The α-amylase and α-glucosidase inhibitory effects of some traditional antidiabetic prescriptions based on bioautography using LC-ESI/MSMS

Diabetes, one of the most common metabolic diseases in many societies, has influenced the quality of human life for many years. Traditional, alternative, and complementary medicine use individual or mixed plant prescriptions to reduce adverse consequences of diabetes. This is based on the human experience of treating and managing disease complications in different geographic areas, over a hundred years.

This research tries to find and recommend the most influential traditional medicine prescription for the inhibition of key enzymes associated with diabetes.

Considering the full and widespread use of the medicinal plants, in this research, 15 most reliable Iranian and Iraqi herbal prescriptions in controlling diabetes were studied for the inhibition of α-amylase and α-glucosidase enzymes. Chemicals of the most effective prescription for the inhibition of these enzymes were separated by using the HPTLC method. For chromatogram development, a mobile phase consisting of ethyl acetate: toluene: methanol: formic acid was used. A direct enzyme inhibitory assay on the HPTLC plate was used to investigate the most effective molecules. Thereafter, the influential molecules were identified by using LC-ESI/MSMS.

Based on the results, prescription No. 3, (from the Iraqi herbal prescription) containing the extract of Prunus mahaleb L. and Prunus dulcis (Mill.) D.A.Webb was identified as the best α-amylase and α-glucosidase inhibitor.

The chemical and molecular analysis of this extract which was performed by the HPTLC method and further by LC-ESI/MSMS, indicates two compounds of catechin and epicatechin.