In Vitro Assessment of Picralima nitida Ethanol Leaf Extract's Ability to Inhibit alpha-Amylase and alpha-Glucosidase Enzymes.

Year 2025, Volume: 8 Issue: 2, 179 - 183, 23.12.2025

Okeke Chibuzor Okechukwu , Ikenna Nnaoma , Rich Joseph , Robinson Nwabueze Oguebie

https://doi.org/10.54565/jphcfum.1808963

https://izlik.org/JA75KX25CH

Abstract

This study investigated the in vitro α-amylase and α-glucosidase inhibitory activities of the n-hexane and chloroform fractions of Picralima nitida ethanol leaf extract, comparing them with acarbose, a standard antidiabetic drug. The assays were conducted at concentrations of 5, 10, 50, and 100 mg/mL to determine the dose-dependent inhibitory potential of each fraction. Results revealed that the n-hexane fraction exhibited a progressive, concentration-dependent inhibition of α-amylase activity, increasing from 47.88% at 5 mg/mL to 69.04% at 100 mg/mL. In contrast, the chloroform fraction displayed a non-linear pattern with inhibition ranging from 46.11% to 54.36%. Acarbose maintained consistently higher inhibition values (79.38–84.79%) across all concentrations. Similarly, α-glucosidase inhibition increased with concentration for both fractions, with the n-hexane fraction rising from 39.89% to 59.64% and the chloroform fraction showing a variable but moderate activity (56.55–64.04%). Acarbose again showed superior inhibition (78.46–82.30%) at all concentrations. The observed inhibitory effects suggest that P. nitida fractions possess bioactive constituents capable of modulating carbohydrate-hydrolysing enzymes in a dose-dependent manner. Although less potent than acarbose, the fractions demonstrate promising therapeutic potential for managing postprandial hyperglycemia.

Keywords

Picralima nitida , α-amylase inhibition , α-glucosidase inhibition , ethanol extract.

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