Butyric and Fatty Acids

CHEMICAL NAME = butanoic acid CAS NUMBER = 107-92-6 MOLECULAR FORMULA = C4H802 MOLAR MASS = 88.1 g/mol COMPOSITION = C(54.5°/o) H(9.2°/o) 0(36.3%) MELTING POINT = -7.9°C BOILING POINT = 163.5°C DENSITY = 0.96 g/cm3 

Butyric acid is a carboxylic acid also classified as a fatty acid. It exists in two isomeric forms as shown previously, but this entry focuses on n-butyric acid or butanoic acid. It is a colorless, viscous, rancid-smelling liquid that is present as esters in animal fats and plant oils. Butyric acid exists as a glyceride in butter, with a concentration of about 4% dairy and egg products are a primary source of butyric acid. When butter or other food products go rancid, free butyric acid is liberated by hydrolysis, producing the rancid smell. It also occurs in animal fat and plant oils. Butyric acid gets its name from the Latin butyrum, or butter. It was discovered by Adolf Lieben (1836—1914) and Antonio Rossi in 1869. 

Butyric acid is one of the simplest fatty acids. Fatty acids, which are the building units of fats and oils, are natural compounds of carbon chains with a carboxyl group (-COOH) at one end. Most natural fatty acids have an unbranched carbon chain and contain an even number of carbon atoms because during biosynthesis they are built in two carbon units from acetyl coenzyme A (CoA). Butyric acid is an unsaturated fatty acid, which means all carbon-carbon bonds are single bonds. Common names for fatty acids stem from their natural sources. In addition to butyric acid, some other common saturated fatty acids include lauric acid, palmitic acid, and stearic acid. Lauric acid was first discovered in Lauraceae (Laurus nobilis) seeds, palmitic oil was prepared from palm oil, and stearic acid was discovered in animal fat and gets its name from the Greek word stear for tallow. 

Monounsaturated fatty acids have a single carbon-carbon double bond present in the chain, and polyunsaturated fatty acids have more than one carbon-carbon double bond. Oleic 

Butyric acid derivatives play an important role in plant and animal physiology. Gamma-aminobutyric acid (GABA)is the main inhibitory neurotransmitter found in humans and is 

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