Phenolics from strawberry cv. Falandi and their antioxidant and α-glucosidase inhibitory activities.

Three new phenolic glucosides, falandiosides A ( 1 ), B ( 2 ), and C ( 6 ) were isolated from strawberry ( Fragaria × ananassa Duch.) cv. Falandi fruit, together with three flavone glucuronides ( 3 – 5 ), eleven lignan glycosides ( 12 – 22 ), and five others. Their structures were determined by spectroscopic methods. All the known phenolics were reported from strawberry for the first time. They were evaluated for antioxidant and α-glucosidase inhibitory activities. Three new and fifteen known phenolics showed potent 2,2′-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical cation scavenging activity with IC 50 values of 22.50–4.28 μM in comparison to l -ascorbic acid (14.21 μM). Quercetin 3-(6-methylglucuronide) ( 4 ), (+)-isolariciresinol 9′-glucoside ( 12 ), and (−)-isolariciresinol 9′-glucoside ( 13 ) were active in scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. Moreover, compounds 12 and 13 had moderate ferric reducing antioxidant power (FRAP) values. Further, two new and seven known phenolics exhibited more potent α-glucosidase inhibitory activity with IC 50 values of 537.43–25.39 μM than acarbose (619.94 μM). [ABSTRACT FROM AUTHOR]