Vanillic acid (4-hydroxy-3-methoxybenzoic acid) is a

dihydroxybenzoic acid Dihydroxybenzoic acids (DHBA) are a type of phenolic acids. There are six main compounds, having all the same molecular formula C7H6O4. Those are: * 2,3-Dihydroxybenzoic acid (2-Pyrocatechuic acid or hypogallic acid) * 2,4-Dihydroxybenzoic acid ...

derivative used as a flavoring agent. It is an

oxidized Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is ...

form of

vanillin Vanillin is an organic compound with the molecular formula . It is a phenolic aldehyde. Its functional groups include aldehyde, hydroxyl, and ether. It is the primary component of the ethanolic extract of the vanilla bean. Synthetic vanillin ...

. It is also an intermediate in the production of vanillin from

ferulic acid Ferulic acid is a hydroxycinnamic acid derivative and a phenolic compound. It is an organic compound with the formula (CH3O)HOC6H3CH=CHCO2H. The name is derived from the genus '' Ferula'', referring to the giant fennel ('' Ferula communis''). Cl ...

Occurrence in nature

The highest amount of vanillic acid in plants known so far is found in the root of ''

Angelica sinensis ''Angelica sinensis'', commonly known as ''dong quai'' () or female ginseng, is a herb belonging to the family Apiaceae, indigenous to China. ''A. sinensis'' grows in cool high altitude mountains in East Asia. The yellowish brown root of the plan ...

'', an herb indigenous to China, which is used in

traditional Chinese medicine Traditional Chinese medicine (TCM) is an alternative medicine, alternative medical practice drawn from traditional medicine in China. A large share of its claims are pseudoscientific, with the majority of treatments having no robust evidence ...

Occurrences in food

Açaí oil Açaí oil is obtained from the fruit of ''Euterpe oleracea'' (açaí palm), which grows in the Amazon rainforest. The oil is rich in phenolic compounds similar in profile to the pulp itself, such as vanillic acid, syringic acid, p-hydroxybenzoic ...

, obtained from the fruit of the açaí palm (''

Euterpe oleracea Euterpe (; , from + ) was one of the Muses in Greek mythology, presiding over music. In late Classical times, she was named muse of lyric poetry. She has been called "Giver of delight" by ancient poets. Mythology Euterpe was born as one of t ...

''), is rich in vanillic acid (). It is one of the main natural phenols in

argan oil Argan oil is a Vegetable fats and oils, plant oil produced from the kernels of the argan tree (''Argania spinosa'' L.), which is indigenous to Morocco and southwestern Algeria. In Morocco, argan oil is used to dip bread at breakfast or to driz ...

. It is also found in

wine Wine is an alcoholic drink made from Fermentation in winemaking, fermented fruit. Yeast in winemaking, Yeast consumes the sugar in the fruit and converts it to ethanol and carbon dioxide, releasing heat in the process. Wine is most often made f ...

and

vinegar Vinegar () is an aqueous solution of diluted acetic acid and trace compounds that may include flavorings. Vinegar typically contains from 5% to 18% acetic acid by volume. Usually, the acetic acid is produced by a double fermentation, converting ...

Metabolism

Vanillic acid is one of the main

catechins Flavan-3-ols (sometimes referred to as flavanols) are a subgroup of flavonoids. They are derivatives of flavans that possess a 2-phenyl-3,4-dihydro-2''H''-chromen-3-ol skeleton. Flavan-3-ols are structurally diverse and include a range of comp ...

metabolite In biochemistry, a metabolite is an intermediate or end product of metabolism. The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, c ...

s found in humans after consumption of

green tea Green tea is a type of tea made from the leaves and buds of the '' Camellia sinensis'' that have not undergone the withering and oxidation process that creates oolong teas and black teas. Green tea originated in China in the late 1st millenn ...

infusions.

Synthesis

Vanillic acid can be obtained from the oxidation of

by various oxidizing agents. With Pd/C, NaBH₄, and KOH as the oxidizing agent, the conversion was reported to occur in ~89% yield.

References

{{Gallotannin Flavors Dihydroxybenzoic acids Gallotannins Vanilloids Phenol ethers