Effect on amino acid

Amino acid neurotransmitter Constituents of hypericum also appear to have effects on amino acid neurotransmission, particularly GABA. Hypericin and a crude extract bind to GABAA and GABAB receptors (Cott 1997). Hyperforin also inhibits synaptosomal GABA reuptake in the low micromolar range (IC50 values of 0.05-0.10 ug/ml). Activity at GABAA benzodiazepine receptors was noted in extracts of four hy-... 

Millard, P. (1986). The nitrogen content of potato (Solanum tuberosum L.) tubers in relation to nitrogen application -the effect on amino acid composition and yields. Journal of the Science of Food and Agriculture, 37,107-114. 

Maillard (2 ) then used sugars instead of glycerol to investigate the formation of polypeptides by the reaction of amino acids with alcohols. It was found that the aldehyde group (of an aldose) had more intense effect on amino acids than did the hydroxyl groups. This led to the discovery of this reaction. 

The effects of premelanoidins on nitrogen retention is explained by a reduction in protein digestibility due to (a) the inactivation of the proteolytic enzymes, (b) the formation of indigestible peptides (20,38), (c) the inhibitory effects on amino acid absorption (33) and (d) by a decrease in the efficiency of the protein synthesis. The Maillard products also have an inhibitory effect on the intestine saccharidases (39). 

Hemandez-Orte, P., Ibarz, M.J., Cacho, J., Ferreira, V. (2006) Addition of amino acids to grape juice of the Merlot variety Effect on amino acid uptake and aroma generation during alcoholic fermentation. Food Chem., 98, 300-310. 

The expelled CSB meal had a TMEj, value of 3265 kcal/kg DM. They also reported that amino acid digestibility of CSB extruded at 138°C or 154°C did not differ from that of extmded KFSB. Expelling of CSB had no significant effect on amino acid digestibility values when compared with extruding alone. 

Nutrition (includes effects on amino acids, essential fatty acids, vitamins, micronutrients)... 

Monteiro, F.F. and Bisson, L.F. 1992a. Nitrogen supplementation of grape juice. I. Effect on amino acid utilization during fermentation. Am. J. Enol. Vitic. 43,1-10. 

Trombley PQ, Horning MS, Blakemore LJ. 1998. Carnosine modulates zinc and copper effects on amino acid receptors and synaptic transmission. Neuroreport 9 3503-3507. 

De Cespedes, C., Christensen, H. N. Biochim. Biophys. Acta. 3.39 (1), 139 (1974). Complexity in valinomycin effects on amino acid transport... 

Elmore, C.D. and Polles, S.G., Nitrogen fertilization effects on amino acid composition of pecan Carya illinoensis) nutmeats, J. Agric. Food Chem., 28, 902-904, 1980. 

Hydroxycorticosterone, cortisone and, IX, 269 diabetogenic action, 201 effect on >-amino acid oxidase, X, 366, 358... 

It was suggested that the apparent inhibition of brain protein syn thesis by morphine is due to its effect on amino acid transport. 

A similar situation has recently been reported for diabetic man . While a two to threefold Increase of several ketogenic amino acids was found to occur in the plasma of ketoacidotic diabetic patients, a 25-40 percent reduction in the levels of glucogenic amino acids was observed. The mechanisms by which insulin stimulates protein synthesis and reduces amino acid mobilization are poorly understood. It is possible that a fundamental action of insulin on protein metabolism may be the induction of a "translation factor" which in turn allows for polysome formation . It is still not clear, however, to what extent an insulin effect at the cell membrane or an insulin effect on amino acid flux across the cell is necessary for observed effects at the nucleic acid level . ... 

Effect on Amino Acids and Protein Synthesis. The administration of growth hormone induces a positive nitrogen balance, which means that less nitrogen is excreted in the urine and the concentration of amino acid nitrogen in the blood is reduced. 

Studies of the incorporation of labeled amino acid and labeled amino acid precursors (Krebs cycle intermediate or bicarbonate) in diaphragm have dissociated the effect of cortisone on amino acid penetration from its effect on amino acid incorporation and protein synthesis. The results demonstrated that adrenalectomy is without effect on the amino acid uptake by isolated diaphragm. In contrast, corticosteroids inhibit amino acid uptake by the isolated diaphragm. Adrenalectomy enhances and cortisone depresses the incorporation of " C-labeled amino acid, glucose, bicarbonate, and dicarboxylic acid into protein of the diaphragm. It has also been found that corticosteroids decrease amino acid incorporation into proteins in... 

The chemical and enzymatic browning reactions of plant polyphenols and their effects on amino acids and proteins are reviewed. A model system of casein and oxidizing caffeic acid has been studied in more detail. The effects of pH, time, caffeic acid level and the presence or not of tyrosinase on the decrease of FDNB-reactive lysine are described. The chemical loss of lysine, methionine and tryptophan and the change in the bioavailability of these amino acids to rats has been evaluated in two systems pH 7.0 with tyrosinase and pH 10.0 without tyrosinase. At pH 10.0, reactive lysine was more reduced. At pH 7.0 plus tyrosinase methionine was more extensively oxidized to its sulphoxide. Tryptophan was not chemically reduced under either condition. At pH 10.0 there was a decrease in the protein digestibility which was responsible for a corresponding reduction in tryptophan availability and partly responsible for lower methionine availability. Metabolic transit of casein labelled with tritiated lysine treated under the same conditions indicated that the lower lysine availability in rats was due to a lower digestibility of the lysine-caffeoquinone complexes. 

Chloramphenicol has been reported to have no effect on amino acid activation or incorporation of amino acids into sRNA. In high concentration, however, it inhibits nearly completely the incorporation of labelled amino acid into the protein of calf thymus nuclei . The antibiotic thus appears to interfere at a late stage in the process of protein synthesis. It is of interest that its L-erythro isomer has bttle effect on protein synthesis but inhibits the synthesis of a D-glutamyl pol5q>eptide by Bacillus suhtilis. ... 

Hydrogen bonding, effect on amino acid acidity value 223... 

Acid-released sycamore maple cell-wall fragments inhibit cellular growth. High fragment concentrations killed the cultured cells (50). At sublethal doses, wall fragments inhibited the transmembrane movement of amino acids within 1 minute after treatment. After 1 hour of treatment, amino acid transport was restored. Total protein synthesis was suppressed independently of the effect on amino acid transport. Results were related to the mechanism of killing plant cells by pectic enzymes and to the defense responses shown by plants to pathogens. 

There is considerable basis for linking pyridoxine to amino acid metabolism, and the participation of this vitamin in antibody production may be related to such a function. However, in a recent review, Beaton et al. (1954) suggest that pyridoxine is not essential for protein synthesis or maintenance in the rat and that its effect on amino acid metabolism is of a secondary nature. A role for pantothenic acid in protein synthesis has not yet been demonstrated. A relationship between pantothenic acid and peptide bond formation is suggested by the observation of Chantrenne (1944) that coenzyme A, the coenzyme derivative of pantothenic acid, is... 

Fenugreek extract in the continuous culture systan showed no effect on large peptides, small peptides and amino acids prodnctions in the rumen (Busquet et al. 2005) while Yucca extract increased the avaage peptide N concentration by 26.2% but no effect on amino acid concentration and ammonia was found (Cardozo et al. 2004). 

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