Effective biosynthesis of benzoyl‐pyrrothine dithiolopyrrolone antibiotic by cinnamic acid‐precursor addition in culture of Saccharothrix algeriensis NRRL B‐24137

Dithiolopyrrolone antibiotics, produced by several micro‐organisms, are known for their strong antimicrobial and antitumor activities. Among of this micro‐organisms, Saccharothrix algeriensis NRRL B‐24137, a rare actinobacterium, has the ability to produce several dithiolopyrrolones derivatives depending on precursors added in the culture medium. After 10 days of strain fermentation on semi‐synthetic medium supplemented with cinnamic acid and HPLC purification, biosynthesis of benzoyl‐pyrrothine dithiolopyrrolone was evidenced through complete spectroscopic (UV–visible and 1H and 13C NMR) and spectrometric (electron impact mass spectrum) analyses. The pure molecule showed appreciable minimum inhibitory concentration values against several Gram‐positive bacteria and filamentous fungi