Phytochemical Screening and Antioxidant Potential of Selected Extracts from Betula alba var. pendula Roth., Glycyrrhiza glabra L., and Avena sativa L.

The aim of the present study was to obtain, characterize, and evaluate the antioxidant potential of some extracts obtained from the bark of Betula alba var. pendula Roth., the root of Glycyrrhiza glabra L., and the green herb of the Avena sativa. The results revealed that the lowest IC50 value, determined by all three methods, was obtained for Betulae extractum (BE) (73.6 & mu;g/mL-DPPH method, 11.2 & mu;g/mL-ABTS method, and 58.7 & mu;g/mL-FRAP method), followed by Liquiritiae extractum (LE) (805.6 & mu;g/mL, 92.1 & mu;g/mL, and 722 & mu;g/mL) and Avenae extractum (1.13 mg/mL-DPPH method, 99.7 & mu;g/mL-ABTS method, and 135.1 & mu;g/mL-FRAP method). These results correlate with total polyphenols content (expressed in g tannic acid/100 g dry extract), with BE having more polyphenols than LE and AE (47.96 & PLUSMN; 9.7083 for BE, compared with 9.31 & PLUSMN; 0.9913 for LE and 40.55 & PLUSMN; 6.3715 for AE). The total flavonoid content (expressed as g rutoside/100 g dry extract) is similar for BE and LE (3.75 & PLUSMN; 0.3140 and 3.44 & PLUSMN; 0.3037) and smaller for AE (1.95 & PLUSMN; 0.0526). Therefore, Betulae extractum has the strongest antioxidant action, with an IC50 value very close to the standard used as a reference (ascorbic acid-16.5 & mu;g/mL solution). The FT-ICR-MS analysis confirmed the presence of the major compounds in all three extracts. The antioxidant properties of the studied extracts were further supported by molecular docking experiments that revealed the potential of the analyzed phytochemicals to act as both noncovalent and covalent activators of the Nrf2 signaling pathway, with promising benefits in treating various skin disorders.

Automated summary

The aim of this study was to obtain, characterize, and evaluate the antioxidant potential of extracts from three different plant sources. The results showed that the extract from Betula alba var. pendula Roth. had the strongest antioxidant action, followed by extracts from Glycyrrhiza glabra L. and Avena sativa. The total polyphenols content and total flavonoid content correlated with the antioxidant activity of the extracts. Molecular docking experiments revealed the potential of the analyzed phytochemicals to activate the Nrf2 signaling pathway, which could be beneficial in treating various skin disorders.