Dudai, N., Aromatic, Medicinal and Spice Crops Unit ARO, Newe Ya'ar Research Center, Ramat Yishay 30095, Israel
Fischer, R., Aromatic, Medicinal and Spice Crops Unit ARO, Newe Ya'ar Research Center, Ramat Yishay 30095, Israel
Segev, D., Aromatic, Medicinal and Spice Crops Unit ARO, Newe Ya'ar Research Center, Ramat Yishay 30095, Israel
Chaimovitsh, D., Aromatic, Medicinal and Spice Crops Unit ARO, Newe Ya'ar Research Center, Ramat Yishay 30095, Israel
Rosenzweig, N., Biotechnology Department, Ort Braude College, Karmi'el, Israel
Shimoni, M., Biotechnology Department, Ort Braude College, Karmi'el, Israel

Catha edulis Forsk. (khat) is an evergreen tree growing wild in high altitudes in East Africa and the Arabian Peninsula. Due to its stimulating effect, chewing fresh young leaves of khat has become a common habit in several countries in those regions, which later spread to the Western world. The stimulating activity of khat is attributed to its alkaloid fraction, comprising mainly of cathine and cathinone. In addition to its everyday use , khat has been known as a traditional medicinal plant for centuries. Therefore, additional aspects concerning this species secondary metabolism and its related biological activity are currently examined. In an attempt to identify new potential plant sources for antioxidants, khat varieties were found to posses a substantial antioxidative activity, ranging 175-204 mg/g DW chlorogenic acid equivalent. Cathine and cathinone were found to have a negligible contribution to the antioxidative activity. In order to estimate the potential use of Catha edulis as a natural antioxidant source, further aspects such as plant material availability, extraction efficiency and safety issues are yet to be evaluated.