Propionic acid displays the general properties of carboxylic acids, and, like most other carboxylic acids, it can form amide, ester, anhydride, and chloride derivatives. It can undergo alpha-halogenation with bromine in the presence of PBr3 as catalyst (the HVZ reaction) to form CH3CHBrCOOH.
Large amounts of propionic acid were once produced as a byproduct of acetic acid manufacture. Current world's largest producer is BASF, with approximately 80 ktpa production capacity.
Propionic acid is produced biologically as its coenzyme A ester, propionyl-CoA, from the metabolic breakdown of fatty acids containing odd numbers of carbon atoms, and also it the breakdown of some amino acids. Bacteria of the genus Propionibacterium produce propionic acid as the end product of their anaerobic metabolism. This class of bacteria is commonly found in the stomachs of ruminants and the sweat glands of humans, and their activity is partially responsible for the odor of both Swiss cheese and sweat.
Propionic acid is also useful as a chemical intermediate. It can be used to modify synthetic cellulose fibers. It is also used to make pesticides and pharmaceuticals. The esters of propionic acid are sometimes used as solvents or artificial flavorings.
A recent publication by MacFabe and colleagues found that intraventricular infusions of propionic acid produced reversible behavior that was very similar to that seen in autism. Behaviors included: hyperactivity, dystonia, turning, retropulsion. In addition, the treated rats demonstrated caudate spiking and the progressive development of limbic kindled seizures. The abstract concludes that this may be an excellent animal model of certain types of autism.
In most vertebrates, propionyl-CoA is carboxylated to D-methylmalonyl-CoA, isomerised to L-methylmalonyl-CoA, and rearranged to yield succinyl-CoA via a vitamin B12-dependent enzyme. Succinyl-CoA is an intermediate of the citric acid cycle and can be readily incorporated there.
In propionic acidemia, propionate acts as a metabolic toxin in liver cells by accumulating in mitochondria as propionyl-CoA and its derivative, methylcitrate, two tricarboxylic acid cycle inhibitors. Propionate is metabolized oxidatively by glia, which suggests astrocytic vulnerability in propionic acidemia when intramitochondrial propionyl-CoA may accumulate. Propionic acidemia may alter both neuronal and glial gene expression by affecting histone acetylation.
Great supply shortage leaves hope to propionaldehyde and propionic acid. (Market Report).(Brief Article)(Statistical Data Included)
Feb 06, 2002; China has not yet achieved the commercialization of propionaldehyde. There is almost no commercial production of propionic acid...
Patent Application Titled "Composition Containing Bacterium Capable of Producing Propionic Acid Bacterium, and Use Thereof" under Review
Nov 20, 2012; By a News Reporter-Staff News Editor at Life Science Weekly -- According to news reporting originating from Washington, D.C., by...