Catechin potentiates the antifungal effect of miconazole in Candida glabrata

Abstract

The rising number of invasive fungal infections caused by drug-resistant Candida strains is one of the greatest challenges for the development of novel antifungal strategies. The scarcity of available antifungals has drawn attention to the potential of natural products as antifungals and in combinational therapies. One of these is catechins—polyphenolic compounds—flavanols, found in a variety of plants. In this work, we evaluated the changes in the susceptibility of Candida glabrata strain characterized at the laboratory level and clinical isolates using the combination of catechin and antifungal azoles. Catechin alone had no antifungal activity within the concentration range tested. Its use in combination with miconazole resulted in complete inhibition of growth in the sensitive C. glabrata isolate and a significant growth reduction in the azole resistant C. glabrata clinical isolate. Simultaneous use of catechin and miconazole leads to increased intracellular ROS generation. The enhanced susceptibility of C. glabrata clinical isolates to miconazole by catechin was accompanied with the intracellular accumulation of ROS and changes in the plasma membrane permeability, as measured using fluorescence anisotropy, affecting the function of plasma membrane proteins.

Antifungal Activity and Type of Interaction of Melissa officinalis Essential Oil with Antimycotics against Biofilms of Multidrug-Resistant Candida Isolates from Vulvovaginal Mucosa

“…Also, it must be emphasized that in the analysis reported here, we calculated all the combinations of concentrations, allowing for a much deeper understanding of the interactions that take place. Up to now, synergism against candidal biofilms has been tested for certain natural compounds, such as pseudolaric acid A [72]; catechins [73]; paeonol [68]; allyl isothiocyanate [74]; thymol and eugenol [75]; carvacrol, thymol, and eugenol [76]; allicin [77]; and other natural compounds of plant origin such as quercetin [29] or shikonin [78]. Up to now, the only study that investigated the combined effect of essential oils and antifungal drugs on candidal strains was performed by Jafri and Ahmad, where synergism was found between Thymus vulgaris and thymol against drug-resistant strains of C. albicans and C. tropicalis [79].…”

Plant‐derived virulence arresting drugs as novel antimicrobial agents: Discovery, perspective, and challenges in clinical use

“…Catechin is a typical 2,3-trans type polyphenolic compound with potential antibacterial and antivirulence effects (Hervay et al, 2023).…”