Vanillic acid is a dihydroxybenzoic acid

Dihydroxybenzoic acid

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

 derivative used as a flavoring agent. It is an oxidized form of vanillin

Vanillin

Vanillin is a phenolic aldehyde, an organic compound with the molecular formula C8H8O3. Its functional groups include aldehyde, ether, and phenol. It is the primary component of the extract of the vanilla bean. It is also found in Leptotes bicolor, roasted coffee and the Chinese red pine...

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

Ferulic acid

Ferulic acid is a hydroxycinnamic acid, a type of organic compound. It is an abundant phenolic phytochemical found in plant cell wall components such as arabinoxylans as covalent side chains. It is related to trans-cinnamic acid. As a component of lignin, ferulic acid is a precursor in the...

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Occurrence in nature

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

Angelica sinensis

Angelica sinensis, commonly known as "dong quai" or "female ginseng" is a herb from the family Apiaceae, indigenous to China.-Chinese:...

,, a herb indigenous to China, which is used in traditional Chinese medicine

Traditional Chinese medicine

Traditional Chinese Medicine refers to a broad range of medicine practices sharing common theoretical concepts which have been developed in China and are based on a tradition of more than 2,000 years, including various forms of herbal medicine, acupuncture, massage , exercise , and dietary therapy...

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Açaí oil

Acai oil

Açaí oil is obtained from the fruit of Euterpe oleracea , 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 acid, protocatechuic acid and ferulic acid as well as -catechin and...

, obtained from the fruit of the açaí palm (Euterpe oleracea), is rich in vanillic acid (1,616 +/- 94 mg/kg).

Metabolism

Vanillic acid is one of the main catechins metabolite

Metabolite

Metabolites are the intermediates and products of metabolism. The term metabolite is usually restricted to small molecules. A primary metabolite is directly involved in normal growth, development, and reproduction. Alcohol is an example of a primary metabolite produced in large-scale by industrial...

s found in humans after consumption of green tea

Green tea

Green tea is made solely from the leaves of Camellia sinensis that have undergone minimal oxidation during processing. Green tea originates from China and has become associated with many cultures throughout Asia. It has recently become more widespread in the West, where black tea is traditionally...

infusions.