Investigação da atividade antifúngica do ácido 2-furanilborônico contra fungos do gênero Candida e outras leveduras.

Abstract

The genus Candida comprises a group of species that reside as commensals in the human body, colonizing the skin, oral mucosa, gastrointestinal tract and genitourinary tract. However, when there is an imbalance in the microbiota or immune system, these microorganisms can become pathogenic, causing superficial or more severe infections. The main species of clinical interest are: Candida albicans, Candida tropicalis, Nakaseomyces glabrata (Candida glabrata), Pichia kudriavzevii (Candida krusei), Candida guilliermondii, Candida parapsilosis, Candida auris. Additionally, fungal infections resistant to existing therapy have increased significantly due to the indiscriminate use of antifungals for prophylaxis and therapy. In organic chemistry, boronic acid is a compound widely studied due to its various activities, including: anticancer, antibacterial, antifungal and antiviral, with even medications already being marketed with this class of organic function. The potential of 2-furanylboronic acid, derived from boronic acid, is still unknown and there are no studies on its biological activity. The objective of the study was to determine the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of 2-furanylboronic acid against strains of Candida spp and other yeasts. The MIC was based on the serial microdilution technique, using 100 μL of doubly concentrated culture medium (sabouraud dextrose agar) and 100 μL of the test substance, in concentrations ranging from 1024 μg/mL to 0.5 μg/mL. Then, 10 μL of the inoculum adjusted to a 0.5 McFarland scale were added. Based on the results obtained from the MIC, the CFM was performed, removing an aliquot of 10 μL from the cavities that did not visibly show fungal growth (in concentrations equal to or greater than the MIC), and then placed in Petri dishes containing sabouraud agar dextrose. The MIC results for 2-furanylboronic acid were equivalent to 1024 μg/mL for the strains of Candida albicans ATCC-60193, Candida albicans ATCC-10231, Pichia kudriavzevii (Candida krusei) ATCC-6258 and Candida tropicalis ATCC-13803. However, under the conditions evaluated, 2- furanylboronic acid did not present CFM against any of the strains used in the test. Finally, this work addressed the activity of 2-furanylboronic acid against strains of Candida spp and other yeasts and thus, under the conditions evaluated, 2- furanylboronic acid showed activity only against four of the eight strains used in the test. However, knowing the potential of this class of organic function, it is worthwhile to carry out more studies and tests to evaluate the activity of 2-furanylboronic acid against other microorganisms, taking into account the potential of boronic acid in different areas and scientific and medical applicability.