Abstract: The invention relates to a process for the immobilization of compounds comprising nucleophilic groups.According to the process of the invention a polymer comprising an amido group is swollen in a buffer. For this purpose any buffer is suitable which contains no amino, sulfhydryl and/or hydroxy groups in the molecule. To the swollen polymer a solution of a quinone - preferably p-benzoquinone - in a water miscible organic solvent is added and the mixture is activated at 273.degree.-343.degree. K. for 0.5-48 hours - preferably for 24 hours. The unreacted quinone is washed out with an aqueous solution of a water miscible organic solvent and thereafter water and/or a buffer. To the purified gel at a pH value between 3 and 11 - preferably between 6 and 8 - a buffered solution of a compound comprising a nucleophilic group is added, the suspension is incubated at 260.degree.-313.degree. K. for 24 hours, the gel is separated and the non-bound compound comprising a nucleophilic group is removed by washing.

Abstract: Immobilized aminoacylase having high specific activity is obtained by covalent bonding of aminoacylase to a partially hydrolyzed Akrilex P type acrylamide-N,N.sup.1 -methylene-bis (acrylamide) copolymer. Covalent bonding is carried out by partially hydrolyzing the copolymer with a base or an acid to form carboxy groups, activating the carboxy groups with a carbodiimide and coupling aminoacylase to the activated carboxy groups. The aminoacylase may be isolated from mammal kidneys by forming an aqueous kidney extract, heat treating the extract and isolating aminoacylase from the heat treated extract.

Abstract: The invention relates to a process for the preparation of a cyclodextrine glycosyltransferase enzyme.The immobilization can be carried out by two methods. According to the first method a cyclodextrine glycosyltransferase enzyme is activated with a solution of a carbodiimide compound and the thus treated enzyme is applied in a solution having a pH value of 4.5-8.5 onto a polysaccharide derivative comprising at least 0.1 m-equiv./g of free amino group. According to the second method the enzyme is applied in a solution having a pH value of 4.5-8.5 onto a polymer produced from an acrylic acid and/or methacrylic acid or acrylic amide and/or methacrylic amide monomer by means of a cross-linking agent of the acrylic or allylic type which polymer comprises at least 0.1 m-equiv./g of functional carboxy group, activating the polymer with a solution of a carbodiimide compound and washing and if desired drying the product thus obtained.

Abstract: Aminoacylase is isolated from mammal kidneys by comminuting and homogenizing mammal kidney in water, centrifuging to form an aqueous extract, heating the aqueous extract at 60.degree. to 80.degree. C. for 5 to 15 minutes, centrifuging, adding a salt such as ammonium sulfate to the resultant supernatant, centrifuging to separate solids, dissolving the solids in water, dialyzing and recovering active aminoacylase from the dialyzed solution. The process produces aminoacylase with high specific activity and the process requires fewer purification steps. The aminoacylase obtained may be utilized directly without any subsequent purification to produce immonobilized aminoacylase. Immobilization can be carried out by covalent bonding of the aminoacylase to a partially hydrolyzed Akrilex P type acryl amide-N,N'-methylene-bis(arylamide) copolymer. The recovered aminoacylase can be subjected to two chromatographic purification steps to produce a very pure aminoacylase.

Abstract: The invention relates to a new method for the preparation of N-aryl-N'-(mono- or disubstituted)-urea derivatives having the general formula (I), ##STR1## wherein Aryl is an optionally substituted phenyl group, andR.sup.1 and R.sup.2 each stand for an optionally substituted alkyl, cycloalkyl, alkoxy or phenyl group, orR.sup.1 and R.sup.2 may form, together with the adjacent nitrogen atom, a nitrogen-containing heterocyclic group which may contain a further hetero atom, orone of R.sup.1 and R.sup.2 may also stand for hydrogen,with the proviso that if one of R.sup.1 and R.sup.2 is an optionally substituted phenyl group, the other may represent only hydrogen atom or an optionally substituted alkyl or alkoxy group,by reacting a carbamate of the general formula (II) with an amine of the general formula (III),R.sup.1 R.sup.2 N--CO--X (II)Aryl--NH.sub.2 (III)or a carbamate of the general formula (IV) with an amine of the general formula (V),Aryl--NH--CO--X (IV)R.sup.1 R.sup.2 NH (V)wherein R.sup.1, R.sup.