Development and validation of an efficient approach for extracting essential oil, scutellarin, and rosmarinic acid from Perilla frutescens leaves using vacuum microwave-mediated rotary hydrodistillation and extraction in situ and a choline amino acid ionic liquid

In this study, an efficient vacuum microwave-mediated rotary hydrodistillation and extraction in situ (VMRHDE) device was used for extracting essential oil, scutellarin, and rosmarinic acid from Perilla frutescens leaves with choline amino acid ionic liquid solution. The extracted products were then analyzed through GC–MS and HPLC. The optimal parameters were determined through a Doehlert design matrix and desirability function, resulting in the use of 10 % choline glutamate ionic liquid ([Ch][Glu]), a liquid–solid ratio of 15 mL/g, a microwave irradiation time of 20 min, a microwave irradiation power of 540 W, and a rotary speed of 24 r/min. Under optimal operating conditions, the yields of essential oil, scutellarin, and rosmarinic acid were 0.41 % ± 0.02 %, 0.39 % ± 0.01 %, and 0.36 % ± 0.01 %, respectively. GC–MS analysis revealed that adding [Ch][Glu] significantly increased the content of perilla aldehyde and oxygenates in the essential oils. Methodological validation confirmed that the established method met the detection requirements, with recoveries of 99.20 % for scutellarin and 99.83 % for rosmarinic acid, demonstrating high accuracy. The linear relationship of scutellarin and rosmarinic acid was good in the concentration range, with R2 values of 0.9999 for both.