Berry components inhibit α-glucosidase in vitro: Synergies between acarbose and polyphenols from black currant and rowanberry

► Polyphenol-rich extracts from berries potently inhibited α-glucosidase activity in vitro. ► The extracts acted synergistically with the pharmaceutical glucosidase inhibitor, acarbose. ► The phenolic components may find use as nutracueticals for blood glucose control in type 2 diabetics.