Arda Alden Green (May 7, 1899 – January 22, 1958) was an American biochemist who co-discovered the neurotransmitter serotonin and discovered the reaction responsible for firefly bioluminescence.

[2] She then completed her medical studies at Johns Hopkins University, where she worked on electrolyte conductivity in membranes with Leonor Michaelis[6] and graduated in 1927.

[2] In the period from 1930 until 1932, Green conducted research at Woods Hole Oceanographic Institution[7] where she worked with Alfred C. Redfield on respiration in porpoises[8] and a project on hemoglobin in certain fish.

[11] She also isolated and studied, in collaboration with F. M. Bumpus, molecules important in blood pressure regulation including angiotensinogen (the precursor to angiotensin) and angiotonin (hypertension).

[2] Green's career concluded at Johns Hopkins University; she began studying the chemistry of bioluminescence with William D. McElroy at the McCollum-Pratt Institute there in 1953.