Background: Fruit wines are well known for their profound health-promoting properties including
both enzyme activations and inhibitions. They may act preventive in regard to diabetes melitus
and other chronic diseases.
Objectives: Potential α-glucosidase inhibitory activity of fruit wines made from blueberry, black
chokeberry, blackberry, raspberry and sour cherry was the subject of this study.
Method: In order to increase the alcohol content due to enriched extraction of total phenolics, sugar
was added in the fruit pomace of the half of the examined fruit wine samples.
Results: Compared with acarbose used as a positive control (IC50 = 73.78 µg/mL), all fruit wine
samples exhibited higher α-glucosidase inhibitory activity. Indeed, blueberry wine samples stood out,
both prepared with IC50 = 24.14 µg/mL, lyophilised extract yield 3.23% and without IC50 = 46.39
µg/mL, lyophilised extract yield 2.89% and with addition of sugar before fermentation. Chlorogenic
acid predominantly contributed to α-glucosidase inhibitory activity of the blueberry, black chokeberry
and sour cherry wine samples. However, ellagic acid, a potent α-glucosidase inhibitor possessing a
planar structure, only slightly affected the activity of the blueberry wine samples, due to the lower
concentration. In addition to this, molecular docking study of chlorogenic acid pointed out the
importance of binding energy (-8.5 kcal/mol) for the inhibition of the enzyme.
Conclusion: In summary, fruit wines made from blueberry should be primarily taken into
consideration as a medicinal food targeting diabetes mellitus type 2 in the early stage, if additional
studies would confirm their therapeutic potential for the control of postprandial hyperglycemia.