Evaluation of Antioxidant, Anticholinesterase, and Antidiabetic Potential of Dry Leaves and Stems in Tamarix aphylla Growing Wild in Tunisia

Tamarix aphylla (L.) KARST. has a wide geographic distribution and was employed in traditional medicine as astringent, anti-rheumatic and to treat fever. T. aphylla leaves and stems extracts were studied from both chemical and biological points of view to assess the antidiabetic, anticholinesterase and antioxidant potential of this species. The HPLC/Diode Array Detector (DAD) analysis showed the presence of 14 phenolic compounds (gallic, caffeic, p-coumaric, ferulic and ellagic acids, kaempferol, quercetin, quercetin 3-O-galactoside and six flavonol derivatives). This is the first study reporting a comparative study of the biological activities of different extracts from T. aphylla. High activities were obtained against DPPH radical, superoxide anion radical (O-2(center dot-)) and nitric oxide radical ((NO)-N-center dot) in a concentration-dependent manner, the most active extracts being the polar ones. T. aphylla also showed moderate protective effects against acetylcholinesterase, but no effects were observed against butyrylcholinesterase. Against a-glucosidase the MeOH extracts displayed IC50 values from 8.41 to 24.81 mu g/ml.