A Comparative Analysis of the Polyphenolic Content and Identification of New Compounds from Oenothera biennis L. Species from the Wild Flora

<i>Oenothera biennis</i> L. is a biennial species native to North America and introduced to Europe in the 17th-18th centuries, used in traditional medicine or as a dietary supplement in various products, as well as in cosmetics and the pharmaceutical industry. In recent decades, oil extracted from seeds has been increasingly used for the treatment of various conditions. In this article, we highlight the polyphenolic content of 2 types of extracts from <i>O. biennis</i> species, collected from the wild flora of Romania, from two regions with different altitudes and pedoclimatic conditions (plains and mountains), namely: OHM-hydroalcoholic extract, Macea sample; OHVD-hydroalcoholic extract, Vatra Dornei; OAM-aqueous extract, Macea sample; OAVD-aqueous extract, Vatra Dornei sample. The LC/MS analysis of the whole plant extracts revealed 5 to 14 polyphenols, depending on the sample location and type of extract, out of which 7 flavonoids are newly reported for this species. Climatic parameters were mapped using QGIS. Higher qualitative and quantitative values of polyphenols were observed in the hydroalcoholic extract obtained from individuals collected from the plain area.