Hypoglycemic, Antiglycation and Cytoprotective Properties of A Phenol Rich Extract from Waste Peel of Punica Granatum L. Var. Dente Di Cavallo DC2

Pomegranate peel is a natural source of phenolics, claimed to possess healing properties, among which antioxidant and antidiabetic. In line with this evidence, the ethyl acetate PGE extract, obtained by Soxhlet from the peel of Dente di cavallo DC2 variety and characterized by a 4% amount of ellagic acid, has been studied for its hypoglycemic, antiglycation and antioxidative cytoprotective properties, in order to support a possible further nutraceutical interest. The α-amylase and α-glucosidase enzyme inhibition, interference with advanced glycation end-products (AGE) formation and metal chelating abilities were evaluated as hypoglycemic mechanisms. Also, considering that oxidative stress is associated with hyperglycemia complications, PGE antioxidant cytoprotective properties under hyperglycemic conditions were assayed. Phenolic profile was characterized by integrated chromatographic and spectrophotometric methods. Under our experimental conditions, PGE strongly inhibited the tested enzymes, especially α-glucosidase, and exerted chelating and antiglycation properties. Also, it reduced both ROS and GSH levels under hyperglycemic conditions, thus suggesting its ability to support cell functions by counteracting intracellular oxidative stress. Along with ellagic acid, rutin was the major identified flavonoid (about 4 %) of PGE. Present results suggest PGE to be a possible remedy for hyperglycemia management and encourage further studies to exploit its promising properties.