Procedure for isolation of Thienamycin from fermentation broths

An improved process for the isolation of thienamycin, produced by the actinomycete Streptomyces cattleya , has been developed. The isolation procedure consists of three chromatographic steps, volume reduction by reverse osmosis between the steps, and freezedrying for obtaining the final product. The chromatographic steps are as follows: (1) ion exchange chromatography on Dowex 1 × 2 resin in the bicarbonate cycle, (2) gel chromatography on Dowex 1 × 2 resin in the chloride cycle, (3) reverse phase chromatography on XAD‐2 resin. This procedure is useful for processing large volumes of fermentation broth.