Aspartic acid manufacture

Fumaric acid occurs naturally in many plants and is named after Fumaria officinalis, a climbing aimual plant, from which it was first isolated. It is also known as (E)-2-butenedioic acid, aHomaleic acid, boletic acid, Hchenic acid, or /n j -l,2-ethylenedicarboxylic acid. It is used as a food acidulant and as a raw material in the manufacture of unsaturated polyester resins, quick-setting inks, furniture lacquers, paper sizing chemicals, and aspartic acid [56-84-8]. 

Although DTPAMP is a suitable ligand for this reaction as well, the industrial process uses the diphosphine DNNP. Unfortunately, the product is initially obtained in rather modest enantiomeric excess (83%), but recrystallization improves this to 97%. In the manufacture of aspartame, coupling with natural (and therefore 100% ee) aspartic acid turns the 1.5% of the minor enantiomer into a diastereoisomeric impurity that can be removed by crystallization (essentially a resolution). 

A biocatalytic enantioselective addition of ammonia to a C=C bond of an a,)9-unsaturated compound, namely fumaric acid, makes the manufacture of L-aspartic acid possible on an industrial scale. This process, which is applied by, e. g., Kyowa Hakko Kogyo and Tanabe Seiyaku, is based on the use of an aspartate ammonia lyase as a biocatalyst [119]. Another comparable reaction is the asymmetric biocatalytic addition of ammonia to trans-cinnamic acid, which represents a technically feasible process for the production of L-phenyl-alanine [120]. 

M. Terasawa, S. Nara, H. Yamagata, H. Yu-gawa, Manufacture of d-Aspartic Acid and/or L-Malic Acid with Aspartase and Fumarase, Mitsubishi Petrochemical Co., 1991, JP06014787. 

Production of L-aspartic acid from fumaric acid by stereoselective addition of ammonia under the action of the intracelluar aspartase in E. coli (Tanabe Seiyaku Co., Ltd.). When a 1000-liter column is used, theoretical yield of L-aspartic acid is 3.4 tons per day (and even considerably higher for mutant strains and plasmid pNKl01-harboring strains). A similar industrial process using the immobilized E. coli aspartase (instead of the whole cells) was established earlier by Kyowa Hakko Kogyo, Co., Ltd.. L-Aspartate is mainly used as a building block for the manufacture of the sweetener aspartame [170]. 

Polymer additives can improve manufacturing processes and product quality, as they aid the formation of a continuous coating phase without any detrimental effect to the polymer. Biomedical applications of acrylic terpolymer with arginylglycylaspartic acid, i.e., a tripeptide composed of L-arginine, glycine and L-aspartic acid peptides, have been studied by Fussell and Cooper [39]. Chauhan and co-workers have investigated the biological activities of synthesised terpolymers based on p-hydroxybenzaldehyde... 

Acidic and basic amino acids, like glutaric acid, aspartic acid and lysine, are also isolated from protein hydrolysates for artificial nutrition. The fractions are filtered off under sterile conditions and further purified by crystallisation. Since the BSE crisis, the supply with amino acids has come under scrutiny manufacturers had to assure regulators and customers likewise, that their starting material does not originate from cattle. Mostly used are poultry feathers and pork gelatine. [62]... 

Aspartic acid, alanine, phenylalanine, and lysine were manufactured by enzymatic route. Immobilized E. coli cells expressing aspartate or the immobilized enzyme has been used in the commercial production of aspartic acid from ammonia and fumaric acid. Chibata and coworkers also produced alanine by microbial Pseudomonas dacunhae) L-aspartate P-decarboxylase with aspartate as the starting material. Phenyl alanine was manufactured from fw s-cinnamic acid and ammonia by the enzymatic route by phenyl alanine ammonia lyase as catalyst or from phenyl pyruvate and aspartic acid using transaminase. 

Amino acid surfactants (AAS), both natural and synthetic types, have been the subject of many smdies, due mostly to their huge potential application in pharmaceutical, cosmetic, household, and food products. The AAS are derived from acidic, basic, or neutral amino acids. Amino acids such as glutamic acid, glycine, alanine, arginine, aspartic acid, leucine, serine, proline, and protein hydrolysates have been used as starting materials to synthesize AAS commercially and experimentally. Methods of preparation include chemical, enzymatic, and chemoenzymic processes, although chemical processes have been prevalent due to their relatively low cost of production. In recent years, more research papers have focused on the use of enzymatic methods to synthesize AAS. It is our opinion that the enzymatic approach would be more attractive to manufacturers in the near future. 

Aminolysis of the intact rings with taurine leads to the formation of poly(2-sulfoethyl aspartamide) silica and the reaction with ethanolamine to the formation of poly(2-hydroxyethyl aspartamide) silica. Poly(succinimide)-based silica phases are manufactured by PolyLC (Columbia, MD, USA) under the trade names of PolyCAT A for poly(aspartic acid) silica, PolySulfoethyl A for poly(2-sulfoethyl aspartamide) silica, and PolyHydroxyethyl A for poly(2-hydroxyethyl aspartamide) silica. All three poly(succinimide)-based columns have a pore size of 200 A and a surface area of 188 m /g. Various poly(succinimide)-based columns have been used for the separation of carbohydrates, phosphorylated and nonphosphorylated amino acids, petides and glycopeptides, oligonucleotides, and various other polar analytes under HILIC conditions, but lately lost some of their momentum due to a lower chromatographic efficiency in comparison to more modern HILIC phases and column bleed [44]. 

These techniques, in which mutant strains are selected for their ability to overproduce metabolites, represent an important advance in the industrial development of microbial synthesis. Their use to improve amino-acid manufacture was not new they had already been used to improve the titres of antibiotics but the nature of the changes introduced into the metabolism of the mutated organisms could not be interpreted in the way that was possible for amino-acid synthesis. What is, perhaps, also apparent is that the technique of interfering with the metabolic pathway between aspartate and lysine is, in principle, no different from the use of sulphite to inhibit the synthesis of ethanol (section 6.2.1.2). In one case C. glutamicum overproduces lysine, while in the other S. cerevisiae will produce glycerol. 

A low calorie artificial sweetener which was approved for human consumption by the Food and Drug Administration (FDA) in mid-August 1981. It is manufactured by G. D. Searle and Company of Skokie, Illinois, and sold under a different brand name. Chemically, aspartame is the combination of the two amino acids, aspartic acid and phenylalanine—a dipeptide. It is about 180 times sweeter than table sugar. Therefore, it provides the same sweetness as sugar with fewer calories. Furthermore, it does not promote tooth decay, nor does it have an after taste. 

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