Caspofungin cas

The susceptibility of a C. auris biofilm grown in the presence of Van PP to the antifungal caspofungin (CAS) (Sigma-Aldrich Co, St. Louis, MO, USA) was evaluated. Aiming at this, the C. auris biofilms were grown for 72 h, as previously described with or without Van at PP concentration, washed with NaCl 0.9%, and treated with CAS (ranging from 2.5 to 50 µg mL⁻¹). After 24 h further incubation, total biofilm biomass was quantified.

We calculated the minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) of the twelve clinical strains of C. parapsilosis using Fluconazole (FLZ; Sigma-Aldrich, St. Louis, MO, USA), Amphotericin B (AmB; Sigma-Aldrich, USA), Nystatin (NYST; Sigma-Aldrich, USA), and Caspofungin (CAS; Sigma-Aldrich, USA). A broth microdilution assay was performed under the guidelines recommended in the standard M27 document (4th ed.) presented by the Clinical and Laboratory Standard Institute [14 ]. The stock solution of the prior mentioned drugs was prepared using dimethyl sulfoxide (DMSO; Merck, RSA) and the test concentration ranged from 1250 to 9.77 µg/mL for FLZ, 62.5 to 0.49 µg/mL for AmB, 250 to 19.5 µg/mL for NYST, and 8 to 0.06 µg/mL for CAS. Sterility and growth control were included for comparison. The plates were incubated at 37 °C for 48 h. The MIC results were determined by visual observation, where antifungal drugs with the lowest concentration inhibited the fungal growth when compared to the growth control was considered as MIC value.
For estimating MFC, 10 µL from the wells with different concentrations of antifungal drugs were subcultured onto Sabouraud dextrose agar (SDA; Merck, RSA) plates followed by incubation at 37 °C for 48 h. The MFC was determined by observing the lowest concentration with no growth on the agar plate [15 (link)].

To analyze the impact of thermal treatment on conidiation, wild-type and relevant strains were cultured at 30, 37 and 42 °C. To obtain the impact of cell wall stress, we tested the condition of fungal growth on a medium supplemented with the following agents: calcofluor white (CFW), congo red (CR), and caspofungin (CAS) (Sigma-Aldrich, St. Louis, MO, USA). In order to test the restorative effect of calcium on fungal growth, 50 mM of CaCl₂ was added to the medium. The operation process was as follows: 2.5 μL of the conidia (1 × 10⁶ conidia·mL⁻¹) of the indicated strains were spotted onto relevant media and cultured for 2.5 days. Finally, the colony diameter was measured, and the total spore quantity of all strains was counted. At least three replicates were performed for each experiment.