Network analysis, chemical characterization, antioxidant and enzyme inhibitory effects of foxglove (Digitalis cariensis Boiss. ex Jaub. & Spach): A novel raw material for pharmaceutical applications

The present study outlines the phenolic composition and pharmacological properties of different extractsof Digitalis cariensis Boiss. ex Jaub. & Spach root and aerial parts. The metabolic profiles of the studiedextracts were characterized by UHPLC-MS. The in vitro antioxidant and enzyme (acetylcholinesterase(AChE), butyrylcholinesterase (BChE), tyrosinase, -amylase, and -glucosidase) inhibitory potential ofthe extracts were determined. Bioinformatics and docking investigations were also conducted to supportthe enzyme inhibition test and predict putative targets for potential pharmacological applications. Over-all, the methanolic extract followed by the water extract of the D. cariensis root were found to be superiorsource of antioxidant compounds except for metal chelating ability, in which the water extract of the root(26.34 ± 1.54 mg EDTAE/g) and aerial parts (16.47 ± 0.88 mg EDTAE/g) have showed the highest activity.The tested extracts were potent against AChE (9.11 ± 0.27–9.79 ± 0.28 mg GEs/g extract), -amylase(0.12 ± 0.01- 0.50 ± 0.01 mmol ACEs/g extract) and -glucosidase (0.28 ± 0.01–17.29 ± 0.24 mmol ACEs/g extract). Notable activity against tyrosinase was displayed by the methanolic extracts (Root-MeOH:123.71 ± 2.70 and aerial parts - MeOH: 137.96 ± 1.07 mg KAE/g extract), while none of the extractswere potent against BChE. According to docking investigations, the observed anti-tyrosinase effect couldbe related, at least partially, to the presence of luteolin, rosmarinic acid and kaempferol in the extracts.Results amassed herein is the first report on the biological attributes of D. cariensis, which validate thepharmacological uses of this plant.