What Is Lycopene?

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ycopene is a red pigment found in plants and is part of a large class of plant compounds called carotenoids. Carotenoids are fat soluble, and create yellow, orange, or red colors in plants. Carotenoids are not made by humans. Lycopene is not found in high amounts in many plants. The greatest sources of lycopene in fresh fruits and vegetables are watermelon, tomato, red grapefruit, guava, and wild fruits from Asia and Russia.

The red color found in strawberries, cherries, etc., is a water-soluble pigment called anthocyanin, and is formed by a very different pathway from the carotenoids.

The primary role of carotenoids in plants is to neutralize compounds created during photosynthesis. These compounds, often hydrogen peroxide or singlet oxygen, both attack and destroy cell membranes, ultimately damaging the cell. Singlet oxygen or free oxygen radicals are one-half of an oxygen molecule (O).

Humans breathe in oxygen as O₂. The biological processes in the body use oxygen for reactions, frequently creating singlet oxygen as a by-product. The singlet oxygen is very reactive (high electric charge) and, therefore, must be eliminated by the body before cell damage occurs. The body has antioxidant (anti-oxygen) compounds that look for free oxygen particles and neutralize them. Of the carotenoids, lycopene is the most effective oxygen scavenger because it can neutralize several oxygen particles with one lycopene molecule. Other antioxidants are Vitamin C (ascorbic acid) and Vitamin E.

Watermelon contains 15 to 20 milligrams of lycopene per 2-cup serving. Besides containing lycopene, watermelon is a source of potassium (116 mg/100g compared to 396mg/100g in banana and 222mg/100mg in tomato), and Vitamin A (366 IU/100g compared to 623 IU/100g in tomato). Watermelon also contains Vitamin C, (10mg/100g in tomato).