Abstract
Thirteen plant species which are claimed to have anti-diabetic activity (based on folk medicine and/or scientific reports) were tested for alpha amylase inhibitory activity. Two of the screened plants exhibited significant (more than 80%) alpha amylase inhibitory activity. lC50 of these plants was estimated based on the dried crude extract and found to be 0.08, and 0.2 mg/ml for Aloe vera and Paronychia argentea respectively. In A. vera the activity was most likely due to cinnamic acid derivatives. In P. argentea the activity was attributed to flavonoid components. These findings support the hypoglycemic activity of these species and give insight about the potential mechanism of their hypoglycemic activity.