ASCORBATE CONTENT AND PEROXIDASE ACTIVITIES IN APPLE FRUITS DURING STORAGE

摘要

Ascorbate content and activities of ascorbate and guaiacol peroxidases in the three cultivars of apples stored under different conditions were studied. One set to the apples was stored at 4°C in normal atmosphere without humidity control (variant I).The other set was stored for 5 months in controlled atmosphere ((3% O'2, 5% CO_2, RH 90%) at 3°C and then transferred to the conditions identical with those for the first group (variant II). The ascorbate content and enzyme activities depended on the cultivars and the conditions of storage. At the beginning of experiment in variant I in all the cultivars the concentrations of total ascorbate were similar to those in invariant II, but those of dehydoascorbate were lower in variant I. Thereafter the concentration of dehydoascorbate increased more in 'Jonagold' and 'Golden Delicious' cultivars than in 'Shampion'. The ascorbate and guaiacol peroxidase activities were higher in 'Shampion' cultivar. The results showed that conditions of storage significantly influenced the antioxidant metabolism in different apple cultivars. 'Shampion' was the best source of ascorbate in the case of long-stored apples.