Abstract: (S)-Hydroxynitrile lyases which have an improved substrate acceptance and which are derived from the Hevea brasiliensis and Manihot esculenta (S)-hydroxynitrile lyases, wherein one or more bulky amino acid residues within the hydrophobic channel leading to the active center have been replaced with less bulky amino acid residues.

Abstract: Process for the preparation of the (S)-enantiomers of optically active cyanohydrins, in which a reaction mixture of a) an aldehyde or ketone dissolved in an organic, water-immiscible or slightly miscible diluent, b) an aqueous (S)-hydroxynitrile lyase solution and c) a cyanide group donor is stirred in such a way that an emulsion is formed which is maintained up to the end of the reaction by stirring.

Abstract: Process for transesterifying &agr;-ketocarboxylic esters in an anhydrous alcohol as reaction medium in the presence of tin catalysts, titanium catalysts, zirconium catalysts or lithium catalysts or of acetylacetonates as catalysts.

Abstract: Process for the preparation of 2-acetylcarboxylic esters by reacting an acetoacetic ester having 1 to 6 C atoms in the alkyl moiety with an aliphatic aldehyde having 1 to 12 C atoms at 0 to 40.degree. C. in the presence of a condensation catalyst, subsequently removing the water of reaction formed and unreacted starting materials and then hydrogenating the material at 20-160.degree. C., the temperature in the first hydrogenation phase being between 20 and 90.degree. C. and the temperature in the second phase being increased to 50 to 160.degree. C., depending on the starting temperature.

Abstract: A process for stabilizing enantiomer-enriched cyanohydrins where citric acid and/or boric acid or boric anhydride is added as a stabilizer to the cyanohydrin to be stabilized.

Abstract: Intumescent sealing and cover profiles obtainable by extrusion of a mixture comprising thermoplastic elastomers, expandable graphite, flame retardants, inorganic fillers and inorganic fibers at from 180 to 250.degree. C. and subsequent shaping to form the appropriate profiles, and their use.

Abstract: A process for the purification of recovered or regenerated phosphorus oxychloride contaminated by reactive organic compounds, by reacting the contaminated phosphorus oxychloride with from 0.1 to 5% by weight of an organic amine, having 1 or 2 tertiary N-atoms and a boiling point above the boiling point of phosphorus oxychloride, at the boiling temperature of the reaction mixture and subsequently carrying out fractional distillation at atmospheric pressure to obtain purified phosphorus oxychloride.

Abstract: An improved process for preparing L-aspartic acid by enzyme-catalyzed reaction of fumaric acid with ammonia, in which, after reaction has been completed, excess ammonia is removed from the reaction mixture, L-aspartic acid is precipitated by adding acetic acid or formic acid, whereupon formic acid and acetic acid are rereleased from the mother liquor by adding fumaric acid, and the ammonia released and the liberated formic or acetic acid and the ammonium fumarate formed in the liberation are reused for subsequent cycles.

Abstract: Process for preparing glyoxylic esters or their hydrates in which a water-soluble salt of a maleic or fumaric monoester or a mixture thereof is reacted with ozone in aqueous solution at temperatures of from 0 to 50.degree. C., and the corresponding glyoxylic ester or its hydrate is isolated from the resulting reaction mixture.

Abstract: Process for the preparation of carboxylic acid succinimidyl esters by reaction of N-hydroxysuccinimide with a carboxylic acid and a halophosphoric acid ester of the formula ##STR1## in which R.sub.1 and R.sub.2 are identical or different and are a C.sub.2 - to C.sub.6 -alkyl radical or a phenyl radical, or R.sub.1 and R.sub.2 together form a C.sub.6 -aryl radical, in the presence of a base in a diluent at a temperature of 0.degree. C. up to 100.degree. C. and isolation of the corresponding carboxylic acid succinimidyl ester.

Abstract: A process for the preparation of disodium Z-L-aspartate from fumaric acid, in whicha) fumaric acid is reacted with ammonia in an inert diluent in the presence of aspartase or aspartase-producing microorganisms to give ammonium L-aspartate thenb) the ammonium L-aspartate-containing solution is treated with sodium hydroxide, forming, depending on the amount of sodium hydroxide used, the mono- or disodium L-aspartate or a mixture thereof, andc) the eliminated ammonia is returned to a fumaric acid suspension, which is used as starting solution for further enzymatic reactions, and thend) the residual mono and/or disodium L-aspartate-containing solution is reacted with benzyloxycarbonyl chloride at a pH of between 9 and 14, with the simultaneous addition of sodium hydroxide, to form disodium Z-L-aspartate.