Carbomycinis a colorless, optically active crystalline macrolide antibiotic with the molecular formula C42H67NO16. Carbomycin can be isolated from Streptomyces halstedii via extraction from a fermentation broth and purified through crystallization from alcohol-water mixtures. Carbomycin can be further purified with the use of preparative thin layer chromatography. The most efficient solvent is one consisting of ethanol-hexane-water in 90-10-0.15 volume ratio. In the biosynthesis of carbomycin by Streptomyces halstedii, when soybean meal is used to ferment the antibiotic, the addition of several substances can increase the yield of carbomycin. When blackstrap molasses, a carbon source, is added, an increased yield is observed. Nitrogen sources ammonium chloride, ammonium nitrate, and ammonium dihydrogen phosphate have the same effect on the production of carbomycin.