Rosemary is well known as a spice and widely used plant in ethnomedicine worldwide. In this paper,
commercial essential oil of rosemary was tested for antimicrobial and cytotoxic activity together with its
effect on germination. Antimicrobial activity testing showed moderate effect to both G-positive and Gnegative
bacteria. In order to determine its effect to the cell membrane, spectrophotometric analysis was
performed. It was determined that rosemary affects the cell membrane of bacteria. Cytotoxic activity of
Rosmarinus officinalis essential oil had been evaluated. As a plant object, germinative bulbs of Allium cepa
were used. Cytotoxic activity that corresponded to the concentration of essential oil was determined. It had
been noticed that rosemary essential oil affected mitotic phase i.e. it significantly slowed down the mitosis.
Also, investigation of rosemary essential oil's activity to germination was performed. It was determined that
it had high effect to the germination. Concentration of 5 mg/ml completely inhibited the germination of
Triticum vulgare