Amino acids fermentation

Among the vitally necessary elements the most important are Fe, Zn, K, Ca, S. Some of them are imbedded in the stmcture of many ferments, amino acids, intracellular liquid, the other define transmembrane electrical potential. In the paper the contents of elements in whole blood and semm by X-ray fluorescence spectrometry is studied. 

All amino acids, except proline, may be used by Saccharomyces cerevisiae in grape juice fermentation. Amino acids can be directly used to synthesize proteins. However, the amino acid composition of the grape juice is not necessarily similar to the needs of the cell. For that reason, yeasts must use the remaining amino acids to synthesize those which it lacks (Hensche and Jiranek 1993 Ribereau-Gayon et al. 2000b). In this case, ammonia is incorporated into other amino acids whereas the carbon skeleton is metabolized by the cell. 

Chemicals. Numerous chemicals, such as amino acids, polymers, organic acids (citric, acetic, and lactic), and bioinsecticides are produced by industrial fermentation. Amino acids are used as a food and animal feed, as well as in the pharmaceutical, cosmetic, and chemical industries. Bacteria such as Micrococcus luteus and Corynebacterium utamicum are used for industrial fermentation to produce chemicals. Bacterial toxins are effective against different insects. Since the 1960 s, preparations of the bacteria Bacillus thuringiensis have been produced by fermentation as a biological insecticide. 

Found in high numbers (0-66%) in gingival plaque and periodontal pockets. Proteolytic organisms fermenting amino acids to formate, acetate and succinate. May produce collagenase, hyaluronidase and chondroitin sulphatase. Probable periodontal pathogens. 

Strictly anaerobic, common in plaque and associated with adult periodontitis. Ferment amino acids. 

First appearance in early teens and associated with periodontal disease. Anaerobic metabolism obtaining essential nutrients from the blood and gingival fluid, e.g. putrescine, spermine and isobutyrate. Also ferment amino acids to acetate, ammonia, hydrogen sulphide and carbon dioxide. Invade tissues and are highly pathogenic. Represent 2% of total organisms in healthy tissues and about 40% in periodontal disease. 

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. 

Modern methods of amino-acid and peptide analysis, have enabled the complete amino-acid sequence of a number of proteins to be worked out. The grosser structure can be determined by X-ray diffraction procedures. Proteins have molecular weights ranging from about 6 000 000 to 5 000 (although the dividing line between a protein and a peptide is ill defined). Edible proteins can be produced from petroleum and nutrients under fermentation. 

H. Wood, H. L. Drake, and S. Hu iu E. E. SneU, ed.. Some Historical and Modem Aspects of Amino Acid, Fermentations, andNucleic Acids, (symposium ... 

Because of the simplicity of swiae and poultry feeds, most feed manufacturers add vitamins (qv) and trace minerals to ensure an adequate supply of essential nutrients. Amino acids (qv) such as methionine [7005-18-7] lysiae [56-87-17, threonine [36676-50-3] and tryptophan [6912-86-3], produced by chemical synthesis or by fermentation (qv), are used to fortify swiae and poultry diets. The use of these supplements to provide the essential amino acids permits diets with lower total cmde proteia coateat. 

Other L-amino acids are manufactured much more economically ia thousands of tons per year ia Japan by simplified fermentations direcdy from glucose, ethanol, acetic acid, glycerol, or / -paraffin, by means of selected auxotrophic, regulatory, and analogue-resistant bacterial mutants (94,95). 

In the 1950s, a group of coryneform bacteria which accumulate a large amount of L-glutamic acid in the culture medium were isolated (21). The use of mutant derivatives of these bacteria offered a new fermentation process for the production of many other kinds of amino acids (22). The amino acids which are produced by this method are mostiy of the T.-form, and the desired amino acid is singly accumulated. Therefore, it is very easy to isolate it from the culture broth. Rapid development of fermentative production and en2ymatic production have contributed to the lower costs of many protein amino acids and to their availabiUty in many fields as economical raw materials. 

Fig. 5. Fermentative production of amino acids (140). A, pure culture B, inoculation C, boiler D, air compressor E, air filter F, seed tank G, ammonia water for pH control H, fermenter I, sterilizer , culture media K, preparation tank L, centrifugal separator M, ion-exchange column N, crystallizing...

Table 6. Fermentative Production of Amino Acids and Their Related Substances from Carbohydrates ...

Further efficient fermentative methods for manufacture of riboflavin have been patented one is culturing C. famata by restricting the carbon source uptake rate, thereby restricting growth in a linear manner by restriction of a micronutrient. By this method, productivity was increased to >0.17 g riboflavin/L/h (63). The other method, using Bacillus subtilis AJ 12644 low in guanosine monophosphate hydrolase activity, yielded cmde riboflavin 0.9 g/ L/3 days, when cultured in a medium including soy protein, salts, and amino acids (64). 

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