Intensification of Hypericum perforatum L. oil isolation by solvent-free microwave extraction

- Microwave extraction technique was used to isolate oil from Hypericum perforatum L.
- Influence of irradiation power, time and moisture content were evaluated by RSM.
- The antioxidant capacity of obtained oil was investigated by DPPH and FRAP assays.
- SFME showed obvious advantages in terms of high extraction efficiency.
- SFME have a high antioxidant activity compared to hydrodistillation.