Abstract: At least one acryl or allyl monomer is polymerized in an aqueous suspension containing a fumarase-producing microorganism. The resultant immobilized fumarase-producing microorganism is contacted with bile acids or salts thereof. Then, the immobilized fumarase-producing microorganism is subjected to enzymatic reaction with fumaric acid or a salt thereof. L-Malic acid is prepared without the production of the by-product succinic acid.

Abstract: An immunoassay method utilizes antigen tagged, enzyme encapsulating liposomes which are immunospecifically ruptured in the presence of cognate antibody and active complement. A homogeneous phase reaction occurs with the antibody and complement acting to release the enzyme if an immunospecific antigen-antibody complex is formed at the surface of the liposome. The positions of the antigen and antibody can be reversed.

Abstract: Disclosed herein is a process for the enzyme-catalyzed conversion of ethanol to acetaldehyde utilizing tris (hydroxy-methyl) aminomethane as a buffering and complexing agent. The process is particularly useful for bringing about the in situ oxidation of ethanol, contained in a fruit essence, to acetaldehyde.

Abstract: Ethanol is produced by culturing the microorganism Kluyveromyces cellobiovorus or Kloeckera apiculata in a medium containing, as a carbon source, an assimilable source of xylose, cellobiose or both. The carbon source may be provided in the form of hydrolysates of cellulose containing substances such as cotton, wood, straw or paper which are obtained by acid hydrolysis or enzymatic action. At the completion of culturing, ethanol is removed from the culture in a conventional manner.

Abstract: An improvement in assaying methods involving biospecific affinity reactions, in which there are used from 2 to 4 reactants, one of which, reactant (I), is labelled with at least one analytically indicatable atom or group and is soluble in the aqueous liquid in which the biospecific affinity reaction is carried out, the reactants forming, by means of biospecific reactions, a conjugate in which labelled reactant (I) is incorporated; and in which assaying methods the analytically indicatable atom or group is assayed in the conjugate and/or in labelled reactant (I), which is not bound to the conjugate. The conjugate that has been formed or labelled reactant (I) not bound to the conjugate is bound covalently to an insoluble carrier or to an insolubilizable carrier, which latter carrier is made insoluble after the covalent binding has been carried out, whereafter the assay of the analytically indicatable atom or group is carried out.

Abstract: A solution of an active protein substance and an inactive protein substance is reacted with a cross-linking agent, optionally in the presence of an inert carrier, under cross-linking conditions to produce articles comprising both active and inactive protein substances. The active protein substance comprises up to about 20 percent, e.g. from 1 to 20 percent by weight, based on the final weight of the total protein substance, whereas the cross-linking agent comprises from 0.5 to 8 percent by weight, based on the weight of the total treated mixture. The obtained articles are in the form of a solution or a suspension in aqueous medium, in the form of a film, in the form of a membrane, in the form of a fabric, in the form of a porous material, or in the form of a mass, such as granules, pills or tablets.

Abstract: A process for the preparation of an enzymatically active formulation embedded in silica gel, wherein an aqueous mixture of an enzymatically active formulation and a dissolved alkali metal silicate and/or ammonium silicate is suspended in an organic, water-immiscible fluid and then converted to a water-insoluble gel.

Abstract: Foams having aspartase-producing microorganisms bound to the foam are made from polyurethane prepolymers which are capped with polyisocyanates, including diisocyanates, derived from methylene-bis (phenyl isocyanate) which is commonly known as MDI. These MDI based foams are hydrolysis resistant as compared to the previously used TDI based foams. The foams can be used to produce L-aspartic acid under high pH conditions.

Abstract: The instant invention is directed to a process for the production of denatured polyaddition products of biomasses and isocyanates, comprising reacting(A) from 5 to 98%, by weight, based on (A)+(B), of a biomass based on microorganisms or derivative and decomposition products thereof with(B) from 95 to 2%, by weight, based on (A)+(B), of a compound containing isocyanate groups, at temperatures of at least 50.degree. C. with complete denaturing of component (A).

Abstract: Biologically active material is immobilized by forming a gel precursor containing the biologically active material, a polymerizable material and a viscosity enhancing agent, applying the gel precursor to a support material and gelling the gel precursor by polymerization to form a hydrogel containing the biologically active material on the support material. A least some of the hydrogel is enmeshed with the support material. By use of the viscosity enhancing agent, the gel precursor is provided with preferred rheological properties.

Abstract: Microorganisms are immobilized by adding microorganism cells to an aqueous solution of a mixture of a polymerizable starch and a polymerizable monomer, and, thereafter, polymerizing the polymerizable starch and polymerizable monomer, to prepare a polymer gel with microorganism cells enclosed therein. The polymerizable starch is prepared by introducing an acrylamidomethyl group into starch. The polymer gel has high mechanical strength and can be used repeatedly over long periods of the time while maintaining at high levels the reactivity of the microorganism enclosed therein.

Abstract: Enzyme-containing cells immobilized in an alginate gel are stabilized by contacting the gel with glycerol in a ratio of cellstoglycerol of 2:1 to 1:5. The enzyme-containing cells preferably convert sucrose to isomaltulose.

Abstract: A process for the continuous production of acrylamide or methacrylamide from acrylonitrile or methacrylonitrile by use of a microorganism capable of promoting the hydration of acrylonitrile or methacrylonitrile into the corresponding amide.Said process comprising immobilizing the microorganism or enzyme extracted therefrom, continuously bringing the acrylonitrile or methacrylonitrile into contact with the immobilized microorganism or enzyme in at least one reactor containing an aqueous medium at a pH pf 6 to 10 to cause the hydration reaction, and recycling a part of the reacted solution to dilute the unreacted acrylonitrile or methacrylonitrile and water therewith.

Abstract: Methods for microbiological processing of organic materials for production of valuable products. Asymmetric hollow fibers are employed in a flow reactor, where the hollow fibers have a semipermeable membrane surrounding a lumen, where the semipermeable membrane is supported by a sponge structure. The pores of the sponge structure serve as a housing for microorganisms or cells with high density packing of the microorganisms or cells in the pores. Nutrient medium continuously flowing through the lumen provides nutrients to the microorganisms or cells as well as any substrates to be processed by the microorganisms or cells. The nutrients and substrates diffuse through the semipermeable membrane into the pores, where they are processed, and the metabolic products diffuse into the lumen. The lumen effluent is then processed for the desired products. Optionally, oxygen is provided external to the hollow fiber to enhance the amount of oxygen available to the microorganisms and cells.

Abstract: Test strip for the dip and read colorimetric determination of substances dissolved in liquids. Such strips are composed of an inert supporting base covered with a layer of polymer beads in which the reagents are incorporated. The color reaction takes place within the beads themselves which improves sensitivity and reproducibility of the testing.

Abstract: Microbial cells having L-aspartase activity are immobilized for producing L-aspartic acid. The cells are immobilized by mixing the cells with a curable prepolymer material and curing the prepolymer material to form a crosslinked polymer. Suitable prepolymer materials are polyazetidine prepolymers, carboxymethyl cellulose which can be crosslinked with polyvalent ions, polyurethane hydrogel prepolymers and polymethylene isocyanates. A preferred prepolymer material is polyazetidine prepolymer. The polymer may be formed as a coating on a solid inert carrier.

Abstract: Biological materials are immobilized within condensed polyalkyleneimine polymers. Condensation of the polymer is accomplished by bridging the amine groups of polyalkyleneimine polymer chains with a polycarboxylic acid, in the presence of a condensing agent.

Abstract: An immobilized enzymatic active substance having an improved stability of enzymatic activity is prepared which comprises an enzymatic active substance such as microbial cells entrapped within a gel matrix of an unsubstituted amino, monoalkylamino or dialkylamino group-introduced polysaccharide having not less than 10 w/w % of sulfate moiety in the molecule thereof such as carrageenan. The immobilized enzymatic active substance is prepared by admixing the enzymatic active substance and an aqueous solution of the polysaccharide and then allowing to form a gel of the polysaccharide.

Abstract: The invention relates to a method for the preparation of discrete particles containing a biologically active substance comprising discrete particles of support material having immobilized in the pores thereof a biologically active substance (e.g. an enzyme). The method includes precipitating a biologically active substance in the pores of the particles of support material, by use of a precipitating agent comprising or including a water miscible organic liquid, and treating the biologically active substance precipitated in the pores to cause cross-linking so as to immobilize biologically active substance in the pores of the particles or porous support material.

Abstract: A process is described for producing acrylamide from acrylonitrile using an immobilized microorganism containing gel, which comprises immobilizing a microorganism having nitrilasic activity with a cationic acrylamide-based polymer gel and bringing acrylonitrile into contact with the immobilized microorganism gel in an aqueous medium containing substantially no salt.

Abstract: A contiguous multilayer membrane for use with an electrochemical sensor is prepared comprising a first relatively nonporous dense polymer layer, a second polymer layer less dense and more porous than the first layer, a third layer containing an enzyme and a fourth polymer layer less dense and more porous than the first layer. The polymer is preferably cellulose acetate and the second and fourth layers are prepared with a solvent and nonsolvent for the polymer. The membrane may contain multiple enzyme layers separated by a polymer layer. The multilayer membrane provides advantages of higher substrate conversion, homogeneous distribution of enzyme and/or minimized interference with analyte diffusion.

Abstract: Cell-free enzymes are immobilized by mixing the enzymes with a starch sol or a partially gelled starch gel to form a mixture containing preferably 20 to 60% starch, gelling the mixture, extruding the gelled mixture to form strands, drying the strands and breaking the dried strands into pieces to form shaped structures having improved mechanical strength.

Abstract: A membrane for electrochemical analysis is described comprising a first, relatively dense and thin layer and a second, relatively porous thick layer, which thick layer has dispersed therethrough the enzyme, glucose oxidase. The process of making the membrane by casting two to three layers of cellulose acetate compositions is also described.

Abstract: A process for producing acrylamide from acrylonitrile by utilizing a microorganism or enzyme capable of hydrating acrylonitrile into acrylamide in the form of a highly concentrated aqueous solution of acrylamide which comprises bringing acrylonitrile in contact with the microorganism or enzyme in an aqueous medium at a pH of from 6 to 10, at a temperature of from the freezing point to 50.degree. C., and under such conditions that the concentration of acrylamide in the reaction solution after the completion of the reaction is from 5% by weight to less than 20% by weight, and concentrating the resulting reaction solution; this invention further includes an embodiment wherein the reaction solution is concentrated by cooling the reaction solution after the reaction to from -4.degree. C. to -9.degree. C. to crystallize ice, separating the ice, and using the ice so separated for cooling during the hydration reaction.

Abstract: Disclosed is a system and process for producing substances produced in cells such as antibodies and biological response modifiers. Cells which produce the substance of interest are encapsulated within semipermeable membranes having an upper limit of permeability sufficient to allow traverse of ions, amino acids and other cell nutrients and then suspended in a culture medium. Serum components or other high molecular weight materials needed for ongoing viability and normal in vitro metabolism of certain types of cells may be included within the intracapsular volume and may be excluded from the extracapsular medium by limiting the permeability of the membranes. The substance of interest collects either in the intracapsular volume or the extracapsular medium, depending on the degree of permeability of the membranes and on the molecular weight of the substance.

Abstract: An immunoadsorbent material comprising inactivated, protein-A bearing Staphlococcus aureus immobilized in a polymeric matrix is used to remove IgG immunoglobulins and immune complexes from whole blood.

Abstract: Disclosed is a process for microencapsulating a core material and subsequently releasing the core material by selectively disrupting the membranes of the microcapsules. The encapsulation technique involves the formation of a semipermeable membrane, e.g., around a droplet, through the formation of multiple ionic salt bonds between a polyionic polymer in the droplet and a crosslinking polyionic polymer which possesses multiple ionic groups of opposite charge. The membrane can be selectively disrupted by exposing it first to a solution of competing crosslinking multivalent (preferably di or trivalent) ions followed by a solution of a competing polyionic polymer of the same charge as the polymer in the original droplet. Alternatively, a mixed solution of the two competing solutions may be used together. For example, a membrane comprising anionic alginate salt bonded to cationic polymer can be selectively disrupted by exposing the membrane to a mixed solution of monatomic, multivalent cations, e.g.

Abstract: Enzyme preparations are obtained from Aspergillus phoenicis having high inulinase activity, a very low Michaelis constant, thermal stability, optimum inulinase activity across a wide pH range, and little sensitivity to heavy metal ion inhibition. The enzyme may be immobilized on an organic macroporous polymer or in an alginate gel.

Abstract: Tissue cells such as islet of Langerhans cells or liver cells are encapsulated within a spheroidal semipermeable membrane comprising a polysaccharide having acidic groups cross-linked with a polymer having a molecular weight greater than 3,000. The cells within the microcapsules are viable, healthy, physiologically active and capable of ongoing metabolism. The encapsulated cells are useful for implantation in a mammalian body to produce substances and effect chemical changes characteristic of the cells in vivo tissue.

Abstract: Palatinose is produced from sucrose with an immobilized bacteria containing alpha-glucosyl transferase. The bacteria is immobilized by entrapping cells of the bacteria in calcium alginate gel granules and treating the granules with polyethyleneimine and glutaraldehyde. Palatinose is efficiently produced by packing the bacteria-containing granules in a column and passing a sucrose solution through the column at high velocity.

Abstract: Electrochemical method for determining the concentration of a carbon source and L-amino acid in a fermentation medium or cultured broth by contacting a microbial electrode consisting of an oxygen-sensitive electrode or a carbon dioxide gas-sensitive electrode combined with fixed microbial cells of a microorganism capable of assimilating said carbon source or decarboxylating said L-amino acid with a sample solution and sensing electrically the rate of current decrease which is caused by the consumed oxygen in the solution in proportion to the concentration of carbon source; or the electric motive force which is caused by the liberation of carbon dioxide in the sample solution in proportion to the concentration of L-amino acid. Microbial electrodes and systems useful in carrying out the aforementioned method are disclosed.

Abstract: A core material such as living tissue, individual cells, hormones, enzymes or antibodies is encapsulated in a semipermeable membrane that is permeable to small molecules for contact with the core material but is impermeable to potentially deleterious large molecules. Encapsulation may be carried out by suspending the core material in an aqueous medium containing a water soluble gum that can be reversibly gelled, forming the suspension into droplets, contacting the droplets with a solution of multivalent cations to gel the droplets as discrete, shape-retaining, water insoluble temporary capsules and cross-linking a surface layer of the temporary capsules to produce a semipermeable membrane around the capsules. Optionally the gel within the membrane may be reliquified by removing multivalent cations from the gel.

Abstract: Ethanol is produced in high concentration of 75 mg/ml or above such as 200 mg/ml by using an immbolized ethanol-producing microorganism to convert sugar to ethanol in a nutrient culture broth containing not more than 100 mg/ml sugar until the concentration of sugar is not more than 20% of its initial concentration, then adding a fresh culture broth containing not less than 100 mg/ml sugar and converting sugar to ethanol with the immobilized microorganism to produce the desired high concentration of ethanol. The microorganism is preferably immobilized in a sulfated polysaccharide gel as a dense layer near the surface of the gel.

Abstract: Microorganisms are immobilized by mixing the microorganisms with an aqueous solution of kappacarrageenan and gelling the resultant mixture by the addition of an epihalohydrin: alkylene polyamine polymer having a mole ratio of from about 0.60:1 to 2.7:1 and a molecular weight of from 4,000 to 50,000 or by the addition of polyethyleneimine having a molecular weight of 300 to 50,000. Preferred microorganisms are Aspergillus niger and Saccharomyces cerevisiae which are respectively used to produce citric acid and ethanol.

Abstract: An oxygen carrier, capable of reversibly binding and releasing oxygen, immobilized in a polymer matrix and a method of recovering dissolved oxygen from fluids utilizing the same.

Abstract: To chemically bind either impure or purified enzymes to polyurethane to produce insolubilized bound enzymes which are still enzymically active and which may be more stable than the original enzyme, and which can be reused without appreciable activity loss and whose physical characteristics can be varied depending on the application for which they are intended.

Abstract: An immunoassay method utilizes antigen tagged, enzyme encapsulating liposomes which are immunospecifically ruptured in the presence of cognate antibody and active complement. A homogeneous phase reaction occurs with the antibody and complement acting to release the enzyme if an immunospecific antigen-antibody complex is formed at the surface of the liposome. The positions of the antigen and antibody can be reversed.

Abstract: Enzyme immobilization is carried out be adding to a suspension of polysaccharide in aqueous medium, a vinyl monomer and an enzyme, then a catalyst comprising a metallic salt, and irradiating the resulting mixture with ultraviolet light to cause polymerization and form a copolymer of the polysaccharide having enzymatic activity. The metallic salt is preferably a ferric salt and the vinyl monomer is preferably methylacrylate, glycidylmethacrylate, acrylonitride, bis-acyloylpiperazine or symmetrical N, N', N"-trisacryloyl-hexahydrotriazine.

Abstract: Enzymes or enzyme producing microorganisms are immobilized by contacting an aqueous medium containing an enzyme or enzyme producing microorganism with tannin, a long chain, polyamine, cationic flocculating agent and a crosslinking agent and separating the resultant enzymatically active reaction product from the aqueous medium. The reaction product has improved physical strength for use in a column bed reactor. A preferred flocculating agent is a water soluble epihalohydrin/polyamine copolymer.

Abstract: Immobilized enzymatically-active substance is prepared by forming a combination of an enzymatically-active substance and an aqueous polyelectrolyte solution containing a substantial amount of alginate, adding the combination to an aqueous precipitation both containing a source of multivalent ion to form beads of gel containing the enzymatically-active substance, drying the gel beads under controlled conditions to significantly reduce the diameter of the beads and cause hardening of the beads to provide increased mechanical strength, and adding the dried beads to a precipitation both containing a multivalent ion to effect further hardening of the beads. The combination of enzymatically active substance and polyelectrolyte solution may contain an epoxy prepolymer. After further hardening in the polyelectrolyte solution, the beads may be suspended in a buffer solution to dissolve the polyelectrolyte and form porous beads.

Abstract: Biologically active substances such as enzymes are immobilized in the pores of a porous support material by introducing a solution of the biologically active substance into the pores of the support material, treating the active substance in the pores to temporarily retain the active substance in the pores and immobilizing the active substance in the pores by crosslinking. Temporary retention of the active substance in the pores may be carried out by precipitation with a precipitating agent or by freeze-drying.

Abstract: Disclosed are methods of producing glucosone which comprises enzymatically oxidizing glucose with glucose-2-oxidase in a first zone and separating the concomitantly produced hydrogen peroxide from said first zone through a semi-permeable membrane into a second zone, said membrane being permeable only to compounds of a molecular weight of less than about 100.

Abstract: Disclosed are methods of producing glucosone which comprises enzymatically oxidizing glucose with glucose-2-oxidase in a first zone and separating the concomitantly produced hydrogen peroxide from said first zone through a semi-permeable membrane into a second zone wherein an alkene is reacted with said hydrogen peroxide to form oxygenated products of said alkene, said membrane being permeable only to compounds of a molecular weight of less than about 100.

Abstract: A membrane and the method of making the same is disclosed for use with glucose analyzers to detect the level of glucose in liquid mediums such as whole blood. The membrane comprises a thin base wafer of a hydrophobic fluorocarbon material such as polytetrafluoroethylene (TEFLON). The wafer is initially etched by removing surface fluorides to produce a hydrophilic surface and is then contacted with a mixed reagent formed by combining in a volume ratio of about 1:1:1 about 4% paraformaldehyde in water, about 5% bovine serum albumin in water and about 10% glucose oxidase in water. The resultant membrane contains glucose oxidase covalently bonded to the surface of the base wafer.

Abstract: To chemically bind either impure or purified enzymes to polyurethane to produce insolubilized bound enzymes which are still enzymically active and which may be more stable than the original enzyme, and which can be reused without appreciable activity loss and whose physical characteristics can be varied depending on the application for which they are intended.

Abstract: A food processing component such as an enzyme extract is microencapsulated by mixing the food processing component in aqueous medium with an oleaginous material such as milk fat to form a water-in-oil emulsion and then dispersing the water-in-oil emulsion in an aqueous liquid such as milk to form a suspension of oleaginous microcapsules containing the food processing compoent. By forming microcapsules containing a cheese flavor producing enzyme extract in milk and making cheese curd from the milk, accelerated flavor production can be obtained during ripening of the cheese curd.

Abstract: An immobilized enzyme membrane for use at the working face of an electrochemical electrode is prepared which comprises an asymmetrical membrane integrally formed from a skin layer substantially incapable of permeating an enzyme therethrough but capable of permeating a gas and a liquid, and a sponge layer having pores containing an enzyme immobilized therein by crosslinking and which pores intercommunicate with one another throughout the sponge layer and provide sufficient porosity for retaining a necessary amount of the enzyme. The immobilized enzyme membrane contains a large amount of enzyme, has good diffusion and permeability, and has stabilized enzyme activity for a prolonged period of time. Additionally, there is obtained a quick response time and good analytical precision when the immobilized enzyme membrane is used at the working face of an electrode of electrochemical measuring instruments.

Abstract: Electrochemical method for determining the concentration of a carbon source and L-amino acid in a fermentation medium or cultured broth by contacting a microbial electrode consisting of an oxygen-sensitive electrode or a carbon dioxide gas-sensitive electrode combined with fixed microbial cells of a micro-organism capable of assimilating said carbon source or decarboxylating said L-amino acid with a sample solution and sensing electrically the rate of current decrease which is caused by the consumed oxygen in the solution in proportion to the concentration of carbon source; or the electric motive force which is caused by the liberation of carbon dioxide in the sample solution in proportion to the concentration of L-amino acid. Microbial electrodes and systems useful in carrying out the aforementioned method.

Abstract: The concentration of ammonia in an aqueous liquid is determined by contacting a sample of the liquid with dissolved oxygen and with a microbial electrode comprising an oxygen-sensitive electrode, a porous membrane, and nitrifying bacteria confined or immobilised by the membrane which are in direct or close contact with the diaphragm of the electrode. The rate of oxygen consumption under otherwise uniform conditions is as precise a measure of concentration of ammonia as a conventional colorimetric method and distillation-titration method.

Abstract: Compositions and methods featuring, in one aspect, an enzyme assay in which one of a pair of enzymes is immobilized on an insoluble support, and brought into contact with a solution containing the other enzyme of the pair and the substrates of both enzymes. The enzymes catalyze reactions between the substrates, and one or more products of the last such reaction are measured.