The influence of environmental variations on the phenolic compound profiles and antioxidant activity of two medicinal Patagonian valerians (Valeriana carnosa Sm. and V. clarionifolia Phil.)

NAGAHAMA NICOLÁS; GASTALDI, B; CLIFFORD, MICHAEL; MARIA M. MANIFESTO; RENÉE H. FORTUNATO

AIMS Agriculture and Food

AIMS Press

Lugar: Springfield; Año: 2020 vol. 6 p. 106 - 124

Valeriana carnosaand V. clarionifolia stand out asprincipal elements in the indigenous pharmacopeias of Patagonia; however, theirphytochemical characterization is unknown. This study constitutesthe starting point of a general project that aims to characterize secondarymetabolites in these species. The variability of phenolic compounds inroot ethanolic extracts was analyzed and compared for thirteen populations of V.carnosa and two of V. clarionifoliafrom the south of Argentinean Patagonia. Phenolic content wasquantified by the Folin-Ciocalteu method and the putative phenolic compoundprofiles were investigated using HPLC-UV-MS. Antioxidant activity was evaluatedthrough 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. Totalphenolic content values ranged from 5.6 to 16.6 mg GAE/g in V. carnosa and 7.3 to 9.7 mg GAE/g in V. clarionifolia. Antioxidant evaluationresults evidenced that the percentage of neutralized DPPH varied between 26%and 85% in V. carnosa and 39% and 58%in V. clarionifolia. A positivecorrelation between total phenolic content and antioxidant activity (r = 0.90) was observed. InV. carnosa total phenolic content wasnot correlated with altitude or latitude (p > 0.05), and chemical variability seems to be associated withgenetic variability and/or different growing habitats (microclimatic conditions). However, the presence of some specificphenolic compounds was associated with latitude. In V. carnosa and V.clarionifolia 15 and 10 phenolic compounds were tentatively identified,respectively, and several of these are reported to have beneficial attributes from a phytomedical viewpoint.This study contributes to the phytochemical characterization project of thesetwo medicinal valerians from Patagonia.