Abstract: Based on the taxonomic study, the antifungal antibiotic S1 producer FIM95-F1 was named as Streptomyces castelarensis FIM 95-F1 tentatively. The bioactive metabolite S1 was isolated and purified from the mycelia of strain FIM 95-F1 using high speed countercurrent chromatography (HSCCC) and crystallization methods. Basic physico-chemical properties and UV, IR, MS, and NMR spectra data suggested that antibiotic S1 was identical with Scopafungin, a 36-membered ring macrolide antibiotic. Antibiotic S1 showed potent antifungal activity against Candida albicans, Rhodotorula sp., and Aspergillus niger with MIC value of 0.234 µg/mL, 0.234 µg/mL, and 0.469 µg/mL, respectively.

Key words: Streptomyces castelarensis, isolation and purification, structure, scopafungin