Angiotensin I-converting Enzyme (ACE) Inhibitory Activity and Chemical Composition of Alchemilla Viridiflora Rothm.

Abstract Alchemilla viridiflora Rothm., Rosaceae is a herbaceous plant widespread in central Greece, Bulgaria, North Macedonia and Serbia with Kosovo. LC-MS analysis leads to the identification of 20 compounds in methanol extract, mainly ellagitannins and flavonoid glycosides. Considering that different plant extracts were traditionally used for treatment of hypertension and that some of the analyzed methanol extract constituents possess beneficial cardiovascular effects, we hypothesized that some of these effects are achieved through inhibition of angiotensin I-converting enzyme (ACE). The dose-dependent activities ACE inhibitory activity of A. viridiflora and miquelianin were observed with an IC50 of 2.51 ± 0.00 µg/ml of A. viridiflora compared to IC50 of 2.59 ± 0.00 µg/mL for miquelianin. Contribution of the single compounds to the tested activity was further analyzed through the in silico experimental approach. Computational docking results showed that tiliroside, ellagic acid pentose and galloyl-HHDP-glucose exhibited even better binding affinity for ACE active site than miquelianin, which ACE activity was confirmed by an in vitro assay.