Basf Aktiengesellschaft

Christoph Martin

Johannes Grimmer

Hardo Siegel

Hans Kiefer

Walter Himmele

Joachim Meyer

Werner Kuesters

Ernst-Heinrich Pommer

Walter Gramlich

Andreas Fischer

Dirk Franke

Bryan Cooper

Stefan Marcinowski

Tillmann Faust

Friedrich Hill

Wolfgang Buehler

Thomas Knebel

J&uuml;rgen M&uuml;ller

Georg Wellinghoff

Walter Gosele

Rolf Lungershausen

Gunter Eipper

The present invention relates to an improved process for preparing riboflavin of the B/C modification in granule form. Furthermore, the invention relates to the riboflavin preparation process wherein riboflavin of the A modification is (a) dissolved in aqueous mineral acid without treating the resulting riboflavin solution with activated carbon, (b) precipitated directly afterwards, steps (a) and (b) being carried out at a temperature in the range from 5 to 15&#xb0; C., and (c) dried by fluidized bed granulation; and wherein the riboflavin does not come into contact with the aqueous mineral acid solvent for longer than on average 4 hours.

Method for the production of riboflavin of modification b/c in granular form

A process is described for purifying an amino acid-containing solution by means of electrodialysis, wherein an amino acid-containing solution is employed which is obtained from the fermentation for producing at least one amino acid.

Method for purification of amino acid containing solutions by electrodialysis

A process for the stereoselective preparation of (-)3a,6,6,9a-tetramethylperhydronaphtho[2,1-b]furan of the formula Ia ##STR1## by dehydration and cyclization of decahydro-2-hydroxy- 2,5,5,8-tetramethyl-1-naphthaleneethanol using solid acidic catalysts, wherein the decahydro-2-hydroxy- 2,5,5,8-tetramethyl-1-naphthaleneethanol is heated in the molten state at from 80.degree. to 200.degree. C. in the presence of from 10 to 100% by weight, based on the diol, of an active acidic aluminum oxide commercially supplied for (preparative) column chromatography.

Stereoselective preparation of (-)

A process for preparing spray granules or microgranules, which contain no binder, are non-dusting and free-flowing, from finely divided pure riboflavin, comprises subjecting an aqueous or water-containing suspension of the pure finely divided riboflavin to

Spray granules or microgranules of pure riboflavin which contain no

A method of purifying ferment-produced riboflavin, wherein the impure riboflavin is suspended in water or dilute aqueous acid, and the suspension is heated at a temperature of from 75.degree. to 130.degree. C. for from 0.3 to 3 hours with stirring, during which time crystal transformation takes place, after which the mixture is cooled and the purified product is isolated in known manner.

Method of purifying ferment-produced riboflavin

Riboflavin is removed from fermentation suspensions by them being heated at from 50.degree. to 90.degree. C. for from 1 to 3 hours, than cooled to from 0.degree. to 30.degree. C. over a period of from 1 to 5 hours, and subsequently being centrifuged to give a sediment fraction and liquid fraction in such a way that the sediment fraction contains predominantly riboflavin crystals as solid, and the liquid fraction contains virtually no crystalline riboflavin, and, where appropriate, resuspending the sediment fraction in from 0.5 to 2 parts by volume of water per part by volume of sediment fraction and repeating procedure c.

Removal of riboflavin from fermentation suspensions

Riboflavin produced by a microbial method is prepared in the form of free-flowing, non-dusting, spray-dried granules or microgranules as a feed additive by removing water from the mixture discharged from microbial fermentation for the preparation of riboflavin, wherein the mixture is subjected to

Preparation of riboflavin, produced by a microbial method, in the form

A process for the preparation of optically pure D- or L-lactic acid by fermentation of an aqueous nutrient medium, which contains nitrogen, vitamins, aminoacids, sugars and trace elements, by means of a microorganism, at pH 4-6, wherein the nutrient medium contains brewers' yeast as the source of nitrogen, vitamins, aminoacids and trace elements.

Preparation of optically pure D- and L- lactic acid

Cyclohexene derivatives of the formula I ##STR1## where R.sup.1 and R.sup.2 are hydrogen or tert.-butyl and N and X are members of a heterocyclic ring in which X is an alkylene chain of four, five or six members, one of which may be a hetero-atom, such as oxygen, and where the alkylene radicals are unsubstituted or substituted by alkyl or by --CH.sub.2 OH or its acetyl or propionyl derivative, and their salts are used in fungicides.

Cyclohexene containing morpholines and fungicidal use

A process for the preparation of D-carbamyl-.alpha.-aminoacids of the formula ##STR1## where R has the meanings given in the description, by enzymatic cleavage of the corresponding hydantoins by means of thermophilic, non-sporulating hydantoin-cleaving micro-organisms or of extracts therefrom.

Preparation of D-N-carbamyl-.alpha.-aminoacids and micro-organisms for

S-Configurated phenylpropane derivatives of the formula ##STR1## where R.sup.1 is alkyl, aryl or alkoxy, R.sup.2 is hydrogen, alkyl, aryl or alkoxy, and R.sup.3 is carboxyl or esterified carboxyl, acetalized formyl, hydroxymethyl or esterified hydroxymethyl, their preparation by microbiological hydrogenation, and their use for the preparation of fungicidal compounds.

Growing community of inventors

Mannheim, Germany

Christoph Martin