Figure 3

Identification of amphotericin B. The preparative and analytical results of the experiments identifying the only substance with antimicrobial activity in a culture extract of Penicillium nalgiovense Laxa. The methanol extracts of the mycelial growth and liquid filtrate were fractionated with HPLC (bottom two chromatograms recorded at 280 nm), analyzed with Q-TOF MS (middle spectra), and compared with the reference substance amphotericin B (top figure). Identical elution times (21 minutes 50 seconds), mother ions (924.4989 and 906.4837 m/z), and daughter ions (743.5, 761.5 m/z) between the extracted compound and reference amphotericin B, together with NMR analysis and antimicrobial assays, led to the identification of amphotericin B in the fungal extracts.