Amino acids selected foods

Methylquinoxaline 4-oxide (264) selectively from 2-methylquinoxaline 1,4-dioxide (265) (ascorbic acid, H2O, 90°C, 5 h 58% homologs likewise) the natural amino acids in foods can also reduce such quinoxaline N-... 

The thermal interaction between 2,4-decadienal and cysteine was selected as a model for lipid-protein interaction. 2,4-Decadienal is the major degradation product of linoleic acid and cysteine is a sulfur-containing amino acid in foods. Some heterocyclic compounds identified in the reaction mixture of 2,4-decadienal and cysteine are listed in Table I. 

Inductively Coupled Plasma. Carbohydrates Sugars -Spectrophotometric Methods Starch. Food and Nutritional Analysis Oven/iew Antioxidants and Presen/atives Oils and Fats. Ion-Selective Electrodes Food Applications. Liquid Chromatography Amino Acids. Proteins Foods. Quality Assurance Quality Control. Sampling Theory. Vitamins Fat-Soluble Water-Soluble. Water Determination. 

Warthesen, J. J., R. A. Scanlan, D. D. Bills, and I. M. Libbey. 1975. Formation of heterocyclic n-nitrosamines from reaction of nitrite and selected primary diamines and amino-acids./. Agric. Food Chem. 23 898-902. 

Potentiometric enzyme-based electrodes have found application in clinical, pharmaceutical, food and biochemical analyses to enable the selective determination of a wide range of important enzyme substrates, including amino acids, esters, amides, acylcholines, /Mactam antibiotics, sugars, enantioselective drugs and many others [74]. 

Protein contents of selected oilseeds and legume seeds, and food protein ingredients prepared by various procedures, are shown in Table I. Amino acid contents and protein efficiency ratios (PER s)... 

Various important LC methods for amino acid, peptide and protein analysis were reviewed and evaluated126,127. A review of HPLC methods for the analysis of selected biogenic amines in foods appeared, including methods for extraction and for elimination of interfering compounds128. 

Proteins are nature s polyamide condensation polymers. A protein is formed by polymerization of o-artiino acids, with the amino group on the carbon atom next to the carboxylic acid. Biologists call the bond formed a peptide rather than an amide. In the food chain these amino acids are continuously hydrolyzed and polymerized back into polymers, which the host can use in its tissues. These polymerization and depolymerization reactions in biological systems are all controlled by enzyme catalysts that produce extreme selectivity to the desired proteins. 

A number of criteria could be apphed to organize this chapter, depending on the point of view by which foods are considered. In this chapter, application of HPLC to food analysis will be described considering homogeneous classes of food components lipids, carbohydrates and related substances, proteins, peptides, amino acids, biogenic amines, phenolics, vitamins, and some selected contaminants. 

Animals acquire many of their nutrients in a ready made form from the food that they eat. Plants, however, have to biosynthesise everything that they need for efficient growth. The first section of this chapter discussed photosynthesis, a fundamental biosynthetic process, but plants also synthesise other components that animals do not. These biosynthetic processes are good examples of potentially plant selective herbicidal targets. Amino acids are the building blocks of proteins and as such their biosynthesis is one such process. 

Bioavailability can be influenced directly or indirectly by many physiological, pathological, chemical, nutritional, and processing conditions. Discussion in this chapter will be limited to unit food processing effects upon the bioavailability of nutrients from plant protein foods. The bioavailability of amino acids, carbohydrates, lipids, vitamins and minerals from processed foods will be selectively reviewed. Amino Acids... 

Barbeau, W. E. and Hilu, K. W. (1993). Protein, calcium, iron and amino acid content of selected wild and domesticated cultivars of finger millet. Plant Foods Hum. Nutr. 43,97-104. 

Brcum L, Moller SE, Andersen T, Astrup A. Long-term effect of dexfenfluramine on amino acid profiles and food selection in obese patients during weight loss. Int J Obes Relat Metab Disord 1996 20 147-153. 

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