关键词: 保罗霉素, 结构鉴定, 稳定性, 抗菌活性

Paulomycins are a group glycoside antibiotics produced by Streptomyces, which not only show excellent antibacterial activities against gram-positive bacteria, but also display good antitumor activities. The paulic acid moiety is one of the structures that cause the instability of paulomycin. This study aimed to improve the stability of paulomycins. When small molecule thiol compound N-acetylcysteamine (SNAC) was added to the fermentation broth of paulmycin producing strain, four new paulomycin derivatives of palsimycins A, B, C, and D were obtained. The antibacterial activity evaluation showed that the minimal inhibit concentrations (MICs) of palsimycin A and palsimycin B against the tested strains were at the same level as those of paulomycin A and paulomycin B. The stability test revealed that under the same conditions, palsimycin A, B, C, and D were all more stable than paulomycin A and paulomycin B. In conclusion, without scarifying the antibacterial activity, this study increased the stability of paulomycin by the addition of paulic acid with SNAC, which laid a foundation for further research and application of paulomycins.

Key words: paulomycin, structure identification, stability, antibacterial activity