1981 Volume 50 Issue 3 Pages 379-385
Both acid phosphatase and ribonuclease activities increased markedly in close relation with the climacteric and the subsequent senescence in the pulp tissue of banana (Musa AAA group, Cavendish subgroup cv. Giant Cavendish). fruit The activity of acid phosphatase increased in both supernatant and precipitate obtained by centrifugation at low speed, e.g. 2, 000×g. At an earlier stage of ripening, however, the activity in the precipitate was much higher than that in the supernatant fraction. In the case of ribonuclease, the greater activity was found in the supernatant fraction throughout the period of ripening. Polyacrylamide gel electrophoresis separated acid phosphatase into 9 bands. There were essentially no qualitative differences in isozymes between supernatant and precipitate fractions, nor between unripe and ripe fruis, although some isozymes appeared to increase in activity during ripening. There was a gradual decline in the rate of 14C-leucine incorporation into protein of the pulp tissue of banana fruit during ripening, while there was a sharp increase in ribonuclease and acid phosphatase activities.