In sight on olive oil maceration and supercritical CO₂ in extracting rosemary essential oil

The flavor, nutritional, and medicinal value of rosemary are well known. Hydrodistilled (HD) essential oil was prepared in the present study as a standard. Olive oil maceration (OM) and supercritical carbon dioxide (SC-CO₂) technology were separately applied to extract the essential oil of rosemary. The three obtained products, HD, OM, and SC-CO₂, were compared concerning their main constituents using GC‒MS. Their antimicrobial properties were evaluated against eight microbes by the disc diffusion assay. Interestingly, both 1,8-cineol and camphor were the major compounds in the three oils. α-Pinene was also detected in large amounts in both HD and OM. Additionally, borneol was the third major component in SC-CO₂. The antimicrobial results revealed differential effects against six microbes. However, HD oil also exhibited antifungal activity. Maceration is a green extraction procedure that is easy to perform in households, and attention must be paid to olive oil maceration as a complementary medicine that originated in pharaohs.