摘要:
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.
摘要:
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(a) a fluidized-bed spray-drying process(b) a one-material spray-drying process or(c) a disk spray-drying process without significant amounts of binders being added to the discharged fermentation mixture.
摘要:
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.
摘要:
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 toa) a fluidized bed spray dryingb) a single-nozzle spray drying orc) a disk-type spray dryingin particular a fluidized bed spray drying, without adding binders to the suspension, and the spray granules or microgranules of riboflavin obtainable by this process.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
The present invention relates to an improved process for preparing pure riboflavin (vitamin B2) of the B/C modification in granule form. Furthermore, the invention relates to pure riboflavin in granule form which has a bulk density to be determined in accordance with DIN 53468 of from 0.45 to 0.7 g/ml and, after tableting, has a dissolution of at least 80%.