Changes in chlorophyll fluorescence and enzyme activity for scavenging of free radicals in banana fruits stored at low temperatures.
Chaiprasart, P., Gemma, H. and Iwahori, S.
Japanese Journal of Tropical Agriculture. Volume 45, Number 3, 2001. Pages 181-191.
2001
บทคัดย่อ
A study was undertaken to determine the chlorophyll fluorescence and the enzyme activity for scavenging of free radicals in banana cv. Cavendish fruits kept at chilling temperatures and fruit physiological changes and to clarify the process of chilling injury. Banana fruits at the mature green stage were stored at 5, 13 and 20 deg C, respectively, for comparative studies. Fruits stored at 20 and 13 deg C reached the ripening stage after 2 and 3 weeks of storage, respectively, based on the rapid increase in the respiration and ethylene evolution rates, colour change, firmness of peel and pulp, and chlorophyll fluorescence. In contrast, fruits stored at 5 deg C showed slightly higher respiration and ethylene evolution rates, and a marked increase of CO2 production when transferred to 20 deg C, after 2 weeks of storage, indicating the presence of chilling injury symptoms. The Fv/Fm ratio of the fruits stored at 5 deg C for 2 weeks was lower than that of fruits stored at 13 and 20 deg C. In addition, chlorophyll fluorescence measurement could be used to predict the occurrence of chilling injury for banana fruits as a non-destructive method of measurement before tissue damage becomes visible. Superoxide dismutase, catalase and peroxidase activities of the fruits stored at 5 deg C and subsequently transferred to 20 deg C were higher than those of the fruits stored at 13 and 20 deg C, respectively, when chilling injury symptoms occurred.