Carotenoids are the most common pigments in nature and can be red, orange, yellow, or purple. Carotenoids are essential for photosynthesis and photo-protection in plants. They harvest light energy and transfer it to chlorophylls and are involved in the assembly of photosystems. Carotenoids are also found in non-photosynthetic organs of plants, such as seeds, fruits, flowers, pericarps, and roots.