火龙果茎中3种主要甾醇的提取工艺研究

Study on the Extraction Technology of Three Main Sterols from the Pitaya Stem

以火龙果茎为原料,采用超声波辅助萃取法提取火龙果茎中3种主要甾醇(麦角甾醇、豆甾醇、β-谷甾醇),并利用高效液相法对提取的3种甾醇含量进行分析。在单因素实验的基础上,利用响应面分析法对提取工艺进行优化。结果表明,影响火龙果茎甾醇含量的因素是超声提取温度>超声提取时间>液固比,最优工艺为:以95%乙醇为提取溶剂,超声功率100 W,超声提取温度53.61℃、超声提取时间168.45 min、液固比17.10∶1,实验预测综合评分为2.3743。依据最优工艺条件进行验证实验,得到最优工艺条件下火龙果茎甾醇含量为:麦角甾醇含量为179.08 mg/hg,豆甾醇含量为156.02 mg/hg,β-谷甾醇含量为54.89 mg/hg,总甾醇含量为389.99 mg/hg。综合评分为2.3633,这与理论综合评分2.3743相比无显著性差异。因此采用Box-Behnken实验设计优化得到的甾醇提取工艺准确可靠。

Three main phytosterols(ergosterol,stigmasterol,β-sitosterol)were extracted from the pitaya stem by ultrasonic assisted extraction.The content of three main sterols were analyzed by HPLC.In addition,the response surface analysis were used to optimize the extraction of three main sterols based on the results of single factor experiments.The results showed that the affecting factors of the content of sterols were ultrasonic extraction temperature>ultrasonic extraction time>liquid-solid ratio.The optimal process was as follows:95%ethanol was used as extraction solvent,the ultrasonic power was 100W,the ultrasonic extraction temperature was 53.61℃,the ultrasonic extraction time was 168.45min,the liquid-solid ratio was 17.10:1,and the comprehensive score of test prediction was 2.3743.According to the optimal process conditions,the results showed that the sterol content of pitaya stem was as follows:the content of ergosterol was 179.08 mg/hg,the content of stigmasterol was 156.02 mg/hg,the content ofβ-sitosterol was 54.89 mg/hg,the content of total sterol was 389.99 mg/hg.The comprehensive score was 2.3633,which was not significantly different from the theoretical comprehensive score of 2.3743.Therefore,the sterol extraction process optimized by Box-Behnken test design was accurate and reliable.