Bio-luminescence is the light produced by a chemical reaction taking place inside a living organism. Generally, bioluminescence is widely found in deep sea organisms.
This action occurs when the enzyme luciferase reacts with the luciferin compound to produce illumination in the presence of oxygen.
Many marine organisms such as sponges, jellyfish, insects, some species of fish, arthropods, echinoderms and unicellular algae exhibit bioluminescence either to avoid predators or to attract prey.
The most likely cause of the bio-luminescence incident in Visakhapatnam is algal blooms in dinoflagellate species of Noctiluca and Ceratium.