Evolución del potencial antibacteriano y sinérgico de antraquinonas sintéticas sobre bacterias Gram-negativas resistentes a ciprofloxacina.

Abstract

Antibiotics are used to treat bacterial diseases, but the emergence of resistant strains has become a global health problem. Anthraquinones are natural molecules with therapeutic effects. However, synthetic derivatives have been little studied. Objective: To evaluate the antibacterial effects of synthetic chlorinated, hydroxylated, and nitrated anthraquinones alone and combined with ciprofloxacin. Methods: The evaluation was performed on ciprofloxacin-resistant bacterial strains such as Escherichia coli and Klebsiella pneumoniae. Sensitivity to anthraquinones was evaluated by the Kirby-Bauer method using paper platelets. The macrodilution method in agar was used to determine MICs. Finally, bacteria were exposed to anthraquinones, and their effect was compared with the antibiotic without combination. Results: Information was provided on synthetic anthraquinones' antibacterial and synergistic capacity on ciprofloxacin-resistant bacteria, showing that anthraquinones had no antibacterial or synergistic effect on ciprofloxacin-resistant Klebsiella pneumoniae and Escherichia coli. However, 1,8-dihydroxy-4,5-dinitroanthraquinone showed the ability to increase the effect of ampicillin on Escherichia coli. Conclusion: This group of synthetic anthraquinones has expanded knowledge of the antibacterial potential. The hydroxyl, nitro, and chloride functional groups were also highlighted, indicating that none of the functional groups of anthraquinones have direct antibacterial activity. However, the combination of hydroxyl and nitro groups present in 1,8-dihydroxy-4,5-dinitroanthraquinone can increase the effect of ampicillin on Escherichia coli.