从 Streptomyces aureofaciens 培养液中分离出新的多肽类抗肿瘤抗菌素 Macracimycin[Ⅰ]。[Ⅰ]的产生菌进行振荡培养,发酵液稀释16倍对接种艾氏腹水瘤的小鼠存活期延长三倍以上。调节滤液的 pH 至7.0,用50%饱和的硫酸铵反复沉淀。沉淀物对 Tris—HCl 缓冲液透析,然后冷冻干燥,得褐色粉末状[Ⅰ]的粗制品。它对艾氏腹水瘤最小有效量为62.5微克/鼠/天。 A new peptide antitumor antibiotic Macracimycin [Ⅰ] was isolated from Streptomyces aureofaciens. [I] producing bacteria were shaken culture, fermentation broth 16-fold dilution of Ehrlich ascites inoculated mice survival longer than three times. The filtrate was adjusted to pH 7.0 and repeatedly precipitated with 50% saturated ammonium sulfate. The precipitate was dialyzed against Tris-HCl buffer and then lyophilized to obtain a crude product of [I] as a brown powder. Its minimum effective dose of Ehrlich ascites tumor is 62.5 micrograms / mouse / day.