Meleumycin is a multi-component mixture mainly containing midemycin A1 and kitasamycin A6. It is white or off-white powder or crystalline powder; slightly smelly; bitter taste. It is very soluble in methanl, very slightly soluble in water, and insoluble in petrolem ether. It is a multi-component macrolide antibiotic produced by Streptomyces. The antibacterial performance is similar to that of erythromycin. It has strong antibacterial effect on gram-positive bacteria and mycoplasma. It also has antibacterial effect on some gram-negative bacteria such as Neisseria meningitidis and Neisseria gonorrhoeae. Some erythromycin-resistant Staphylococcus aureus can still be sensitive to this product. This product acts on the 50S subunit of the bacterial ribosome to hinder the synthesis of bacterial protein. It is a bacteriostatic agent during the growth period.