Evening primrose is a biennial herbaceous plant of the Onagraceae family. Characterized by fragrant yellow flowers that open at dusk, it is nicknamed "evening primrose" and "belle de nuit". The fruit contains small black seeds that are very rich in fatty acids, from which evening primrose oil is extracted.

Evening primrose is native to North America. Native Americans cultivated this plant for its medicinal properties. They notably used evening primrose in poultice form against skin conditions. Evening primrose arrived in Europe in the 17th century. Presented under the name "king's panacea", it quickly became a popular remedy.

Evening primrose oil also contains:

• oleic acid (Omega 9),
• vitamin E,
• phytosterols
• triterpenic acids.

Borage is an herbaceous plant of the Boraginaceae family, characterized by their cover of short, stinging hairs. Borage is native to North Africa and is recognized by its star-shaped blue flowers. Its name comes from the Arabic abou rash, translated as "Father of sweat" in reference to borage's supposed sudorific virtue.

Borage seeds contain:

• polyunsaturated fatty acids: linoleic and gamma-linolenic acid (omega 6), linolenic acid (omega 3)
• monounsaturated fatty acid of the omega 9 type: oleic acid
• saturated fatty acids: stearic and palmitic acid