Avaliação de extratos aquosos de três espécies de Kalanchoe: impacto em modelo animal de ansiedade, perfil químico e análise farmacobotânica

Abstract

Kalanchoe species, known as "miracle leaves" in traditional medicine, pose differentiation challenges due to their morphological similarities, increasing the risk of improper use. The study investigated the botanical diversity and biochemical properties of three Kalanchoe species, widely used in traditional medicine for their alleged therapeutic properties, especially in treating anxiety. The species studied, Kalanchoe crenata, Kalanchoe marmorata, and Kalanchoe pinnata, were collected and processed using ethnopharmacological methods for the extraction of bioactive compounds. The study employed a combination of analytical techniques, including botanical analysis, determination of phenolic and flavonoid content, antioxidant activity assays (DPPH•

, ABTS•+, ORAC), and advanced chromatographic methods (HPLC- PDA, HPLC-MS, and HPTLC). These approaches allowed for a detailed evaluation of

the chemical composition of the species and a comparison of their antioxidant capacities. The results indicated significant differences among the species. Botanical analyses revealed that only K. pinnata has calcium oxalate crystals in the petiole, a distinctive marker of this species. In terms of antioxidant capacity, K. marmorata showed the highest values in all assays, suggesting a higher concentration of bioactive compounds. Chromatographic analysis confirmed the presence of flavonoids, mainly quercetin derivatives, with K. pinnata displaying a unique chemical profile of quercetin arabinosil rhamnoside. Additionally, the research explored the anxiolytic activity through in vivo evaluation, suggesting that K. pinnata may offer benefits in anxiety treatment. This discovery underscores the importance of accurately differentiating Kalanchoe species for appropriate and safe medicinal use. This study provides valuable insights into the botanical and pharmacological characteristics of Kalanchoe, which can guide the traditional use of these plants as well as inspire future scientific investigations and therapeutic applications.