Curcumin \Cur"cu*min\ (-m?n), n. (Chem.)
The coloring principle of turmeric, or curcuma root,
extracted as an orange yellow crystalline substance,
{C14H14O4}, with a green fluorescence.
Note: It possesses acid properties and with alkalies forms
brownish salts. This change in color from yellow to
brown is the characteristic reaction of tumeric paper.
See {Turmeric paper}, under {Turmeric}.