Aldehyde-enhanced photon emission from crude extracts of soybean seedlings

Abstract

The photon emission from a soybean seedling was remarkably enhanced with the addition of acetaldehyde. The emission spectrum in a seedling had peaks at around 670 and 610–615 nm, with a shoulder at 530–540 nm. In the crude extracts of seedlings, enhancement of photon emission depended on the aldehyde chain length; acetaldehyde gave a maximal photon emission intensity. The photon emission intensity in crude extracts reduced by hydrosulfite showed an initial rapid increase followed by a quick decay in the first phase and a slow decay in the second phase, in the presence of oxygen and aldehyde. The emission spectrum in a whole soybean seedling was observed similarly in crude extracts, with the addition of acetaldehyde. Since a similar photon emission pattern appears in the supernatants of autoclaved extracts, concomitant with the same emission spectra, it is concluded that this photon emission occurs nonenzymatically. Furthermore, when the sample has decayed once photon emission is reduced, the photon emission appears again, upon mixing the sample with oxygen and aldehyde. This result suggests that a hydroperoxide intermediate is an emitter reacting with aldehyde. An energy transfer from triplet carbonyl may not be involved in this reaction.