Polyene antimycotics, sometimes referred to as polyene antibiotics, are a class of antimicrobialpolyenecompounds that target fungi.[1] These polyene antimycotics are typically obtained from certain species of Streptomyces bacteria. Previously, polyenes were thought to bind to ergosterol in the fungal cell membrane, weakening it and causing leakage of K+ and Na+ ions, which could contribute to fungal cell death. However, more detailed studies of polyene molecular properties have challenged this model suggesting that polyenes instead bind and extract ergosterol directly from the cellular membrane thus disrupting the many cellular functions ergosterols perform.[2][3]Amphotericin B, nystatin, and natamycin are examples of polyene antimycotics. They are a subgroup of macrolides.[4]