C37H62-66O17; mol wt about 780. A mixture of partially acylated derivatives of a di-d-glucosyldihydroxyhexadecanoic acid. Antibiotic substance produced by the corn smut fungus Ustilago zeae: Haskins, Can. J. Res. 28C, 213 (1950); Lemieux et al., Can. J. Chem. 29, 409, 415 (1951); Reed, Holder, Can. J. Med. Sci. 31, 505 (1953); Haskins, US 2698843 (1955 to National Research Council, Canada). Biosynthesis: Boothroyd et al., Can. J. Biochem. Physiol. 33, 289 (1955). Production by submerged culture: Lemieux, CA 600121 (1960 to National Research Council, Canada).