beta carotene

n. antioxidant isomeric form of carotene found in dark green and dark yellow vegetables and fruits

Beta-carotene is a form of carotene with β-rings at both ends. It is the most common form of carotene.
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The term carotene is used for several related substances having the formula C40H56. Carotene is an orange photosynthetic pigment important for photosynthesis. It is responsible for the orange colour of the carrot and many other fruits and vegetables. It contributes to photosynthesis by transmitting the light energy it absorbs to chlorophyll.
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Carotene /car·o·tene/ one of four isomeric pigments, having colors from violet to red-yellow to yellow and occurring in many dark green, leafy, and [more]Beta carotene - Community and Resources

Noun
1. an isomer of carotene that is found in dark green and dark yellow fruits and vegetables
(hypernym) provitamin A, carotene, carotin

An antioxidant which protects cells against oxidation damage that can lead to cancer. Beta carotene is converted, as needed, to vitamin A. Food sources of beta carotene include vegetables such as carrots, sweet potatoes, spinach and other leafy green vegetables; and fruit such as cantaloupes and apricots. Excessive carotene in the diet can temporarily yellow the skin, a condition called carotenemia, commonly seen in infants fed largely mushed carrots.