Izumenolide-a novel beta-lactamase inhibitor produced by Micromonospora. I. Detection, isolation and characterization

Micromonospora chalcea subsp. izumensis produces a novel beta-lactamase inhibitor izumenolide (EM4615). Isolation of izumenolide was performed by extraction into butanol under acidic conditions and then back extraction into water at neutrality. The compound was precipitated from the aqueous phase by the addition of calcium or barium salts. Further purification was achieved by distribution in BuOH - 1 N NaOH. Izumenolide is a macrolide containing sulfate ester groups.