ANTIMICROBIAL ACTIVITY AND SYNERGIC EFFECTS OF THE SYNTHETIC CUMARIN DERIVATIVE 4-hydroxycoumarin IN ISOLATES OF THE SPECIES Candida albicans
Candida albicans, coumarins, 4 – hydroxycoumarin, antifungal activity, synergism.
Fungal infections have become a major challenge in view of the impact of resistance to usual antifungal agents on therapeutic management, in addition to the lack of implementation of more advanced diagnostic techniques in public health units. Concomitantly, a greater number of cases is observed, reflecting an increase in the incidence of fungal diseases, both in immunosuppression conditions and in exogenously acquired infectious processes. Species of the genus Candida continue to be the most implicated in invasive fungal infections, which notoriously trigger high mortality rates. Species of the genus Candida continue to be the most implicated in invasive fungal infections, which notoriously trigger high mortality rates. Given this scenario, there was an increase in the development and commercialization of new antifungal agents, as well as the implementation of strategies to prevent candidemia. Studies with bioactive products derived from plants, which historically have well-described biological properties and which demonstrate safety in terms of toxicity, have been evaluated for a more effective application. One of the compounds under study are coumarins and their derivatives, such as 4-hydroxycoumarin, which has important attributes, including antiviral, antitumor and anticoagulant properties. In this context, the objective of this work was to evaluate the antifungal activity of the synthetic phenolic compound 4-hydroxycoumarin on Candida albicans samples, as well as to analyze the synergistic effects between this phenolic compound and the antifungal Amphotericin B. The biological activity of 4-hydroxycoumarin was investigated in 17 samples of Candida albicans, in which the Minimum Inhibitory Concentration (MIC) was evaluated by the broth microdilution technique and by the Minimum Fungicide Concentration (MFC) method. To carry out the synergistic activity, 5 samples of the species C. albicans were selected considering criteria of pathogenicity among the 17 strains, as well as the results of the MIC, being performed using the Checkerboard method. Among the 17 strains tested, antifungal activity was found for 15 strains, with MIC ranging from 5.0 to 0.625 mg/mL, and the CFM determined ranging from 5.0 to 1.25 mg/mL. Regarding the evaluation of the synergistic effect between the synthetic compound and the antifungal, it was seen that this combination presented an additive and indifferent character against some strains among yeasts of the C. albicans species tested. It was concluded that 4-Hydroxycoumarin showed antifungal activity, mostly of a fugitive nature, in order to reduce the yeast load, but it was not efficient when associated with Amphotericin B, an antifungal with a fungicidal character. The results suggest that this compound may be a promising strategy in antifungal therapy.