Rosmarinic acid

Rosmarinic acid, C18H16O8, is a natural polyphenol antioxidant carboxylic acid found in many Lamiaceae herbs used commonly as culinary herbs such as lemon balm, rosemary, oregano, sage, thyme and peppermint. Chemically, rosmarinic acid is an ester of caffeic acid with 3,4-dihydroxyphenyl lactic acid. It is a red-orange powder that is slightly soluble in water, but well soluble in most organic solvents. Biological importance Because of the antioxidant activity of Lamiaceaeous