Potent In Vitro α-Glucosidase and β-Secretase Inhibition of Amyrin-Type Triterpenoid Isolated from Datura metel Linnaeus (Angel's Trumpet) Fruits

This study deals with α-glucosidase and β-secretase inhibitory screening of extract/fractions and isolated daturaolone (1), namely, 3-oxo-6-β-hydroxy-β-amyrin (daturaolone) from chloroform fraction of Datura metel L. Among entire fractions, the chloroform soluble fraction showed excellent activity against α-glucosidase with % inhibition 90.8 with IC(50)160.2 ± 1.85 μg and daturaolone (1) with 98.7% inhibition with IC(50)840.4 ± 1.74 μM, respectively. Similarly, extract and daturaolone (1) also exhibited significant activity against the β-secretase enzyme (BACE1) with % activities 88.27 and 95.19 and with IC(50) values 304.21 ± 2.98 μg and 260.70 ± 1.87 μM, respectively, as compared to the standard inhibitor (Ans670, Sta671, Val672)-amyloid-β/A4 precursor protein 770 fragments 662-675) with % activity 94.21 and IC(50) value 289.24 ± 1.60 μM. This finding encourages and opens a new window for further detail phytochemical investigation on D. metel in order to isolate novel compounds with promising enzyme inhibitory potential.