Lipid-protein—carbohydrate

MEMBRANES ARE COMPLEX STRUCTURES COMPOSED OF LIPIDS, PROTEINS, CARBOHYDRATES... 

In addition to water and inorganic solids (salts dissolved in cell fluids, shells, and bones), organisms consist of a mix of organic substances. Some of these are macromolecules (e.g., globular proteins, cellulose). Some combine to form subcellular and tissue structures built with combinations of lipids, proteins, carbohydrates, and some specialized polymers like cutin or lignin (Fig. 10.2). These diverse organic materials cause organisms to have diverse macromolecular, cellular, and tissue portions that may be apolar, monopolar, and/or bipolar. 

Organism (reference)a %Lipid %Protein %Carbohydrate Other... 

Phosphorus, in combination with calcium, is important for bone mineralization, as well as for many chemical reactions in the body (NAS 1980A). Like calcium, most of the body s phosphorus (80-90%) is found in bones. The remaining 10 to 20% exists as soluble phosphate in blood, cells, lipids, proteins, carbohydrates, and energy-transfer enzymes (NAS 1980A). 

Lipid-Protein-Carbohydrate Interactions. Evidence for such complex interaction was recently reported by Huang et al (36) who observed that the addition of corn lipids to zein and corn carbohydrates enhanced the formation of alkylpyrazines, indicating that lipid-derived free radicals may accelerate the rate of Maillard reactions. Two of the alkylpyrazines, identified in such mixtures after heating for 30 minutes at 180°C, have 5-carbon alkyl substitution at the pyrazine ring and could only be explained by interaction of lipid or lipid decomposition products. These authors suggested that condensation of amino ketones, formed by protein-carbohydrate interaction, may yield 3,6-dihydropyrazine which would in turn react with pentanal, a lipid oxidation product, to form 2,5-dimethyl-3-pentylpyrazine. 

Many pyrazines were isolated and identified in cooked foods, especially in cooked meats (27). Pyrazines comprised over 40% of the volatile compounds found in cooked pork liver (28). Two pyrazines, 2-methyl-3(or 6)-pentylpyrazine and 2,5-dimethyl-3-pentylpyrazine were among 52 volatiles identified as lipid-protein-carbohydrate interaction products in a zein regular or waxy corn starch-corn oil model system (7). 

This disease is of considerable interest in relation to oxypurine metabolism, although a wide variety of potential metabolic abnormalities have been said to be associated with it. In a review in 1961 Tickner (T4) asserted that there was evidence to support the postulate that psoriasis was associated with alterations in lipid, protein, carbohydrate, and mineral metabolism as well as in serum protein level. Investigators have since supported a myriad of hypotheses. Note has been taken of variations in carbohydrate metabolism (R16), and of changes in the synthesis of hyaluronic acid with resultant alterations in transport mechanisms (CIO). Changes in fatty acid levels and metabolism (C8), alterations of aldolase activity (C6), increased proteolytic activity (S33), and alterations in the composition of proteins in psoriatic scales (L20) have been suggested. Changes in serum copper content in psoriatic patients have been observed (L18). 

Oxygen radicals produce cellular dysfunction by reacting with lipids, proteins, carbohydrates, and DNA to extract electrons (summarized in Fig. 24.7). Evidence of free radical damage has been described in over 100 disease states. In some of these diseases, free radical damage is the primary cause of the disease in others, it enhances complications of the disease. 

The focus of Sawayama and collegues ° was on the hydrothermal treatment of Dunaliella tertiolecta and B. braunii in terms of energy balance sheet and CO2 reduction. They concluded that algae with higher lipid content are better suited for the production of biocrude than micro-algae with low lipid content. These results confirm that the algal feedstock composition (lipids, proteins, carbohydrates) influences the individual compounds identified as well as the biocrude functional group chemistry. ... 

Fourier transform infrared (FTIR) and Raman spectroscopy can provide important structural information on the molecular composition of a sample as well as relative quantification of lipids, proteins, carbohydrates and a variety of phosphorylated biomolecules within cells or tissue. However, sample preparation is the key to realizing the full potential of these technologies. This element of the experimental design can have a significant impact on the interpretation of spectra for their biochemical relevance and on the spatial distribution of biomolecules in imaging studies. 

The presence of lipids, proteins, carbohydrates and other substances significantly influences the retention of aromatic compounds in foods and has an effect on their odour intensity and quality (e.g. the odour threshold values of non-polar substances measured in water are usually lower than the values measured in... 

CH3 asymmetric stretch lipids, proteins, carbohydrates, nucleic acids... 

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