Compositions and methods for the production of L-glufosinate are provided. The method involves converting racemic glufosinate to the L-glufosinate enantiomer or converting PPO to L-glufosinate in an efficient manner. In particular, the method involves the specific amination of PPO to L-glufosinate, using L-glutamate, racemic glutamate, or another amine source as an amine donor. PPO can be obtained by the oxidative deamination of D-glufosinate to PRO (2- oxo-4-(hydroxy(methyl)phosphinoyl)butyric acid) or generated via chemical synthesis. PPO is then converted to L-glufosinate using a transaminase in the presence of an amine donor. When the amine donor donates an amine to PPO, L-glufosinate and a reaction by product are formed. Because the PPO remaining represents a yield loss of L-glufosinate, it is desirable to minimize the amount of PPO remaining in the reaction mixture. Degradation, other chemical modification, extraction, sequestration, binding, or other methods to reduce the effective concentration of the by-product, i.e., the corresponding alpha ketoacid or ketone to the chosen amine donor will shift the reaction equilibrium toward L-glufosinate, thereby reducing the amount of PPO and increasing the yield of L-glufosinate. Therefore, the methods described herein involve the conversion or elimination of the alpha ketoacid or ketone by-product to another product to shift the equilibrium towards L-glufosinate.L'invention concerne des compositions et procédés de production de L-glufosinate. Le procédé implique la conversion du glufosinate racémique en l'énantiomère de L-glufosinate ou la conversion de PRO en L-glufosinate d'une manière efficace. En particulier, le procédé implique l'amination spécifique de PRO en L-glufosinate, à l'aide de L-glutamate, de glutamate racémique, ou d'une autre source d'amine en tant que donneur d'amine. Le PRO peut être obtenu par désamination oxydative de D-glufosinate en PRO (acide 2-oxo-4-(hydroxy(méthyl)phosphinoyl butyrique) ou g
