Fatty acid chain length, alteration

The effect of altering the fatty-acid chain length of sodium salts of linear fatty acids on the air entrained in mortars is illustrated in Fig. 3.9 [5], The superiority of the 9-11 carbon chain length fatty-acids is clearly shown and, in practice, fatty-acid fractions with a high Cjq content are chosen the C9 and fatty acids do not occur... 

A. Altering the fatty acid chain length and level of ... 

The permeability of liposomes prepared from synthetic lecithin have provided useful data which help to explain functional changes in membranes in terms of an alteration in bilayer structure. For example, the rate of water permeation through liposomes decreases 10-fold, and the of permeation increases from about 9 to 26 kcal mol" below the transition temperature for the lipids (Block et al., 1975). Rates of permeation for electrolytes and nonelectrolytes were found to be maximum at, or near, the temperature of the transition where fluid- and solid-phase lipids coexist, and decreased in both the gel and fluid phases below and above this temperature (Block et al., 1976). Since the order-disorder transition of lipids is accompanied by a decrease in the area per molecule, it was postulated that pores developed in the bilayer at the transition temperature and that the number and lifetime of these pores was dependent upon the fatty acid chain length of the lipids (Block eta/., 1976). 

APPROACHES TO THE DESIGN OF ACYL-ACP DESATURASES WITH ALTERED FATTY ACID CHAIN-LENGTH AND DOUBLE BOND POSITIONAL SPECIFICITIES... 

Approaches to the Design of Acyl-ACP Desaturases with Altered Fatty Acid Chain Length and Double Bond Positional Specificities. 

MEMBRANE FLUIDITY is regulated by altering the chain length of fatty acids, the presence of m-unsaturations, and the content of cholesterol. 

Derivatives of UP. Much recent work has involved interpreting substituent effects on the solid-state reactions of UP, and more than 60 derivatives have been prepared for this purpose. Some substitutions drastically alter the packing pattern within crystal layers, which makes their influence difficult to interpret. This is particularly true when the parity of the carbon chain length of the constituent fatty acids is changed from odd to even. In the discussion below we focus on the following substitutions of UP which give the same layer structure and are thus easier to understand ... 

Metabolically altered fatty acids (i.e., fatty acids that have been reduced in chain length by ot- and/or p-oxidation and have undergone various processes of oxidation or reduction) occur in many essential oils. Many of these intermediary metabolites are converted ultimately to esters, acids, alcohols, aldehydes, alkenes, and alkanes (Fig. 2.22). These fatty acid derivatives are relatively volatile and occur widely as components of the essences of flowers, fruits, stems, leaves. 

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