水蒸气蒸馏法提取小茴香挥发油类成分的提取动力学研究

目的通过气相色谱-质谱联用(GC-MS)技术分析,揭示小茴香挥发油提取过程中的成分溶出规律。方法采用水蒸气蒸馏法提取小茴香挥发油,固定时间间隔(30 min)收集挥发油/芳香水体系,分离挥发油部分和芳香水部分,选取正二十二烷和肉豆蔻酸甲酯为双内标物进行GC-MS分析并定量。通过热图分析提取主要特征成分,并明确成分分布规律,结合化合物相对分子质量、熔点、沸点、密度等物理化学性质考察影响成分分布的主成分。结果 GC-MS共解析挥发性成分123个,其中主要成分为草蒿脑、茴香脑及(R)-(+)-柠檬烯;芳香水溶液中特有成分60种,挥发油特有成分36种,27种成分为油水共有成分。水中特有成分与芳香水中主要成分茴香脑的含量呈正相关关系,进一步与草蒿脑及(R)-(+)-柠檬烯含量呈正相关,油中特有成分与挥发油中主要成分(R)-(+)-柠檬烯含量呈正相关;主成分分析结果表明,化合物的理化性质是影响成分分布的重要因素,PC1(相对分子质量、熔沸点正相关)、PC2(折射率正相关)以及PC3(水溶性负相关)是导致成分分布差异的主成分。结论水蒸气蒸馏法提取小茴香挥发油过程中,受挥发性成分自身理化性质的影响,部分成分特异性地在芳香水、挥发油体系分布,芳香水中特有成分增加了主要成分在水部分中的含量,可能是导致挥发油提取过程中产生"乳化"现象、降低挥发油收率及质量的重要原因。

Extraction kinetics of volatile components from Foeniculum vulgare by steam distillation

Objective To reveal the dissolution rule of volatile oil in the extraction processfrom Foeniculum vulgare by GC-MS analysis. Methods The volatile oil of F. vulgare was extracted by steam distillation; The volatile oil/perfume system was collected at fixed time interval (30 min); The volatile oil part and perfume part were separated. Using N-docosane and methyl myrisate as double internal standard, GC-MS was selected for analysis and quantification. The main components were extracted by thermography, and the distribution regularity of components was definited. The principal components with the impact on the composition distribution were investigated according to the physical and chemical properties of the molecular weight, melting point, boiling point, and density of the compounds. Results The GC-MS analysis results concluded 123 volatile components. The main components were estragole, anethole, and (R)-(+)-limonene. There were 60 and 27 endemic components in aromatic aqueous solution and volatile oil, respectively, in which 27were common composition. The content of anethole in water was positively related to the endemic components in aromatic water, and even had a positive correlation with anethole artemisia content and (R)-(+)-limonene content. The specific components in the oil were positively related to the content of the main components (R)-(+)-limonene in the volatile oil. The principal component analysis showed that the physical and chemical properties of the compounds were important factors affecting the distribution of components; PC1 (molecular weight and positive correlation of melting point), PC2 (refractive index positive correlation), and PC3 (water-soluble negative correlation) were the principal components that lead to differences in component distribution. Conclusion In the process of extracting volatile oil from F. vulgare, steam distillation is affected by the physical and chemical properties of volatile components. Some components are specifically distributed in aromatic perfume and volatile oil system. The endemic components of aromatic water increase the content of the main components in the water system, which may lead to theproduction of "emulsification" during the extraction process of volatile oil and reduce the yield and quality of volatile oil.