Linoleic acid is a polyunsaturated omega-6 fatty acid with formula HOOC(CH2)7CH=CHCH2CH=CH(CH2)4CH3. It is a colorless liquid, insoluble in water but soluble in organic solvents. First isolated from linseed oil by F. Sacc in 1844
Fatty acids are carboxylic acids found in fats, oils, and most lipids. They typically contain 12-20 carbon atoms and are unbranched. Fatty acids can be saturated, monounsaturated, or polyunsaturated. Natural fatty acids are generally in cis configuration
Phospholipids are main components of cell membranes. Each phospholipid contains two fatty acids, phosphate group, and glycerol. Phosphate group head is hydrophilic, fatty acid tails are hydrophobic
Colorless to pale yellow liquid with mild lard-like odor. Floats on water with density 0.89 at 77°F. Boiling point 547°F at 100 mmHg. Melting point 61.3°F. Flash point 372°F
Colorless to straw-colored liquid with boiling point of 444-446°F. Melting point of 23°F, less dense than water. Insoluble in water, soluble in ether and absolute alcohol. Density of 0.9007 g/cu cm at 72°F
PA is the most common saturated fatty acid in human body, accounting for 20-30% of total fatty acids. PA is found in palm oil (44%), meat, dairy (50-60%), cocoa butter (26%), and breast milk (20-30%). PA tissue content is tightly controlled, with intake not significantly affecting tissue concentration