Phosphonomycin: isolation from fermentation sources.

Phosphonomycin, (-)-cis-l, 2-epoxypropylphosphonic acid, was isolated from fermentation sources as a crystalline calcium salt. Methods for ionexchange adsorption, ion-exchange chromatography using both anionand cation-exchange resins, gel-permeation chromatography, adsorption chromatography and solvent partition were investigated. The overall purification was about 5,000 fold with a yield of 12 %, Conditins for ion-exchange chromatography were developed based on batch equilibration studies. Thin-layer chromatography was used to develop a chromatographic procedure with alumina. The molecular weight estimated from gel-permeation studies was somewhat higher than the true value. A number of other salts which remained amorphous were also prepared.