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n. A chemical substance present in the cells of bioluminescent organisms, such as fireflies, that produces an almost heatless, bluish-green light when oxidized under the catalytic effects of luciferase and ATP.

n. Any of a class of polycyclic heterocycles that are responsible for the bioluminescence of fireflies, being converted to oxyluciferin by luciferase in the process.

n. any of several substances found in luminescent organisms (such as the firefly, Photinus pyralis) which, when oxidized, produces an almost heatless light. It was first isolated from fireflies, and is the source of the firefly luminescence. See also firefly luciferin

n. pigment occurring in luminescent organisms (as fireflies); emits heatless light when undergoing oxidation

"He told me that luciferin is extremely unstable and rapidly decomposes in the presence of oxygen, and also that Professor Newton Harvey of Princeton University had been trying to purify luciferin for the past 20 years but had been unsuccessful."

animal pigment   

firefly luciferin