Revista Cubana de Plantas Medicinales
versão ISSN 1028-4796
MARTINEZ, Maby M; OCAMPO, Diana M; GALVIS, Jhon H e VALENCIA, Andrea. Antibacterial activity and in vivo cytotoxicity of ethanol extracts from Bauhinia variegata L. (Fabaceae). Rev Cubana Plant Med [online]. 2011, vol.16, n.4, pp. 313-323. ISSN 1028-4796.
Introduction: several research studies have identified the biological potential of different compounds such as flavonoids, tannins, steroids, naphtoquinones and sesquiterpenoid present in the genus Bauhinia. It has been reported for the species B. variegata the presence of flavonoids with anti-diabetic and antiviral properties, but the study of antibiotic and cytotoxic potential is just incipient for both flavonoid and alkaloid compounds. Objective: to determine the antibacterial and in vivo cytotoxic activity of alkaloid extracts from Bauhinia variegata L. Methods: column chromatography for extraction and isolation of alkaloids in B. variegata.leaves was performed. Alkaloid extracts and fractions were tested through bioassay for their cytotoxic potential on "brine shrimp" (Artemia salina) and the antibacterial potential on Escherichia coli through the disk diffusion method (antibiogram by diffusion). Results: six compounds were purified and measured the presence of the protoberberinic nucleus by means of UV spectrophotometry. Regarding Artemia salina bioassay, the crude extract (CE) showed less toxicity (LC50> 1000 µg/mL), whereas the fraction of the total alkaloid fraction (TA) and the CD1 compound showed high toxicity (LC50< 500 µg/mL). Unlike the evidence for the antimicrobial bioassay, no inhibition zones for treatment with the extracts and the compounds appeared. Conclusions: the reported cytotoxic activity is caused by the synergistic effect of all secondary metabolites that could occur in the plant, which were also associated with this activity (alkaloids and terpenes) that account for the toxicity shown by the total alkaloid fraction.
Palavras-chave : alkaloids; Artemia salina; Bauhinia; cytotoxicity; Escherichia coli.