The effect of harvest time on the natural product of Rosmarinus officinalis L. from South Iran (Fars province).

The medicinal composition of rosemary essential oil has led to its widespread use in the food, cosmetic, health and herbal industries. In the present work, seasonal variations of essential constituents of essential oil, essential oil yield were evaluated. The predominant components of rosemary were: camphene, limonene, α-pinene, camphor, borneol, linalool, 1,8-cineole, (E)- caryophyllene and bornyl acetate. The highest rate of linalool was seen in summer, while camphor, limonene and borneol showed the highest percentage in cold season. Some of the compounds such as α-pinene, camphene, bornyl acetate and (E)- caryophyllene in the spring with the activation of some important plant enzymes such as peroxidase showed the highest amount. It is hoped that this research will provide very useful information about the best time to harvest the valuable rosemary plant and can be useful for the health, food and herbal industries that use this plant.