Phytochemical composition, antioxidant, enzyme inhibition, antimicrobial effects, and molecular docking studies of Centaurea sivasica

In this study, Centaurea sivasica Wageitz (Asteraceae) methanol extract was examined regarding phytochemical composition, in vitro antioxidant properties, ability to inhibit tyrosinase, alpha-amylase, alpha-glucosidase enzymes, and antimicrobial effects. Also, possible binding and interactions of phytochemicals with enzymes by molecular docking were determined. The extract's phenolic amount was 21.42 mg GAE/g extract, and the extract was determined to be rich in flavonoids (19.73 mg RE/g extract). Due to the results of liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) analysis, the main components of the methanol extract was scutellarin (27843.91 mu g/g), quercimeritrin (3629.85 mu g/g), chlorogenic acid (2519.68 mu g/g) and baicalin (920.49 mu g/g). The methanol extract was found to show remarkable activity in all antioxidant activity tests and had a high potential to inhibit the enzymes examined. The extract was radical scavenging on (DPPH and ABTS), reducing power (FRAP and CUPRAC), phosphomolybdenum assays were measured as 2.72, 69.58, 44.78, 141.18, 109.25 mg TE/g extract, respectively. Tyrosinase, alpha-amylase, and alpha-glucosidase inhibitory activities were 36.81 mg KE/g extract, 252.60 and 279.40 mg AKE/g extract, respectively. Scutellarin inhibited the tyrosinase enzyme very effectively, and its effect was found as 43.32 mu M or 20.38 mu g/mL. The extract showed different inhibition zones (16.3, 16.0, 15.0, 15.6 mm) and MIC values (500-1000 mu g/mL) on the microorganisms examined (B. cereus, S. aureus, E. coli, C. albicans). In molecular docking studies, the most abundant scutellarin in the extract was shown to affect both tyrosinase and alpha-glucosidase inhibition significantly. (C) 2021 SAAB. Published by Elsevier B.V. All rights reserved.