Abstract: Polymers of maleic acid may be prepared by thermally polymerizing malic acid, maleic acid or fumaric acid with less than one equivalent of ammonia. The polymers are modified by the incorporation of amines, carboxylic acids or combinations thereof. The polymers formed are excellent inhibitors of alkaline earth salt deposition, dispersants, tartar control additives, detergent additives, and water treatment agents.

Abstract: Copolymers of polyaspartic acid which are suitable for the inhibition of scale deposition were obtained by reacting maleic acid, an additional polycarboxylic acid and ammonia in a stoichiometric excess, at 120.degree.-350.degree. C., preferably 180.degree.-300.degree. C., to provide copolymers of polysuccinimide. In a second embodiment, a polyamine was added to the reaction mix. These intermediate polysuccinimide copolymers could then be converted to the salts of copolymers of polyaspartic acid by hydrolysis with a hydroxide.Such copolymers are useful in preventing deposition of scale from water and find applications in treating water. Other applications include scale prevention additives for detergents. In addition, such copolymers inhibit dental tartar and plaque formation.

Abstract: Polymers of maleic, fumaric or malic acids or maleic, fumaric or malic acid and ammonia with amino acids are prepared by heating at 180.degree.-350.degree. C., preferably 200.degree.-300.degree. C. The polymer formed may be converted to a salt by hydrolysis with a metal hydroxide or ammonium hydroxide.

Abstract: Polyamino acids or their salts mixed with citric acid or its salts, in a ratio of 75:25 to 0.1:99.9, polyamino acid or its salt to citric acid or its salts, and especially in a ratio of 1:1 to 1:99 polyamino acids or their salts to citric acid or its salts, provide a much higher rate of chelation of calcium ion than expected on the basis of the addition of the polyamino acid to citric acid. Such mixtures may be used in high volume water applications such as boiler, cooling, oil well, agricultural sprays and irrigation water. They are also useful in preventing scale formation on fabrics when formulated with laundry detergents and in preventing scale formation on glassware when formulated in dishwashing detergents.

Abstract: Higher molecular weight copolymers of polyaspartic acid which are suitable for the inhibition of scale deposition may be obtained by reacting maleic acid and ammonia in a stoichiometric excess, with a diamine or a triamine, at 120.degree.-350.degree. C., preferably 180.degree.-300.degree. C., and then converting the copolymer of polysuccinimide formed to a salt of a copolymer of polyaspartic acid by hydrolysis with a hydroxide. Alkyl or substituted alkyl groups may be incorporated in the backbone of the polymer by adding a alkyl or substituted alkyl monoamine to maleic acid and ammonia and heating at 120.degree. C. or more until polymerization has occurred.

Abstract: Copolymers of polyamino acids formed by reaction of polysuccinimide with alkyl, alkenyl, aromatic amines or alkyl and alkenyl polyamines are useful as inhibitors of mineral scale deposition. Such compounds may be used in high volume water applications such as boiler, cooling, oil well, agricultural sprays and irrigation water. They are also useful in preventing scale formation on fabrics when formulated with laundry detergents and in preventing scale formation on glassware when formulated in dishwashing detergents.

Abstract: Solutions of polymers of aspartic acid or its amine copolymers prepared by thermal condensation are reacted with a decolorizing agent selected from the group consisting of hypochlorfte, chlorine, chlorine dioxide, hydrogen peroxide, a peroxycarboxylate or ozone, sufficient in strength to effect the desired decolorization.

Abstract: An oral pharmaceutical composition comprising a hydrophobic resin or ion exchange resin which has a therapeutic agent bound thereto forming an agent-resin complex is disclosed. The complex is coated with a water-permeable diffusion barrier of poly(vinyl alcohol) polymer cryogel.

Abstract: Copolymers of polyamino acids formed by reaction of polysuccinimide with alkyl, alkenyl, aromatic amines or alkyl and alkenyl polyamines are useful as inhibitors of tartar deposition. Such compounds may be used in conventional dentrifice compositions to prevent tartar deposition on natural or false teeth.

Abstract: A controlled-release bandage containing therapeutic agents in a poly(vinyl alcohol) cryogel is disclosed. The bandage may include particulate absorbants such as ion exchange resins and hydrophobic particles to further insure controlled and constant release of therapeutic agents. The bandage may also include plasticizing agents to provide softness in the event of drying the bandage.

Abstract: This invention discloses methods for manufacture and use of poly(ammonium acrylate) and polyacrylamide hydrogels in agricultural applications. Such hydrogels are applied to the soil or the plants by spraying. Spraying is advantageous over other methods of application, such as mixing with soil and broadcasting because of enhanced plant contact, evenness of distribution, and reduced labor. The gels are prepared for spraying by adding water to provide a readily deformable polymer which will pass through a spray apparatus. The hydrogels sprayed may include additives including micronutrients, maconutrients, pesticides, microbes, plant growth regulators, surfactants, and freezing point modifiers. Use of the hydrogels saves irrigation water and ameliorates salting of irrigated cropland. Sprayed hydrogels may also be used to protect crops from freezing and to protect foliage from desiccation.

Abstract: An immobilized isozyme of Lipase MY or AY from Candida rugosa is used for stereoselectively hydrolyzing racemic mixtures of esters of 2-substituted acids, other than 2-halo propionic acids, transesterifying esters or acids or esterify acids or alcohols, at high enantiomeric excess, in an organic solvent. Immobilization of the isozyme may be carried out in the presence of an organic acid such as stearic acid. The immobilized isozyme may be used with a fatty acid or fatty acid ester that increases stereoselectivity or rate of hydrolysis of a mixture of racemic esters.

Abstract: A composition comprising immobilized cells obtained by applying a dispersion of cells and curable prepolymer material selected from the group consisting of polyazetidine prepolymers, carboxymethyl cellulose, polyurethane hydrogel prepolymers and polymethylene isocyanates. as a coating to a solid inert carrier and curing the prepolymer on the carrier at a temperature below the temperature at which enzyme activity of the cells is significantly reduced. The composition may be used to produce various materials such as L-aspartic acid, L-alanine, 6-Aminopenicillanic acid, high fructose corn syrup, prednisolone or phenylalanine.

Abstract: Phenylalanine is produced by contacting cells having transaminase activity with phenylpyruvic acid or phenylpyruvate in the presence of an amine donor. The cells may be ruptured or permeabilized to release their transaminase activity. Preferably, the cells are immobilized with a polyazetidine polymer. Preferred reaction conditions are an excess of amine donor in a ratio of at least 1.1:1 amine donor to phenylpyruvic acid or phenylpyruvate and a pH of 5-10 such as to convert at least 85% of the phenylpyruvic acid or phenylpyruvate to phenylalanine. Phenylalanine may also be produced from cinnamic acid using immobilized cells having phenylalamine ammonia lyase activity.

Abstract: Microbial cells are immobilized with a curable polyaziridine or polyfunctional aziridine prepolymer to obtain an insoluble, crosslinked polymer containing the cells. The microbial cells immobilized may be cells having L-aspartase or L-phenylalanine transaminase activity for the production of L-aspartic acid or L-phenylalanine. The polymer containing the cells may be formed as a coating on a solid inert carrier.

Abstract: A process is disclosed for preparing phenylalanine which comprises contacting phenylpyruvic acid or phenylpyruvate with immobilized whole cells having transaminase activity in the presence of an amine donor. The cells are preferably immobilized with a polyazetidine polymer. Ruptured or permeabilized cells, with the enzyme in the free or immobilized state, may also be used. The preparation of phenylalanine from cinnamic acid using immobilized cells having phenylalanine ammonia lyase activity is also disclosed.

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: L-leucine is prepared by cultivation of an analogue-resistant mutant of Arthrobacter citreus in an aqueous nutrient medium under aerobic conditions. The cultivation is preferably carried out at about 30.degree. C. and at a pH of 5 to 0.8. L-leucine is recovered from the fermentation broth. In a preferred embodiment the mutant is further mutated, and the second mutant is similarly fermented to prepare L-leucine.

Abstract: L-leucine is prepared by cultivation of an analogue-resistant mutant of Brevibacterium thiogenitalis in an aqueous nutrient medium under aerobic conditions. The cultivation is preferably carried out at about 30.degree. C. and at a pH of 5 to 8. L-leucine is recovered from the fermentation broth.

Abstract: L-isoleucine is prepared by cultivation of an analogue-resistant mutant of Brevibacterium thiogenitalis in an aqueous nutrient medium under aerobic conditions in the presence of from 0.001 to 15 w/v percent of a post-threonine precursor for L-isoleucine. The cultivation is preferably carried out at about 30.degree. C. and at a pH of 5 to 9. L-isoleucine is recovered from the fermentation broth.