Isolation and Biological Evaluation of Prenylated Flavonoids from Maclura pomifera

摘要

Phytochemical analysis of the ethanolic extract of Maclura pomifera fruits yielded four new compounds (>I–>IV) along with eleven known compounds (>V–>XV). The crude extract exhibited significant activity towards cannabinoid receptors (CB1: 103.4% displacement; CB2: 68.8% displacement) and possibly allosteric interaction with δ and μ opioid receptors (−49.7 and −53.8% displacement, resp.). Compound> I was found to be possibly allosteric for κ and μ opioid receptors (−88.4 and −27.2% displacement, resp.) and showed moderate activity (60.5% displacement) towards CB1 receptor. Compound> II exhibited moderate activity towards cannabinoid receptors CB1 and CB2 (47.9 and 42.3% displacement, resp.). The known compounds (>V–>VIII) exhibited prominent activity towards cannabinoid receptors: pomiferin (>V) (IC50 of 2.110 and 1.318 μM for CB1 and CB2, resp.), auriculasin (>VI) (IC50 of 8.923 μM for CB1), warangalone (>VII) (IC50 of 1.670 and 4.438 μM for CB1 and CB2, resp.), and osajin (>VIII) (IC50 of 3.859 and 7.646 μM for CB1 and CB2, resp.). The isolated compounds were also tested for inhibition of human monoamine oxidase-A and monoamine oxidase-B enzymes activities, where all the tested compounds showed fewer inhibitory effects on MAO-A compared to MAO-B activities: auriculasin (>VI) (IC50 of 1.91 and 45.98 μM for MAO-B and MAO-A, resp.).