Mango fruit ripening is accompanied by increased ethylene production which coordinates
the ripening process. Ethylene production in other fruit has been shown to be
inhibited by acetaldehyde and ethanol. In unripe mango fruit the ethylene production is very
low (tl nl g-l h-l) and treatments with acetaldehyde and ethanol had concentrationdependent
effects on ethylene production. The application of l-aminocyclopropane-lcarboxylic
acid (ACC) to acetaldehyde or ethanol treated fruit discs showed acetaldehyde
to be capable of completely eliminating increased ACC oxidase activity, whereas ethanol
did not. This suggests that acetaldehyde is capable of inhibiting the activity of ACC oxidase
directly, or alternatively of preventing the increase in the enzyme, thereby providing a
possible mechanism for retarding fruit ripening