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Exploring drug susceptibility is a critical endeavor in the scientific community, setting the stage for advancements in understanding and combating various pathogens. Candida kefyr has emerged as a significant pathogen, particularly affecting immunocompromised individuals with hematologic malignancies and HIV/AIDS conditions. This study aimed to assess the antifungal susceptibility profile of Candida kefyr isolates obtained from clinical samples and dairy products. A total of 134 Candida kefyr yeast isolates were retrieved from three distinct groups: (1) healthy individuals (n = 41), (2) patients (n = 24) including hematologic malignancy (n = 9), HIV/AIDS (n = 7), and diabetes (n = 8), (3) dairy products (milk, yogurt, and cheese, n = 69) stored at −70°C in the Shiraz University of Medical Science. All Candida kefyr isolates were previously identified using conventional and molecular methods. Susceptibility to antifungal drugs, including caspofungin, fluconazole, itraconazole, voriconazole, and amphotericin B, was determined using the microdilution method following CLSI‐M27‐A3 protocols, with results interpreted according to CLSI‐M27‐S4 guidelines. The study emphasizes the clear variation in antifungal susceptibility testing of Candida kefyr strains when compared across different groups, including patients, healthy people, and dairy products. According to the results, across all groups, a high minimum inhibitory concentration of fluconazole is evident, and healthy individuals show the highest minimum inhibitory concentration geometric means (4.0681). Also, 79.1% of the isolates were wild type to amphotericin B, with the lowest minimum inhibitory concentration compared to other antifungals tested. This suggests that amphotericin B was more effective against Candida kefyr. These findings showed fewer susceptibilities of Candida kefyr to both triazole and echinocandin classes of antifungal agents. Additionally, it is noteworthy that individuals without medical conditions exhibited higher minimum inhibitory concentration rates to these antifungal agents in comparison to those with underlying health conditions. Consequently, timely diagnosis and appropriate therapeutic interventions emerge as imperative in the effective management of candidiasis cases. [ABSTRACT FROM AUTHOR]

Super-paramagnetic iron oxide nanoparticles were synthesized by a co-precipitation method, which was further functionalized with chitosan (CS). The composite was investigated for binding with Nystatin (Nyst), a polyene polyhydroxy antifungal widely used in management of mucocutaneous fungal infections. The structure of the Fe3O4/CS/Nyst composite was characterized by different physicochemical techniques. Transmission electron microscope analysis revealed the Fe3O4/CS/Nyst composite with a mean diameter of ∼10–20 nm in a monodispersed spherical form. Fourier-transform infrared spectroscopy analysis confirmed the binding of CS on Fe3O4 NPs and also the loading of Nyst on the nanostructure. The UV–Vis absorption spectroscopy demonstrated the Nyst drug loading by 22% capacity. The antifungal activity of the Fe3O4/CS/Nyst was evaluated against Candida species and Aspergillus fumigatus, which demonstrated excellent activity with a minimum inhibitory concentration ranging from 2 to 16 μg/mL. The MTT assay was used to evaluate the toxicity of compounds which did not reveal any toxic effect on the adipose derived mesenchymal stem cells. Regarding remarkable antifungal activities and low toxicity of this magnetic nano-compound, it could be a good candidate for target therapy of mucocutaneous and local fungal infections. [ABSTRACT FROM AUTHOR]

The global landscape of Candida infections has seen a significant shift. Previously, Candida albicans was the predominant species. However, there has been an emergence of non‐albicans Candida species, which are often less susceptible to antifungal treatment. Candida kefyr, in particular, has been increasingly associated with infections. This study aimed to investigate the profiles of enzymatic activity and biofilm formation in both clinical and non‐clinical isolates of C. kefyr. A total of 66 C. kefyr isolates were analysed. The activities of proteinase and phospholipase were assessed using bovine serum albumin and egg yolk agar, respectively. Haemolysin, caseinolytic and esterase activities were evaluated using specific methods. Biofilm formation was investigated using crystal violet staining. The findings indicated that biofilm and proteinase activity were detected in 81.8% and 93.9% of all the isolates, respectively. Haemolysin activity was observed with the highest occurrence (95.5%) among normal microbiota isolates. Esterase activity was predominantly identified in dairy samples and was absent in hospital samples. Caseinase production was found with the highest occurrence (18.2%) in normal microbiota and hospital samples. Phospholipase activity was limited, found in only 3% of all the isolates. These findings reveal variations in enzyme activity between clinical and non‐clinical C. kefyr isolates. This sheds light on their pathogenic potential and has implications for therapeutic strategies. [ABSTRACT FROM AUTHOR]

Candida onychomycosis is a common fungal infection affecting the nails, primarily caused by Candida (C.) species. Regarding the increasing trend of Candida onychomycosis and the antifungal resistant phenomenon in recent years, this study aims to evaluate the epidemiological characteristics of Candida onychomycosis, the distribution of emerging species, and the antifungal susceptibility profiles of isolates. Onychomycosis caused by yeast species was confirmed through direct examination and culture of nail scraping among all individuals suspected to have onychomycosis and referred to a medical mycology laboratory between June 2019 and March 2022. Species of yeast isolates were identified using the multiplex PCR and PCR-RFLP methods. The antifungal susceptibility of isolates to common antifungal agents and imidazole drugs was evaluated according to the M-27-A3 CLSI protocol. Among 101 yeast strains isolated from onychomycosis, Candida parapsilosis complex (50.49%) was the most common species, followed by C. albicans (20.79%) and C. tropicalis (10.89%). Rare species of yeasts such as C. guilliermondii and Saccharomyces cerevisiae were also identified by molecular methods. Results obtained from antifungal susceptibility testing showed significant differences in MIC values of isoconazole, fenticonazole, and sertaconazole among different species. Overall, a fluconazole-resistant rate of 3% was found among Candida species. Moreover, there was a statistically significant difference in MICs of fenticonazole and clotrimazole between the two most prevalent causative species, C. parapsilosis complex and C. albicans. Correct identification of the causative agents of onychomycosis and performing susceptibility testing could be helpful in choosing the most appropriate antifungal therapy. [ABSTRACT FROM AUTHOR]

Despite extensive research on antimicrobial drugs, efforts to find suitable alternatives to older drugs have not been very successful yet, due to microbial resistance. Heterocycles including azole and pyrimidine derivatives were used to design antimicrobial activity in this research, 12 novel pyrimidine-azole derivatives (3a-3l) that were previously synthesized were screened for their antibacterial and antifungal activities by using CLSI standard method. In this study, we used four species of bacteria, seven species of fungi, and five species of yeast. Molecular docking studies were also performed to investigate their binding mode and orientation toward lanosterol 14-α-demethylase (CYP51), as a plausible mechanism of azole antifungal compounds. The biological results showed that none of the compounds had antibacterial and antifungal effects compared to the control drugs. The molecular docking study showed that the compounds had a low binding affinity in the active site of the lanosterol 14-α-demethylase target, which confirmed the weak antifungal and antibacterial activities of these compounds. [ABSTRACT FROM AUTHOR]