N-PROPYL GALLATE IS AN INHIBITOR TO TOMATO FRUIT RIPENING

Abstract

The effects of n-propyl gallate (nPG) on postharvest ripening of tomato have been studied. Mature green (MG) stage tomatoes were harvest and treated with 0.5 mM nPG at 25 ± 1C for 12 h. Following the nPG treatment, fruit ripening was delayed by at least 7 days. Cyanide-resistant respiration and ethylene production were suppressed significantly at the first 7 days. nPG treatment decreased levels of H2O2 and increased activities of antioxidant enzymes and chemicals, particularly for superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (GPX) and ascorbic acid (AsA). The decreases of flesh firmness and total chlorophylls were inhibited, and the production of soluble sugars and lycopene were suppressed by nPG either. Alternative oxidase (AOX) and cyanide-resistant respiration play important roles in fruit climacteric and may be correlated with system 2 ethylene production. nPG could be used as an efficient inhibitor to tomato fruit ripening. PRACTICAL APPLICATIONS Control of fruit ripening is of enormous commercial importance. Generally, tomato fruit ripening is controlled through the use of gas, temperature and humidity control. This research has focused on the application of n-propyl gallate (nPG) on postharvest ripening of tomato fruit. The results of the study have implied that nPG treatment could obviously prolong the shelf life and keep the postharvest quality of tomato fruits, and the firmness loss, respiration rate and ethylene production could be better suppressed compared with the control fruits, which shows that nPG is a potentially effective and safe inhibitor for climacteric fruits ripening, such as tomato. Utilization of the results of this research is likely to benefit for the storage technological improvement.