Lysine manufacture

Continuous ion-exchange separation technology, which adopts counter-current processing in a rotating turntable, is currently making an impact and 70% of the world s lysine manufacture units use this technology. 

Ajinomoto and BASF are leading lysine manufacturers. For instance, Ajinomoto is expected to expand its global lysine capacity to 300,000 metric tons by 2005 (http //static.highbeam.eom/c/chemicalweek/january262000/ ajinomotoraiseslysineproductionworldwide/). 

H2N-CH2 [CH2j3.CH(NH2) COOH. Colourless needles, m.p. 224 C (decomp.), very soluble in water, insoluble in alcohol. L-(-H)-Lysine is one of the basic amino-acids occurring in particularly large quantities in the protamine and histone classes of proteins. It is an essential amino-acid, which cannot be synthesized by the body and must be present in the food for proper growth. It can be manufactured by various fermentation processes or by synthesis. 

Toray (1) A large Japanese chemicals manufacturer, perhaps best known for its process for synthesizing /-lysine for use as a dietary supplement. The starting material is cyclohexene which is converted in five steps to racemic lysine. An enzymic process isolates the desired optical isomer, the other is recycled. 

Ascorbic acid or vitamin C is found in fruits, especially citrus fruits, and in fresh vegetables. Man is one of the few mammals unable to manufacture vitamin C in the liver. It is essential for the formation of collagen as it is a cofactor for the conversion of proline and lysine residues to hydroxyproline and hydroxylysine. It is also a cofactor for carnitine synthesis, for the conversion of folic acid to folinic acid and for the hydroxylation of dopamine to form norepinephrine. Being a lactone with two hydroxyl groups which can be oxidized to two keto groups forming dehydroascorbic acid, ascorbic acid is also an anti-oxidant. By reducing ferric iron to the ferrous state in the stomach, ascorbic acid promotes iron absorption. 

Caprolactam is used primarily in the manufacture of synthetic fibres and resins (especially nylon 6), bristles, film, coatings synthetic leather, plasticizers and paint vehicles as a cross-linking agent for polyurethanes and in the synthesis of the amino acid lysine (Lewis, 1993). 

There are 22 different AAs in the body of the bird, 10 of which are essential AA (EAA arginine, methionine, histidine, phenylalanine, isoleucine, leucine, lysine, threonine, tryptophan and valine), i.e. cannot be manufactured by the body and must be derived from the diet. Cystine and tyrosine are semi-essential in that they can be synthesized from methionine and phenyla-... 

Near infra red reflectance spectroscopy (NIRS) is becoming increasingly used for the analysis of nutrients in feedstuffs. It is very rapid and cost-effective and may eventually replace the slower chemical methods of analysis used currently in the feed-manufacturing industry. NIRS may also be used for amino acid analysis. Another method now being adopted widely in feed manufacture is to use predichon equations based on chemical or NIRS analysis to predict amino acid contents of some feedstuffs. The NRC (1994) published equations for the predichon of lysine, tryptophan, threonine,... 

Fermentation is also the basis for the manufacture of biomass foodstuffs (primarily protein for animal and human consumption), amino acids (especially monosodium glutamate and L-lysine), and the major industrial feedstock and gasoline additive, ethanol. 

Table 2.1 Lysine damage in good manufacturing practice7,31...

Amino Acids. Amino acids are produced by both fermentation and biocatalysis for use in animal feed, fertilizer, as flavor enhancers, dietary supplements, and in pharmaceutical manufacture. By volume, the most important products are L-lysine, L-methionine, L-threonine, and L-tryptophan, most of which are produced by fermentation. Biocatalysis still plays an important role in amino acid supply and has been used to synthesize both L- and D-amino acids, including a variety of nonnatural analogues. The major producers are Degussa, Tanabe Seiyaku, and Kyowa Hakko. 

De novo fermentation has long been the method of choice for the manufacture of many natural L-amino acids, such as glutamic acid and lysine, and hydroxy acids such as lactic and citric acids. More recently, de novo fermentation is displacing existing multistep chemical syntheses, for example in the manufacture of vitamin B2 (riboflavin) and vitamin C. Other recent successes of white... 

The reactions of proteins in alkaline solution are very important from a number of standpoints. We have already discussed several uses of alkali treatment in food processing in the introduction. When contact between the food and alkali is kept to a minimum at the lowest temperature possible with adequate control of mixing, etc. there is presently no apparent reason to discontinue its use. Low levels of lysinoalanine occur in food which has been processed in the absence of added alkali, even at pH 6 and in the dry state (20). For example, the egg white of an egg boiled three minutes contained 140 ppm of lysinoalanine while dried egg white powder contained from 160 to 1820 ppm of lysinoalanine depending on the manufacturer (20). No lysinoalanine was found in fresh egg white, 3 Elimination and addition of lysine to the double bond of dehydroalanine reduce the level of the essential amino acid lysine. This can be prevented by adding other nucleophiles such as cysteine to the reaction. Whether lysinoalanine (and other compounds formed by addition reactions) is toxic at low levels in humans is not known. 

Carbodiimides are widely used to mediate the attachment of biomarkers to polypeptides. Examples include carbodiimides with ferrocenyl substituents. Also, peptides are covalently modified with ferrocenecarboxylic acid using EDCCl and N-hydroxy-succinimide to promote the coupling to surface lysines. They also mediate the attachment of substituents to single walled nanotubes (SWNTs) and multiwalled nanotubes (MWNTs). Also, microdots are attached to virus molecules using a water soluble carbodiimide. The attachment of viral DNA to gold particles is used in the manufacture of a new type of vaccine. 

An example of this approach is Archer Daniels Midland, which reduced total production costs by over 60 percent by replacing traditional chemical synthesis with an advanced biological fermentation process for the manufacture of L-lysine. 

Although all of the amino acids listed in Table SO-1 are present in the proteins of the human body, not all of them need to be in the food. Experiments have been carried out which show that nine of the amino acids are essential to man. 1 hese nine essential amino acids are histidine, lysine, tryptophan, phenylalanine, leucine, isoleucine, threonine, methionine, and valine. The human body seems to be able to manufacture the others, which are called the non-essential amino acids. Some organisms that we usually consider to be simpler than man have greater powers than the human organism, in that they are able to manufacture all of the amino acids from inorganic constituents. The red bread mold, Neurospora, has this power. 

Nearly 80% of the soybean meal consumed in the United States is fed to nonruminants. Soybean meal is the most economic high-quahty protein available to feed manufacturers hence it assumes a dominant role (3, 4). Cereal-based rations for pigs and poultry may contain soybean meal as the only protein supplement, as a previous requirement for the inclusion of some animal or marine origin protein has been supplanted by the addition of lysine, methionine, and vitamin B12, where economics dictate (5). 

Safflower is a minor oilseed crop limited in production by environmental constraints and by the plant s spiny nature. Unless the seed is well dehulled, the oilcake resulting from oil extraction will have a high fiber content. Undecorticated oil cake has a protein content of 20-22% and an end use as manure. In contrast, removal of the hull improves the protein content to 40%, making it acceptable as cattle feed despite low lysine levels. Leftover hulls and husks are added to cattle feed or are used to manufacture cellulose, insulation, and abrasives (5, 49). 

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