Pharmaceutical companies commonly include propionic acid in the formulation of steroidal and nonsteroidal anti-inflammatory (NSAIDS) medications. In low doses, manufacturers use the acid as a preservative and as an antimicrobial agent in foods produced for human consumption. These preservative properties of this carboxyl acid also make the compound’s use in foods created for livestock and poultry advantageous.
Propionic acid is a saturated fatty acid with three carbon molecules and is produced naturally by certain bacteria during fermentation. The compound may also be synthetically created using ethylene or natural gas. In their natural state, propionates are a colorless, oily liquid having a pungent odor. When used as a calcium or sodium salt, propionic acid may be colorless, white and crystallized, or in a powdered form that readily dissolves in water or alcohol.
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Researchers believe that propionic acid can also inhibit prostaglandin synthesis. Pharmaceutical companies commonly include it as an ingredient in NSAIDS. Aspirin, ibuprofen, and other over-the-counter and prescription anti-inflammatory preparations commonly contain propionic acid as an ester. In this form, the compound attaches to the medication’s active ingredients.
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Fluticasone inhalers used for respiratory conditions commonly contain propionic acid. The compound frequently accompanies steroid medications, including testosterone. Physicians commonly prescribe the formulation for breast cancer and hormone replacement therapy. Some antihistamine and decongestant combinations also contain chains of the acid.
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Studies indicate propionic acid affects the amount of usable medication circulating in the body. Without an ester group, many medication levels peak in the bloodstream. Blood levels then rapidly decrease as the body eliminates the drug. When combined with the acid, steroids and other medications remain in the body for longer periods of time.
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The acidic properties of propionates provide antimicrobial activity against some bacteria. Propionic acid is more commonly used for fungal and mold growth prevention. Its acidic nature allows it to penetrate the cells of microorganisms, and after gaining entrance into the cytoplasm, the acid decreases the cellular pH. This inhibits normal cell function and growth, causing death. These properties make the substance useful for preserving food products.
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Industrial bakers commonly include propionic acid in a calcium or sodium salt form as a mold deterrent. Manufacturers incorporate it into the batter of breads, cakes, and other baked goods. The cheese industry also uses propionic acid in processed products. Livestock and poultry food manufacturers include it as a preservative, while farmers and ranchers often add the compound to animal drinking water.