[Mass spectrophotometric study of the antibiotic granaticin]

A culture of Streptomyces sp. producing a substance with antibacterial and antitumor activity was isolated from a soil sample collected in the Gorno-Altai Autonomous Province. By its UV, NMR and mass spectra the antibiotic was identified as granaticin. Mass spectral disintegration of granaticin was studied in detail: mass spectra of electron impulse (including that of high performance), field desorption, chemical ionization of positive and negative ions. Correlation relationship between directions of fragmentation of the molecular and basic moiety ions and fragments of the antibiotic structure was derived. Specific peaks of the ions providing mass spectrometric identification of the antibiotic in various natural mixtures were detected.