Lipids energy sources

Intravenous lipid emulsions are used as an energy source in PN and to prevent or treat essential fatty acid deficiency. 

Marine lipids are important biological energy sources and have been used as tracers in food studies [395-398]. Some lipids, however, are pollutants [399, 400], and all lipids can potentially act as solvents, transporters, or sinks for pollutants [374,399,401,402]. 

German, J. B., and Dillard, C. J. (2006). Composition, structure and absorption of milk lipids A source of energy, fat-soluble nutrients and bioactive molecules. Crit. Rev. Food Sci. Nutr. 46, 57-92. 

Carbohydrates are relevant in medicinal chemistry. The outdated notion that carbohydrates serve only as energy sources in animals and structural materials in plants is no longer tenable. Complex carbohydrates are biochemically important. Carbohydrates, when joined via glycosidic linkages to either proteins or lipids (to produce glycoproteins or... 

The nature and concentration of carbon and nitrogen substrates in the culture medium affect both the energy status and metabolism of the cells. Medium generally contains both a carbohydrate (normally glucose) and a range of amino acids to satisfy the cellular growth requirements (Butler, 2004). Lipids are also important, not only as an energy source, but also as precursors for the synthesis of the cellular membrane components. 

Essential amino acids are those not synthesized by the organism and are required by animal cells in culture. These include specific amino acids such as cysteine and tyrosine but the requirement varies between cell lines. Amino acids are necessary for protein, nucleotide, and lipid synthesis and, in addition, may be used as an energy source. 

Several carrier systems have been shown to be present in the brain endothelium, allowing for the selective transport of a group of common substrates (Table 13.1). The most common system is the one that mediates the transport of glucose, which provides the brain with virtually all its energy. Carrier-mediated mechanisms are also responsible for the absorption of two other energy sources ketone bodies, which are derived from lipids, and lactic acid, a by-product of sugar metabolism. Carrier-mediated transport systems are also involved in the uptake of amino acids by the brain. The brain can manufacture its own small neutral and acidic amino acids however, large neutral and basic amino acids are obtained from the bloodstream. 

Edible oils and fats come under the biochemical classification of lipids owing to their insolubility in water. They are composed of two chemically bonded components, a fatty acid and glycerol there are many different fatty acids. When fats and oils are digested in the body, the fatty acids are liberated. Fatty acids are vital in the diet to act as starting materials for cell structures, for other important bodily chemicals including hormones and as an energy source. 

After training, which increases the oxidative capacity of the muscles, lipid fuels become the major energy source of the working muscles during prolonged exertion sparing carbohydrate utilization. 

Before we consider the specifics of memhrane-protein function, we will consider some general principles of membrane transport. Two factors determine whether a molecule will cross a membrane (1) the permeability of the molecule in a lipid hilayer and (2) the availability of an energy source. 

Lipids (fatty acids, glycerol lipids, and cholesterol) are vital nutrients that serve as an energy source, structural components of the living organisms, and essential to... 

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