Phytochemical Profile and In Vitro α-Amylase and α-Glucosidase Inhibitory Activities of a 70 % Ethanol Extract of Green Apple (Malus Domestica Borkh) Fruits

Abstract

Malus domestica belong to (Family Rosaseae) have been reported to be widely consumed as a fruit and contains diverse bioactive phytochemicals with potential health-promoting activities. This study evaluated the phytochemical profile and inhibitory properties of in vitro α-amylase and α-Glucosidase using standard procedures. The plant material was extracted with 70% ethanol and subjected to qualitative and quantitative phytochemical analysis using standard procedures. The inhibitory activities against α-amylase and α-glucosidase were evaluated at concentrations of 62.5–1000 µg/mL, using acarbose as the reference inhibitor, and IC₅₀ were determined. Qualitative phytochemical screening revealed the presence of alkaloids, flavonoids, terpenoids, tannins, and glycosides. The extract had a total phenolic content of 116.699 ± 0.493 mg GAE/g extract and a total flavonoid content of 24.063 ± 0.071 mg CE/g extract. The α-amylase inhibitory activity of the extract increased from 28.989 ± 0.978% at 62.5 µg/mL to 84.201 ± 0.261% at 1000 µg/mL, compared with 88.190 ± 0.208% and 90.181 ± 0.128%, respectively, for acarbose. The IC₅₀ values were 159.600 µg/mL for the extract and <62.5 µg/mL for acarbose, indicating greater α-amylase inhibitory potency of the reference inhibitor. For α-glucosidase, the extract produced inhibition values ranging from 36.758 ± 15.453% to 56.238 ± 3.932% across the tested concentration range, while acarbose produced inhibition values ranging from 46.335 ± 4.580% to 56.475 ± 2.416%. The corresponding IC₅₀ values were 124.020 µg/mL for the extract and 143.715 µg/mL for acarbose.