Antibiotic TKR2999 having the following physicochemical properties: (1) the m/z value ([M+H] ) is 971 as determined by FAB mass spectrometry, (2) the molecular formula is C44H78N10O14 and the m/z value ([M+H] ) is 971.5776 as determined by high-resolution FAB mass spectrometry, (3) the ultraviolet absorption spectrum (as determined in methanol) has a terminal absorption, (4) the main absorption wavenumbers (cm ) of infrared absorption spectrum (as determined by the KBr method) are 3320, 2920, 1680, 1540, 1210, 1140, 840, 800 and 720, (5) aspartic acid, threonine, serine, glycine, alanine, beta -alanine and ornithine are detected in the amino acid analysis based on the ninhydrin reaction, and (6) it is soluble in methanol but difficultly soluble in hexane, chloroform and water; or pharmacologically acceptable salts thereof. These novel substances are useful as remedies for mycosis.