Avaliação da Atividade Antibacteriana, Antioxidante e Toxicológica do Flavonoide isolado de Lonchocarpus araripensis (Leguminosae): Estudos in silico e in vitro

Abstract

Bacterial infections, which affect millions of people around the world, have progressively increased in recent years, impacting the rate of morbidity and mortality. The spread of drug-resistant bacteria is one of the most serious threats to successful treatment of bacterial diseases, in addition, some drugs are very toxic, making it difficult to adhere to treatment. In this context, flavonoids have been distinguished by their diverse pharmacological activities, such as: bactericide, fungicide and antioxidant. Based on this, the antibacterial and antioxidant effects, the theoretical oral bioavailability and the toxicological profile of the flavonoid 2,4-cis-3,4-cis-3,4,5,8- tetramethoxy- [1 '', 2 '': 6,7] –furanoflavane (TMFF), isolated from the hexane extract of the bark of the roots of Lonchocarpus araripensis. To analyze the antimicrobial potential of flavonoid, in silico analysis with the Pass online software was used. For the accomplishment of the antibacterial studies the microdilution test with different strains of the bacteria Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa was used to evaluate the Minimum Inhibitory Concentration (MIC). In addition, the Minimum Bactericidal Concentration (MBC) was also determined. In the study of association of flavonoid with clinically used antibiotics, the ability of flavonoid to promote synergism, indifference or antagonism after association. In the accomplishment of the studies of antioxidant activity in vitro was used the technique of the chelating effect on the ferrous ion. For the in silico toxicological analysis the tool was used admetSAR and for the evaluation of oral bioavailability theoretically in silico was used the program Molinspiration Cheminformatics. The in silico study demonstrated that flavonoid presented a high probability of being active against several microorganisms, including bacteria. The experiments of antibacterial activity revealed that the flavonoid had a bacterial effect against gram positive and gram negative species, with MIC50 of 64 μg/mL for some strains of Pseudomonas aeruginosa, on different strains of Staphylococcus aureus, the flavonoid presented MIC50 of 256 μg/ml and on one of the tested strains of Escherichia coli the MIC50 was 512 μg/ml. Flavonoid has been shown to be bacteriostatic for all bacterial species tested and also showed a synergistic effect. In the antioxidant activity studies, flavonoid presented a chelating effect on the ferrous ion. Flavonoid demonstrated low theoretical toxicity as well as good oral bioavailability through in silico analysis. These results suggest that flavonoid has an antibacterial and antioxidant effect, with a low toxicological effect.