Study of the volatilization rules of volatile oil and the sustained-release effect of volatile oil solidified by porous starch

Volatile oil from traditional Chinese medicine has various biological activities and has pharmacological activities in the central nervous system, digestive system, cardiovascular system, respiratory system, etc. These oils are widely used in clinical practice. However, the development of their clinical applications is restricted due to the disadvantages of volatile oils, such as high stimulation, high volatility and poor stability. To improve the stability of a volatile oil in the preparation process, its volatilization and stable release must be controlled. In this paper, porous starch was used as a solid carrier material, and liquid volatile oil was solidified by physical adsorption. GC–MS was used to determine the chemical constituents of the volatile oil, solidified powder and tablets, and the volatilization rules of 34 chemical constituents were analysed statistically. The solidified volatile oil/porous starch powder was characterized by XRD, TGA and DSC, and the VOCs of the volatile oil before and after solidification were analysed by portable GC–MS. Finally, the stable release of the volatile oil could be optimized by changing the porous starch ratio in the formulation. Volatilization was shown to be closely related to the peak retention time and chemical composition, which was consistent with the theory of flavour. The physical properties and chemical composition of the volatile oil did not change after curing, indicating that the adsorption of the volatile oil by porous starch was physical adsorption. In this paper, the porous starch-solidified volatile oil had a slow-release effect, and the production process is simple, easy to operate, and has high application value.