Systematic Studies of Biophoton as Biological Information in the Optical Region

Abstract

Biochemically generated electronically excited states are ubiquitous in living systems and the light such states emit can be utilized to probe the underlying processes and activities involved. Aside from the well known and understood bioluminescence found in fireflies, bacteria, sea creatures, etc., there is a less well understood emission from almost all animal and plant tissues, cells and organs characterized by its extreme weakness, ranging in intensity from perhaps a few to about 10³ – 10⁴ photons per second per cm² of sample [1], [2]. These phenomena of ultraweak light emission which are closely related to the process of life and biological activities, named simply biophoton emission, seem to have no specific sources such as associated with visible bioluminescence as described in the previous paper [3] (referred hereafter as Paper I). They are believed to appear rather broadly in nature in conjunction with a variety of biochemical and biophysical processes and biological functions.