Abstract:

An antimicrobial factor termed AF1 was isolated from culture broth of Penicillium griseoroseum. The filtered fermentation broth underwent centrifugation and ultrafiltration (membrane cutoff 5?kD). Then it was purified using Sephadex LH20 and highperformance liquid chromatography (HPLC). The molecular weight of AF1 was 1465 Da. AF1 was stable to βlactamase, hydroxylamine, acid, alkali and heat. Together, these data indicate that AF1 is a novel antibacterial factor which is different from penicillin. The molecular structure of AF1 shows characteristics of saccharide and amid. MIC of AF1 versus Staphylococcus aureus is 80?μg／ml, and AF1 is effective to drugresistant S. aureus. It is difficult to induce bacterial resistant to AF1.

Key words: Penicillium;　antibiotic; isolation; characteriza tion