Violaxanthin is a natural xanthophyll pigment with an orange color found in a variety of plants including pansies. It is biosynthesized from zeaxanthin by epoxidation. As a food additive it used under the E number E161e as a food coloring. Xanthophylls (originally phylloxanthins) are yellow pigments from the carotenoid group. The name is from Greek xanthos ( , "yellow") + phyllon ( , "leaf"), due to their contribution to the yellow band in early chromatography of leaf pigments. Their molecular structure is similar to carotenes, but they have oxygen atoms. Thus, they are carotenoids but no longer carotenes.