Amphotericin B is a polyene antifungal isolated fromStreptomycesspecies. While it has been suggested that Amphotericin B interacts with ergosterol of the fungal cell membrane leading to an altered cell membrane permeability and death, more recent studies show that the mechanism behind amphotericin B’s fungicidal activity is more complex. It is most effective against fungi and yeast and is often used against opportunistic fungal infections and leishmaniasis. Additionally, amphotericin B can be used to prevent growth ofF. oxysporumin chickpea andP. triticinain wheat.
Amphotericin B is often used in clinical in vitro tests known as antimicrobial susceptibility tests or ASTs to determine their efficacy against certain bacterial species. They are tested against gram-negative and gram-positive bacteria using panels, discs, and MIC strips by medical microbiologists. ASTs decrease the risk of using an antibiotic against bacteria exhibiting resistance to it, and the results are used in clinical settings to determine which antibiotic(s) to prescribe for various infections.