Linoleic acid in the context of Polyunsaturated fatty acid

Castor oil is a vegetable oil pressed from castor beans, the seeds of the plant Ricinus communis. The seeds are 40 to 60 percent oil. It is a colourless or pale yellow liquid with a distinct taste and odor. Its boiling point is 313 °C (595 °F) and its density is 0.961 g/cm. It includes a mixture of triglycerides in which about 90 percent of fatty acids are ricinoleates. Oleic acid and linoleic acid are the other significant components.

Some 270,000–360,000 tonnes (600–800 million pounds) of castor oil are produced annually for a variety of uses. Castor oil and its derivatives are used in the manufacturing of soaps, lubricants, hydraulic and brake fluids, paints, dyes, coatings, inks, cold-resistant plastics, waxes and polishes, nylon, and perfumes.

Essential fatty acids, or EFAs, are fatty acids that are required by humans and other animals for normal physiological function that cannot be synthesized in the body.⁠ As they are not synthesized in the body, the essential fatty acids – alpha-linolenic acid (ALA) and linoleic acid – must be obtained from food or from a dietary supplement. Essential fatty acids are needed for various cellular metabolic processes and for the maintenance and function of tissues and organs. These fatty acids also are precursors to vitamins, cofactors, and derivatives, including prostaglandins, leukotrienes, thromboxanes, lipoxins, and others.

Only two fatty acids are known to be essential for humans: alpha-linolenic acid (an omega−3 fatty acid) and linoleic acid (an omega−6 fatty acid). These are supplied to the body either as the free fatty acid, or more commonly as some glyceride derivative. ALA can be converted into eicosapentaenoic acid and docosahexaenoic acid, but the conversion amount is small, requiring intake from food or supplements. Deficiency in omega−3 fatty acids is very common. The average American has a dietary ratio between omega−6 fatty acids and omega−3 fatty acids of 20:1.

Emu oil is an oil derived from body fat harvested from certain subspecies of the emu, Dromaius novaehollandiae, a flightless bird indigenous to Australia.

Unadulterated emu oil can vary widely in colour and viscosity anywhere from an off-white creamy texture to a thin yellow liquid, depending on the diet of the emu and the refining method(s) used. Industrially refined emu oil is composed of a minimum of 70% unsaturated fatty acids. The largest component is oleic acid, a monounsaturated omega-9 fatty acid. Emu oil also contains roughly 20% linoleic acid (an omega-6 fatty acid) and 1–2% linolenic acid (an omega-3 fatty acid). Fully refined emu oil has a bland flavour.

A sunflower seed is a seed from a sunflower (Helianthus annuus). There are three types of commonly used sunflower seeds: linoleic (most common), high oleic, and sunflower oil seeds. Each variety has its own unique levels of monounsaturated, saturated, and polyunsaturated fats. The information in this article refers mainly to the linoleic variety.

For commercial purposes, sunflower seeds are usually classified by the pattern on their husks. If the husk is solid black, the seeds are called black oil sunflower seeds. The crops may be referred to as oilseed sunflower crops. These seeds are usually pressed to extract their oil. Striped sunflower seeds are primarily eaten as a snack food; as a result, they may be called confectionery sunflower seeds.

Dihomo-γ-linolenic acid (DGLA) is a 20-carbon ω−6 fatty acid (also called, cis,cis,cis-8,11,14-eicosatrienoic acid). In physiological literature, it is given the name 20:3 (ω−6). DGLA is a carboxylic acid with a 20-carbon chain and three cis double bonds; the first double bond is located at the sixth carbon from the omega end. DGLA is the elongation product of γ-linolenic acid (GLA; 18:3, ω−6). GLA, in turn, is a desaturation product (Delta 6 desaturase) of linoleic acid (18:2, ω−6). DGLA is made in the body by the elongation of GLA, by an efficient enzyme which does not appear to suffer any form of (dietary) inhibition. DGLA is an extremely uncommon fatty acid, found only in trace amounts in animal products.