Since R. Boyle observed in 1672 that the light emitted by luminescent bacteria is easily inhibited by chemicals, many scientists have done a lot of research on the luminescent effect of bacteria. From 1970s to early 1980s, foreign scientists first isolated and screened luminescent bacteria harmless to human body and sensitive to environment from the surface of marine fish, and used them to detect the biotoxicity of water. Now it has become a simple and rapid biological toxicity detection method. In the early 1980s, this technology was introduced to China, and seawater-type and freshwater-type luminescent bacteria (Vibrio qinghaiensis) were isolated successively, which were used to detect the acute biotoxicity of environmental pollutants.
Luminescent bacteria are generally about 1.5-3um (micron) long and 0.5-0.8um wide, which are invisible to the naked eye. Only when magnified to 1, 000 times with a microscope can their body shape be distinguished. Their luminescence can only be seen under certain conditions. Vibrio qinghaiensis is the only non-pathogenic freshwater luminescent bacteria, so the patented product Vibrio qinghaiensis freeze-dried powder is safe and reliable in transportation and use, and the waste bacterial liquid does not need special treatment and will not cause secondary pollution.