响应面优化高速剪切法制备薄荷挥发油包合物工艺

Preparation of Peppermint Oil/β-CD Inclusion by High-speed Shearing with Process Optimization Using Response Surface Methodology

目的:考察高速剪切结合冷冻干燥法制备薄荷挥发油的β-环糊精(β-cyclodextrin,β-CD)包合物的最佳工艺。方法:对比冷冻干燥与真空干燥,高速剪切与搅拌法对包合工艺的影响;在单因素实验基础上,以β-CD与挥发油的比例、包合温度和β-CD的质量分数为影响因素,以含油率和包合率的综合评分为评价指标,考察Box-Behnken响应面法优化的包合工艺;采用高效液相色谱(high performance liquid chromatography,HPLC)测包合物中的胡薄荷酮含量;傅里叶变换红外光谱(fouriertransforminfrared spectroscopy,FTIR)对包合物进行表征。结果:冷冻干燥法制备的包合物收率更高,平均收率为97.6%。高速剪切法制备的含油率和包合率较高,与搅拌法相比分别高出约3%和19%;包合物的最佳制备条件为:β-CD与挥发油比例为9:1(g/mL),包合温度为55℃,β-CD的质量分数为17%。在此条件下,挥发油含油率为10.9%,挥发油包合率为97.6%,综合评分为99.7,RSD值为1.59%,优化的工艺稳定可行;通过HPLC测得包合物中胡薄荷酮含量为2.465 mg/g;FTIR分析证明了薄荷油-β-CD包合物的形成。结论:高速剪切和冷冻干燥法结合制备薄荷挥发油包合物效率高,工序简便,提高了收率,对生产工艺有指导作用。

Objective:To investigate the optimal process for preparing peppermint essential oil/β-cyclodextrin(β-CD)inclusion complex using high-speed shearing combined with freeze-drying.Methods:The effects of freeze-drying and vacuum drying,high-speed shearing,and stirring on the encapsulation process were compared.Based on single-factor experiments,the ratio ofβ-CD to essential oil,encapsulation temperature,and mass fraction ofβ-CD were considered as influencing factors.The comprehensive score of oil content and encapsulation efficiency was used as an evaluation index to investigate the Box-Behnken response surface method for optimizing the encapsulation process.The content of pulegone in the inclusion complex was measured by high-performance liquid chromatography(HPLC).Fourier transform infrared spectroscopy(FTIR)was used to characterize the inclusion complex.Results:The yield of inclusion complex prepared by freeze-drying was higher,with an average yield of 97.6%.The oil content and encapsulation efficiency by the high-speed shearing method were relatively high,being about 3%and 19%higher than those by the stirring method,respectively.The optimized conditions were as follows:The weight ratio ofβ-CD to volatile oil was 9:1(g/mL),the encapsulation temperature was 55℃,and the mass fraction ofβ-CD was 17%.Under these conditions,the essential oil content was 10.9%,the encapsulation efficiency was 97.6%,the comprehensive score was 99.7,the RSD value was 1.59%,and the optimized process was stable and feasible.The content of pulegone in the inclusion complex was found to be 2.465 mg/g by HPLC.The formation of the peppermint oil/β-CD inclusion complex was confirmed by analysis using FTIR.Conclusion:The combination of high-speed shearing and freeze-drying for the preparation of peppermint essential oil inclusion complex had the advantages of high efficiency,simple process,and it improved the yield,would provide guidance for the production process.