http://www.cfsan.fda.gov/~ear/sea-glow.html
"Several consumers thought their "glowing" seafood was due to phosphorescing phytoplankton, or even fluorescence. The consumers' seafood products "glowing" in the dark were not due to radiation or to fluorescence, which requires an ultraviolet light to trigger the reaction. These seafood products exhibited luminescence due to the presence of certain bacteria that are capable of emitting light. Luminescence by bacteria is due to a chemical reaction catalyzed by luciferase, a protein similar to that found in fireflies."
"Several consumers thought their "glowing" seafood was due to phosphorescing phytoplankton, or even fluorescence. The consumers' seafood products "glowing" in the dark were not due to radiation or to fluorescence, which requires an ultraviolet light to trigger the reaction. These seafood products exhibited luminescence due to the presence of certain bacteria that are capable of emitting light. Luminescence by bacteria is due to a chemical reaction catalyzed by luciferase, a protein similar to that found in fireflies."