Abstract: A coupled enzyme reaction of a transaminase with GOT activity and of a transaminase with L-phosphinothricin transaminase activity produces phosphinothricin in virtually quantitative yield and virtually without any contamination whatever by a natural amino acid when the amino donor glutamate is employed in catalytic amounts and the amino donor aspartate is employed in approximately equimolar amounts relative to 4-(hydroxymethylphosphinyl)-2-oxobutyric acid.

Abstract: L-PTC (L-phosphinothricin, L-2-amino-4-methylphosphino-butyric acid) is the active herbicidal component of D,L-PTC and can be obtained according to the invention when D,L-PTC derivatives which are N-acylated and esterified on the phosphinic acid group as well as optionally esterified or amidated on the carboxylic group, are treated with a hydrolytically active enzyme in an aqueous or aqueous-organic medium, in which process the L-PTC derivatives are selectively hydrolyzed on the N-acyl group or the modified carboxyl group, the resulting product mixture is resolved, and the desired L-PTC derivative is hydrolyzed to give the L-PTC and isolated by customary methods.

Abstract: L-PTC (L-phosphinothricin, L-2-amino-4-methylphosphino-butyric acid) is the active herbicidal component of D,L-PTC and can be obtained according to the invention when D,L-PTC derivatives which are N-acylated and esterified on the phosphinic acid group as well as optionally esterified or amidated on the carboxylic group, are treated with a hydrolytically active enzyme in an aqueous or aqueous-organic medium, in which process the L-PTC derivatives are selectively hydrolyzed on the N-acyl group or the modified carboxyl group, the resulting product mixture is resolved, and the desired L-PTC derivative is hydrolyzed to give the L-PTC and isolated by customary methods.

Abstract: Process for the enzymatic resolution of 2-amino-4-methylphosphinobutyric acid derivatives.L-PTC (L-phosphinothricin, L-2-amino-4-methylphosphinobutyric acid) is the active herbicidal component of D,L-PTC and can be obtained according to the invention when D,L-PTC derivatives which are N-acylated and esterified on the phosphinic acid group as well as optionally esterified or amidated on the carboxylic group, are treated with a hydrolytically active enzyme in an aqueous or aqueous-organic medium, in which process the L-PTC derivatives are selectively hydrolyzed on the N-acyl group or the modified carboxyl group, the resulting product mixture is resolved, and the desired L-PTC derivative is hydrolyzed to give the L-PTC and isolated by customary methods.

Abstract: In the enzymatic stereoselective ester cleavages of 2-arylpropionate, the reaction rate of the hydrolyzing enzymes can be drastically increased if the vinyl ester of the 2-arylpropionate is employed as the substrate.

Abstract: The O-acylation of alcohols is carried out by reacting a vinyl ester or a carboxylic ester with Pseudomonas lipase immobilized on a hydrophobic carrier such as a polystyrene-based carrier. The polystyrene carrier preferably has a surface area of 100-1000 m.sup.2 /g, a pore volume of 25 to 75% and a pore diameter of 25-1200 .ANG.. Crosslinking may be carried out after the lipase is immobilized on the carrier.

Abstract: In the enzymatic stereoselective ester cleavages of 2-arylpropionate, the reaction rate of the hydrolyzing enzymes can be drastically increased if the vinyl ester of the 2-arylpropionate is employed as the substrate.

Abstract: Racemic alcohols can be resolved in good yield and with high enantiomeric purity in the presence of vinyl esters with the aid of lipases from pig pancreas, pig liver and microorganisms.