Carnosic acid is a natural

benzenediol In organic chemistry, dihydroxybenzenes (benzenediols) are organic compounds in which two hydroxyl groups () are Electrophilic aromatic substitution, substituted onto a benzene ring (). These aromatic compounds are classed as phenols. There are t ...

abietane Abietane is an organic compound with the formula C20H36. It is a tricyclic, saturated hydrocarbon with an elaborate stereochemistry. It is a colorless solid. It is of little biochemical interest except as a reference structure of the abietanes. ...

diterpene Diterpenes are a class of terpenes composed of four isoprene units, often with the molecular formula C20H32. They are biosynthesized by plants, animals and fungi via the HMG-CoA reductase pathway, with geranylgeranyl pyrophosphate being a primary ...

found in rosemary ('' Salvia rosmarinus'') and common sage (''

Salvia officinalis ''Salvia officinalis'', the common sage or sage, is a perennial, evergreen subshrub, with woody stems, grayish leaves, and blue to purplish flowers. It is a member of the mint family Lamiaceae and native to the Mediterranean region, though it ...

''). Dried leaves of rosemary and sage contain 1.5 to 2.5% carnosic acid. Carnosic acid and carnosol, a derivative of the acid, are used as

antioxidant Antioxidants are Chemical compound, compounds that inhibit Redox, oxidation, a chemical reaction that can produce Radical (chemistry), free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants ...

preservative A preservative is a substance or a chemical that is added to products such as food products, beverages, pharmaceutical drugs, paints, biological samples, cosmetics, wood, and many other products to prevent decomposition by microbial growth or ...

s in food and nonfood products, where they're labelled as "extracts of rosemary" ( E392).

References

{{reflist Phenol antioxidants Diterpenes Phenanthrenes Isopropyl compounds Carboxylic acids Catechols