Chemical profiling and assessment of neurobiological properties of Veronica teucrium and Veronica jacquinii methanolic extracts

Veronica genus (Plantaginaceae) comprises around 450 species, which have been used in folk medicine of Europe and Asia for the treatment of certain problems with nervous, and respiratory system, wound healing, as well as a diuretic [1]. On the other hand, there is lack of scientific evidence to support the traditional use of Veronica species. In this study, the neuroprotective potential of V. teucrium L. and V. jaquinii bachofenii Heuff. was investigated while HPLC-DAD/ESI-MS technique was used for qualitative and quantitative analyses of phenolic compounds. Chemical analysis showed the presence of phenolic acids and flavonoids in both species and also secoiridoids in V. teucrium. The detected flavonoids derived from flavones (luteolin and isoscutellarein in V. jacquinii; apigenin, isoscutellarein and luteolin in V. teucrium) and a flavonol (quercetin in V. jacquinii). Acteoside was the dominant compound in V. jacquinii methanolic extract, while in V. teucrium major phenolics were plantamajoside and isoscutellarein 7-O-(6'''-O-acetyl)-β-allosyl (1'''→2''')-β-glucoside. Antineurodegenerative activity was tested at concentrations of 25, 50 and 100 µg/mL using acetylcholinesterase (AChE) and tyrosinase (TYR) assays. Inhibition of both enzymes was obtained by both extracts and it ranged from 22.78 to 35.40% for AChE and from 9.57 to 16.38% for TYR. There were no statistical differences between the activities of extracts, but they showed statistically weaker activity than the standards galanthamine for AChE assay and kojic acid for TYR assay. Our data indicate that V. teucrium and V. jaquinii may have beneficial effects against diseases such as Alzheimer's and Parkinson's disease.