Abstract <p>Aliphatic aldehydes are involved in many important biological processes, but detection of them at low concentrations requires expensive laboratory equipment and labor-intensive analytical methods. Typically, chromatographic and chromatograph mass spectrometric methods are used for this purpose. Therefore, developing a simple method for detecting aldehydes at low concentrations is a pressing scientific and technical challenge. We have demonstrated that a bacterial bioluminescent system can be effectively used for the semiquantitative determination of biogenic aldehydes in vitro at nanomolar concentrations. Furthermore, this system holds promise for detecting biogenic aldehydes in vivo.</p>