UCS1025A, a novel antibiotic produced by Acremonium sp.

antimicrobial activity, and antiproliferative activity against humantumor cell lines. In this paper, we describe the taxonomy of the producing organism, fermentation, isolation, physico-chemical properties and biological activities ofUCS1025A and B. The cultural and taxonomical characteristics of the producing fungal strain KY4917 were as follows. Colonies on 2% malt extract agar medium are 28 to 31mmin diameter after culturing at 25°C for 2 weeks. The surface of the colony is grayish brown at the center and beige or grayish white at the margin. The color of the reverse of the colony is reddish brown at the center and grayish brown at the margin. Soluble orange pigment is produced in the medium. Colonies on Potato-glucose agar medium are about 25mm in diameter after culturing at 25°C for 2 weeks. The color of the colony surface is cream or pale brown at the center and gray at the margin. The color of the reverse of the colony is pale brown to brown at the center and grayish white at the margin. Smooth and colorless hyphae are developed on Potato glucose agar medium. The hyphae are septate and wellbranched. Conidia are produced at the tip of phialides developing from the hyphae. Typically forming single orthotropic phialides. Phialides are hyaline, smooth, 10 to