Variability and Chemical Composition of Aerials Parts of Verbena minutiflora

Abstract

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 APPLICATIONSMedicinal 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.

Bioaccessibility of Metallic Ions and Phenolic Compounds in Teas From Miconia Albicans

“…In the literature, it is described that plants tend to have higher concentrations of metals and organic compounds in their aerial parts, such as leaves (SOARES, et al, 2015). The CV samples, in addition to the leaves, also contained parts of the stem.…”

“…To quantify the total levels of phenolic compounds, the Folin-Ciocalteau colorimetric method was used using an analytical curve (40.0 to 340 mg L -1 ) of gallic acid in methanol (SCHMIDT, et al, 2014;SOARES, et al, 2015).…”

“…The quantification of flavonoid contents was performed by complexation with aluminum chloride at 5% m v -1 in methanol (SCHMIDT, et al, 2014;SOARES, et al, 2015). The analytical curve of quercetin (10.0 to 125.0 mg L -1 ) was performed in methanol.…”

<b>Multi-element analysis in aerials parts of <i>Verbena minutiflora</i> and infusions

“…The Verbenaceae is popularly known as Gervão, Gervão-roxo, Rinchão, Gervão do campo, and Vassourinha de botão; and is frequently used as infusion (tea) in the treatment of various diseases (Schapoval et al, 1998). However, at present few studies have been found on chemical and pharmacological validation of this plant (Soares et al, 2016;Peloi, Bovo, Messias-Reason, & Perez, 2016).…”