Asparagine supplemental

After a certain time period asparagine supplementation was stopped (day 0), as a consequence of which asparagine became exhausted from the culture medium and the production of factor VIII dropped (days 1-4). Asparagine (200 xmol) was later added to the medium (day 4), the result of which was an increase in the levels of factor VIII. 

Marquezi ME, Roschel ElA, dos Santa Costa A, Sawada EA, Eancha AEl Jr. Effect of aspartate and asparagine supplementation on fatigue determinants in intense exercise. Int J Sport Nutr Exerc Metab. 2003 13 65-75. 

Spectra of many of the common amino acids not yet discussed are shown in Fig. 2, kindly made available by Sussman and Gratzer (1962). The data of this figure are usefully supplemented by the earlier but less extensive (2000-2300 A) observations of Saidel et al. (1952). In addition to some duplication of the amino acids of Fig. 2, Saidel et al. showed spectra of cysteic acid, hydroxyproline, asparagine, valine, isoleucine, and glycine. The monoamino, monocarboxylic amino acids, including the hydroxyamino acids and the imino acids, are seen to have very similar spectra at wave-... 

The nutritional requirements for a certain metabolite, however, may also be influenced by the cell population density. For example, serine, cystine, glutamine and asparagine have been shown to be required at low, but not at high, cell densities (Eagle Piez, 1962). This occurs in situations when the newly synthesized metabolite is lost into the medium in amounts that exceed the biosynthetic capacity of the cell. The critical population density can be regarded as that which is able to condition the medium, i.e. to build up a concentration in equilibrium with the minimum effective intracellular level, before the cells die of the specific deficiency. At high cell densities, however, the cell culture medium can require supplementation with extra amino acids, in order to prevent their depletion. 

The flow rate was maintained at one reactor volume per day. Samples were taken daily for cell counts, factor VIII analysis and amino acid analysis. At the start of the production phase the medium was supplemented with 200 xmol of asparagine (50 jxmol of asparagine was present in the unsupplemented medium). 

Supplementation of the raw substrate may be required in order to stimulate growth, induce enzyme synthesis, or prolong secondary metabolite production. Most traditional food fermentations do not require nutritional supplementation. In cellulosic media, supplements of 0.5% of glucose or cellobiose, 0.5% peptone, asparagine, or yeast extract are in use [75]. 

For most Claviceps strains synthetic media can be used. In industry sucrose or sorbitol is used (seldom other C-sources) in concentrations of 70-250 g/1. As a secondary C-source usually citrate in concentration of 5-10 g/1 is used. NH4 salts, asparagine or NOf salts serve as N-source and phosphate—vide supra—and other inorganic salts are supplemented. Inoculation medium differs from the production medium by higher phosphate concentration—up to 10 mM, different N-source, some additional vitamins (biotin, aneurine) and by complex nutrients added— yeast extract, corn steep, malt extract etc. 

Lancha AH Jr, Recco MB, Abdalla DS, Curi R. Effect of aspartate, asparagine, and carnitine supplementation in the diet on metabolism of skeletal muscle during a moderate exercise. Physiol Behav 1995 57 367-371. 

The claim that asparagine or aspartic acid supplementation improves endurance has not been confirmed in human studies. Asparaginase, which degrades asparagine, is widely used in the treatment of pediatric leukemia since the resulting asparagine depletion leads to apoptosis of leukemic cells. 

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