Estudo químico e biológico do extrato aquoso de Hibiscus sabdariffa

Abstract

Hibiscus sabdariffa, popularly known as hibiscus, vinegar or guinea okra, is a plant that has gained great interest in academic research. Most likely due to its antioxidant property. Although there are several studies reporting the use of Hibiscus sabdariffa, to date, its antioxidant action in strains of wild Escherichia coli (AB 1157) has not been described in the presence and absence of the reducing agent stannous chloride, as well as and bioassays of toxicity on Artemia salina Leach. The preliminary phytochemical profile of the aqueous extract of the Hibiscus sabdariffa chalices showed flavonoids, anthocyanins, coumarins and saponins. The antioxidant potential was 324.95 mM Trolox / g measured by ABTS. The median lethal dose (LD50) of the extract was 1000 ppm, proving to be toxic at this concentration. The extract showed antimicrobial action at a dose of 24 µL and synergism when associated with chloramphenicol discs in strains of wild Escherichia coli (AB 1157). Anthocyanins were identified through CLUE-ESI-TOF-EM: cyanidin 3-sambubioside and delfinidine 3- sambubioside as the major constituent of the extract.