Amino acids improvements

Y-H Lee, T-I Lin. Capillary electrophoretic determination of amino acids. Improvement by cyclodextrin additives. J Chromatogr A 716 335-346, 1995. 

Kajiwara, K., Okuno, M., Kobayashi, T., Honma, N., Maki, T., Kato, M., Ohnishi, H., Muto, Y., Moriwaki, H. Oral supplementation with branched-chain amino acids improves survival rate of rats with carbon tetrachloride-induced liver cirrhosis. Dig. Dis. Sci. 1998 43 1572-1579... 

Reduced beer losses Reduced losses of bitter substances Reduced risk of contamination Increased utilization of amino acids Improved cooling possibilities Effective automatic cleaning and sanitation Efficient CO2 collection and recovery Prolonged fllhng with subsequent brews (wort) can lead to inhomogeneity of the batch and deterioration of beer quality... 

Ring-opening of aziridinecarboxylic acids has been used in the conversion of threonine into /Areo-3-methylcysteine and in the synthesis of p-alkoxy-a-amino-acids. Improved methods have appeared for the synthesis of iV-(phosphono-acetyl)-amino-acids and for the preparation of y-esters of glutamic acid and (3-esters of aspartic acid. The protected P-hydroxy-a-amino-acids (278) are converted into a-fluoro-P-amino-acids (279) with DAST (Scheme 137). ... 

We therefore use smooth density estimation techniques that are more reliable than the histogram estimates. To improve the reliability for rare amino acid pairs, we use clustering techniques that identify similar pairs that can be modeled by the same density. 

Citric acid is used in carbonated beverages to provide tartness, modify and enhance flavors, and chelate trace metals. It is often added to jams and jellies to control pH and provide tartness. It is used in cured and freeze-dried meat products to protect the amino acids (qv) and improve water retention. Bakers use it to improve the flavor of fmit fillings in baked goods. Because citric acid is a good chelator for trace metals, it is used as an antioxidant synergist in fats and oils, and as a preservative in frozen fish and shellfish (7) (see Antioxidaisits). 

The nutritional value of a proteia can be improved by the addition of amino acids of low abundance ia that proteia. Thus the fortification of plant proteias such as wheat, com, and soybean with L-lysiae, DL-methionine, or other essential amino acids (L-tryptophan and L-threonine) is expected to alleviate some food problems (11). Such fortification has been widespread ia the feedstuff of domestic animals. 

After World War II, analytical methods for amino acids were improved and new methods were iatroduced. The first was microbial assay usiag lactic acid bacteria which require all of the regular amino acids for growth. Manometric determiaation (by use of a Warburg manometer) of CO2 Hberated by the... 

Synthesis of Peptide. There is continual progress ia the improvement of instmments and reagents for peptide synthesis, especially "soHd phase polymerization" (90) (see Proteins). This method is suitable for the synthesis of peptides with 20 30 amino acid units. 

Refs. 21, 22, 155. Abbreviations AHV, a-amino-(3-hydroxyvaleric acid Horn, L-homoserine AEG, (3 -(2-aminoethyl)-L-cysteine ppc, phosphoenolpymvate carboxylase the strain improvement largely depends on the transduction technology sensitive resistant —, auxotroph or deficient , leaky auxotroph +, prototrophic revertant. Table 7. Amino Acid Production from Hydrocarbons ... 

Currently available proteins are all deficient to greater or lesser extent in one or more of the essential amino acids. The recently advanced plastein reaction (229) has made it possible to use protein itself as substrate and to attach amino acid esters to the protein with high efficiency. By this method, soy bean protein (which is deficient in methionine) has been improved to the extent of having covalently attached L-methionine at 11%. 

Pea.nuts, The proteins of peanuts are low in lysine, threonine, cystine plus methionine, and tryptophan when compared to the amino acid requirements for children but meet the requirements for adults (see Table 3). Peanut flour can be used to increase the nutritive value of cereals such as cornmeal but further improvement is noted by the addition of lysine (71). The trypsin inhibitor content of raw peanuts is about one-fifth that of raw soybeans, but this concentration is sufficient to cause hypertrophy (enlargement) of the pancreas in rats. The inhibitors of peanuts are largely inactivated by moist heat treatment (48). As for cottonseed, peanuts are prone to contamination by aflatoxin. FDA regulations limit aflatoxin levels of peanuts and meals to 100 ppb for breeding beef catde, breeding swine, or poultry 200 ppb for finishing swine 300 ppb for finishing beef catde 20 ppb for immature animals and dairy animals and 20 ppb for humans. 

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