Determinação da localização geográfica do Gervão roxo (Stachytarpheta sellowiana Schauer) e potencial farmacológico do seu extrato bruto etanólico

Abstract

Stachytarpheta sellowiana Schauer, popularly known as purple gervão, is a shrub endemic to Brazil, described for the first time in 1851 as an extremely rare species, belonging to then Verbenaceae family, found only in Minas Gerais. Only 35 records of it are documented, highlighting the lack of studies on Brazilian flora. The genus Stachytarpheta has around 82 species known for their pharmacological potential, being described with anti-inflammatory, antimalarial, anti-leishmanial, antibiotic, hypoglycemic and other properties. It is assumed that this poorly documented species has similar medicinal properties. The aim is to evaluate the pharmacological potential of this plant, starting with its toxicity through the zebrafish (Danio rerio) biological model, elucidate its place of occurrence, as well as begin phytochemical research on the extract and evaluate its leishmanicidal activity. The extract was prepared by the dynamic maceration method with EtOH 92.80o INPM, rotary evaporated and freeze-dried. Different dilutions were prepared for application to zebrafish embryos to define the average lethal concentration (LC50), the safe doses were tested on the protozoan Leishmania amazonensis, looking for the LC50 in this species, and the crude ethanolic extract was quantified for the levels of phenolic compounds and total flavonoids by ultraviolet molecular absorption spectrophotometry. The design used was completely randomized, with 25 embryos pertreatment and seven treatments (0.0; 100.0; 250.0; 500.0; 750.0, 1,000.0 and 2,000.0 μg/ml),with three repetitions. After exposure, the specimens were evaluated and with the values obtained, through statistical analyses, the LC50 in the zebrafish biological model was established at 250.0 μg/ml<, the extract did not show leishmanicidal activity with the L. amazonensis strain, the phenol and flavonoid contents were 9.61 ± 0.31 mg Eq. Q/g and 15.03 ± 0.28 mg Eq. AG/g, respectively. Among the occurrence characteristics attributed to the plant, the altitudinal restriction was the only one confirmed by the study. The results obtained shed light on the complex interaction between a medicinal plant and the development of a phytopharmaceutical, providing crucial information for future therapeutic developments.