Selective production of l-phenylserine isomers by shmt

Abstract From the Canadian patent

L-serine derivatives produced by the enzyme catalyzed aldol condensation of glycine and an aldehyde in aqueous solution are recovered in high yield by extracting the aqueous product solution containing said serine derivatives with an organic phase comprising (i) an aldehyde, or (ii) mixtures of an aldehyde and a water immiscible organic solvent, followed by re-extracting the organic phase with an aqueous phase having a pH of less than about 7Ø The L-erythro isomers of L-serine derivatives such as L-phenylserine may be preferentially prepared by the use of this extraction/re-extraction procedure in combination with bioreactor reaction conditions which include a pH of from about 7.5 to 10, an …