title: A comparative study on the inhibitory effects of different parts and chemical constituents of pomegranate on α-amylase and α-glucosidase.
abstract: Pomegranate has been documented for the management of diabetes in Unani and Chinese medicine. This study compared the effects of the extracts of different pomegranate parts, including juice, peels, seeds and flowers, on carbohydrate digestive enzymes (α-amylase and α-glucosidase) in vitro. The methanolic flower extract inhibited α-amylase and α-glucosidase, while the methanolic peel extract inhibited α-glucosidase selectively. The most active flower extract was subjected to water-ethyl acetate partition. The ethyl acetate fraction was more potent than the water fraction in inhibiting both enzymes. Gallic acid and ellagic acid also showed selective inhibition against α-glucosidase, and their presence in the ethyl acetate fraction was confirmed by HPLC-DAD and HPLC-HESI-MS. Our findings suggest that the inhibition of carbohydrate digestive enzymes and their phenolic content may contribute to the anti-hyperglycaemic effects of pomegranate flower and peel, and support their claims in diabetes.
authors.affiliation: Faculty of Pharmacy, University of Sydney, NSW 2006, Australia.
authors.forename: Antony
authors.initials: A
authors.lastname: Kam
authors.forename: Kong M
authors.initials: KM
authors.lastname: Li
authors.forename: Valentina
authors.initials: V
authors.lastname: Razmovski-Naumovski
authors.forename: Srinivas
authors.initials: S
authors.lastname: Nammi
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Shi
authors.forename: Kelvin
authors.initials: K
authors.lastname: Chan
authors.forename: George Q
authors.initials: GQ
authors.lastname: Li
mesh_terms: D000818:Animals; D004610:Ellagic Acid / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D035264:Flowers / Q000737:chemistry; D005638:Fruit / Q000737:chemistry; D005707:Gallic Acid / Q000494:pharmacology; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents / Q000737:chemistry / Q000494:pharmacology; D029561:Lythraceae / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D012639:Seeds / Q000737:chemistry; D013552:Swine; D000516:alpha-Amylases / Q000037:antagonists & inhibitors*
chemical_list: D004791:Enzyme Inhibitors; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents; D010936:Plant Extracts; D004610:Ellagic Acid; D005707:Gallic Acid; D000516:alpha-Amylases
keywords: Punica granatum; diabetes; pomegranate; α-amylase; α-glucosidase