1. a Department of Phytochemistry and Plant Systematics , National Research Centre , El Tahrir Street, Dokki 12311 , Cairo , Egypt
2. b Department of Pharmacognosy , Faculty of Pharmacy, Al Azhar University , Nasr City 1137 , Cairo , Egypt
3. c Department of Pharmacognosy , National Research Centre , El Tahrir Street, Dokki 12311 , Cairo , Egypt