Oil-water distribution characteristics of volatile oil from Dalbergiae Odoriferae Lignum by steam distillation / 中草药

ABSTRACT

Objective: To reveal the extraction, distribution, and influencing factors of volatile components in the extraction process of Dalbergiae Odoriferae Lignum (DOL). Methods: Volatile oil was extracted by steam distillation, and the extract was collected every 30 min to separate the aromatic water part and the volatile oil part, of which chemical composition was analyzed by GC-MS. Results: A total of 136 volatile constituents were obtained, of which trans-nerolidol, (E)-β-famesene, and α-farnesene were the main characteristic constituents. A total of 22 kinds of components distributed only in water, 13 kinds only in oil and 101 kinds in both oil and water. The specific components in water were positively correlated with the dissolution/diffusion of the main characteristic components in aromatic water, while negatively correlated with the main components in volatile oil. The water solubility of the unique components in water is the highest. The results of principal component analysis showed that PC1 (melting point, surface tension, polar surface, negative correlation of refractive index) and PC2 (polarizability, molecular weight, boiling point positive correlation, negative correlation of water solubility) were the principal components that lead to the difference of component distribution. Conclusion: Affected by the physical and chemical properties of volatile component itself, some components specifically distributed in water which increased the content of main components in the aromatic water, resulting in volatile oil extraction process easy to “emulsification”, in turn, leading to an important reason for the declining quality of volatile oil.