Potassium 7-hydroxy-1-naphthalenesulfona

Potassium 7-hydroxy-1-naphthalenesulfona (2-Naphthol-8-sulfonic Acid Potassium Salt) is naturally present in the fruit of the Rubiaceae gardenia, the flowers of the Iridaceae crocus, and the flowers and leaves of the Scrophulariaceae Scrophulariaceae.