.2, 6.8, 7.4 and 8.0, artificial gastrointestinal fluid, artificial gastrointestinal with no pepsin and trypsin within 9 h. Obvious degradation of timosaponin BⅡ was observed after incubationed in the large intestine and small intestine and their contents of isolated rats.CONCLUSION Timosaponin B is stable in Ⅱ simulated conditions of human stomach, intestines fluids, with no degradation and influence by pepsin and trypsin. But obvious degradation of timosaponin BⅡ is observed after incubationed in the large intestine and small intestine and their contents of isolated rats. Unaffected by pepsin and trypsin, it is affected by intestinal flora.