Alfa-amylase inhibitors are used to reduce glucose absorption by suppressing carbohydrate digestion. The current study aimed to evaluate seven wild edible Palestinian plants' hydrophilic and lipophilic fractions against porcine pancreatic α-amylase enzyme. The lipophilic fractions of Arum palaestinum, Malva sylvestris, Plantago major, Centaurea iberica, Cichorium endivia, Bituminaria bituminosa, Sisymbrium irio leaves were sequentially separated with a nonpolar solvent hexane, while the hydrophilic fractions of the studied plants were separated with polar solvents ethanol and water. The activity of α-amylase inhibition was carried out by using α-amylase porcine pancreatic enzyme and 3,5-dinitrosalicylic acid (DNSA) method as well as by using Acarbose as a positive control. Among the studied plant's hydrophilic fractions, C. iberica and C. endivia have the highest porcine pancreatic α-amylase inhibitory effect with an IC50 value of 12.33 µg/mL and 9.96 µg/mL, respectively. In addition, among the studied plant's lipophilic fractions, S. irio and A. palaestinum have the highest porcine pancreatic α-amylase inhibitory effect with an IC50 value of 7.72 µg/mL and 25.3 µg/mL, respectively. In fact, these revealed results were near the values of Acarbose. The hydrophilic fractions of M. sylvestris and the lipophilic fractions of P. major plants exhibit remarkable α-amylase inhibitory activity. Hence, these leaves have a potential for use as regular supplements also; further investigations are required to isolate pure pharmacological molecules and to design suitable pharmaceutical dosage forms with anti-diabetic activity.
Keywords: Palestine; hydrophilic fraction; lipophilic fraction; wild plants; α-amylase.