Polyphenolic-rich extracts from the leaves of Ilex paraguariensis and Larrea divaricata and their antioxidant and antiCOVID-19 potential

Abstract

Yerba mate (Ilex paraguariensis A.St. Hil) and jarilla (Larrea divaricata Cav.) leaves are commonly used as tea infusions in some Latin American countries. This study was conducted to evaluate the antioxidant activity (FRAP, ABTS, and DPPH) and the inhibitory potential of yerba mate and jarilla extracts on the 3CL protease (Mpro) from coronavirus SARS-COV-2 by a molecular docking approach. The main bioactive compounds present in the plant extracts were identified by HPLC-MS. According to the results, the extracts of yerba mate and jarilla showed high antioxidant activity in DPPH (> 91 %), ABTS (> 90 %), and FRAP (> 47 mg TE/g) assays. Additionally, the phenolic compounds present in yerba mate, quercetin-3-O-rutinoside (rutin) (-9.60 kcal/mol) and 3,4-dicaffeoylquinic acid (-8.20 kcal/mol) were more effective on Mpro than the antiviral drugs remdesivir and ribavirin. The compounds rutin and 3,4-dicaffeoylquinic acid have a high affinity and interaction with one of the catalytic residues Cys145 of Mpro. The glycosylation of phenolic compounds affects biological activities: positively anti-COVID-19 and negatively antioxidant. The results suggest that extracts of yerba mate and jarilla leaves could enhance the body's antioxidant defenses and can be used to improve health.

Exploration of Phenolic Content and Antioxidant Potential from Plants Used in Traditional Medicine in Viesca, Mexico

“…The samples were incubated for 5 min at room temperature, and the absorbance at 760 nm was measured in a spectrophotometer (Velab, Pharr, TX, USA). The concentration of phenolic compounds was calculated according to the calibration curve of gallic acid in Equation (1).…”

“…Medicinal plants and their phytochemicals have been used for the treatment of various diseases for a long time [1]. The identification of new plants with medicinal properties is of great importance, as approximately 60% of the new medicines produced since 1981 came from plants [2].…”