Phenolic compounds are one of the most important compounds with an important role in growth and reproduction, providing protection against pathogens and predators, and they could be the main determinant of antioxidant potential of foods. They also contribute towards the color and sensory characteristics of fruits and vegetables. Different classes of phenolic compounds in plants are Simple phenolics, Benzoquinones; Hydroxybenzoic acids; Acetophenones, phenylacetic acids; Hydroxycinnamic acids, phenylpropanoids; Napthoquinones; Xanthones; Stilbenes, anthraquinones; Flavonoids, isoflavonoids; Lignans, neolignans; Biflavonoids; Lignins; and Condensed tannins. Hydroxybenzoic acids gallic acid, and Protocatechuic acid. Hydroxycinnamic acids are p-coumaric acid, caffeic acid, ferulic acid, sinapic acid, and other components such as coumarins (Umbelliferone, Esculetin, Scopoletin, Resveratrol, Piceatannol, Pterostilbene), curcuminoids (Curcumin, Demethoxycurcumin, Bisdemethoxycurcumin), condensed tannins or proanthocyanidins (Procyanidin B1), and lignan (Sesamin).