Glomosporin, a Novel Antifungal Cyclic Depsipeptide from Glomospora sp. I. Production, Isolation, Physico-chemical Properties and Biological Activities

A novel antifungal cyclic depsipeptide termed glomosporin, which has a fatty acyl side chain, was isolated from a barley solid culture of Glomosporasp. The strain was isolated from fallen pine leaves collected in Fukusima Prefecture, Japan and identified as Glomospora sp. BAUA 2825. Glomosporin was purified by butanol extraction followed by preparative HPLC. Glomosporin showed antimicrobial activity against fungi including clinically important A spergillus fum iga tus. The incidence of fungal infection is still increasing. Amphotericin B, which was discovered several decades ago, has manysevere side-effects, but is still used as one of the main therapeutical agents for fungal infections, especially thouse caused by Aspergillus fumigatus. It is clear that we need a new antifungal agent with a low toxicity, active against the clinically important fungus, Aspergillus fum igatus. During the course of a screening program for novel antifungal agents from secondary metabolites of fungi grown on a solid barley medium, we discovered a novel compoundnamed glomosporin (Fig. 1) from a culture of Glomospora sp. BAUA2825. In this communication, we report the production, isolation, physico-chemical properties and biological activities of glomosporin. The producing strain is Glomospora sp. ^ which is the second instance of isolated genus reported so far. Detailed studies on taxonomy of the strain will be published separately2). Structure elucidation of the compoundis described in an accompanying paper3). pp.597 _ 60