Variability and Chemical Composition of Aerials Parts of Verbena minutiflora

Verbena minutiflora (Verbenaceae) is popularly consumed as an infusion for the treatment of various diseases. However, so far there is no pharmacological or chemical validation to support its therapeutic applications. Therefore, the analysis of the chemical composition and pharmacological activities of V. minutiflora is crucial. In this study, extracts and infusions of the aerial parts of V. minutiflora (leaves, flowers and stems) were analyzed during four consecutive years. Extracts of leaves and flowers had significantly higher phenolic content and antiradical capacity than stems regardless of the year of collection. The infusions of leaves presented constant composition throughout the studied period with high levels of bioactive compounds and high antioxidant potential. Samples were analyzed by HPLC with photodiode array detector (HPLC‐DAD) and by LC‐ESI‐MS/MS, and the potent antioxidants verbascoside and isoverbascoside (phenylpropanoids) and the iridoid hastatoside were tentatively identified in extracts and infusions of the aerial parts of V. minutiflora. Practical Applications Medicinal plants are used since ancient times and are increasingly attracting worldwide attention as functional foods or beverages. Verbena minutiflora is popularly consumed as an infusion to reduce the levels of glucose and cholesterol in blood. Despite its popularity, so far there is no pharmaceutical or chemical validation to support their therapeutic applications. Therefore, it is extremely important to identify the main bioactive constituents of V. minutiflora in order for the plant to be safely used as a phytotherapeutic resource. All extracts showed high concentration of phenolic compounds and therefore potential antiradical capacity, especially the extracts of leaves and flowers. Despite lower amounts of phenolic and flavonoid compounds extracted by hot water, infusions showed high antiradical capacity that might be due to the presence of hastatoside, verbascoside and its isomers. This result justifies the popular intake of infusions of V. minutiflora as a source of antioxidant compounds.