However, not all oils are unsaturated - tropical oils like palm oil and coconut oil are liquid at room temperature yet high in saturated fat. Olive oil and canola oil are also rich in monounsaturated fats. Most vegetable and fish oils contain high quantities of polyunsaturated fats. This choice is easy enough to make because unsaturated fats tend to be liquid at room temperature (for example, olive oil) whereas saturated fats tend to be solid at room temperature (for example, butter).
If you decide to limit or redirect your intake of fat products, then choosing unsaturated fat is more beneficial than choosing a saturated fat. Knowing the connection between chain length, degree of saturation, and the shape of the fatty acid is important for making food choices. These findings appear to be of considerable interest because, according to current views, key processes in lipid-mediated transfection such as lipoplex disassembly and DNA release within the cells are believed to take place upon cationic lipid mixing with cellular lipids.\): Cis vs trans fatty acid configurations. Indeed, X-ray structural studies show that the rate of DNA release from lipoplexes as well as transfection activity well correlate with non-lamellar phase progressions observed in cationic PC mixtures with membrane lipids. Lipid phase behavior is known to depend strongly on the chain molecular structure and the above relationships thus substantiate a view that cationic PC phase propensities are an important determinant of their activity. Maximum transfection was observed for ethyl phosphate PCs (EPCs) with monounsaturated 14:1 chains (total of 2 double bonds and 30 chain carbon atoms). A summary of studies on a set of ∼30 cationic PCs reveals the existence of a strong, systematic dependence of their transfection efficiency on the lipid hydrocarbon chain structure: transfection activity increases with increase of chain unsaturation from 0 to 2 double bonds per lipid and decreases with increase of chain length in the range ∼30–50 total number of chain carbon atoms. Similarly to other cationic lipids, they form stable complexes (lipoplexes) with the polyanionic nucleic acids. Examined here is a particularly attractive cationic lipid class, triester phosphatidylcholines (PCs) exhibiting low toxicities and good transfection efficiency. Synthetic cationic lipids are presently the most widely used non-viral gene carriers.
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