Some fundamental studies were undertaken in order to get some insight into the process of post-ripening of banana by studying the 'changes in carbohyrkare metabolism and the changes in respiratory mechanism during the c o m e of banana ripening.During the course of banana ripening, it is concluded that sucrose is synthesized first directly from starch and subsequently hydrolyzed into glucose and fructose in the post-climacteric stage. In this process phosphorylase appears to be the main enzyme involved in thc breakdown of starch.
2.During the course of post-ripening, water content of the flesh increases gradually. Soluble pectin kcteases four times in the climacteric stage, and then decreases.No peroxidase acLivity is detected through each stage of ripening, but considerable *mcensity of catalase activity is detected. The catalase activity in pre-climacteric banana is stronger than that in the climacteric.
4.The entire terminal oxidst? of preclimacteric banana flesh 'is cyanideresistant, but as the climacteric stage reaches, one-fifth of it becomes cyanide-sensitive. Malonate poisoning appeares to occur to a very little extent.Chrate acts as a substrate toward the respiraLory system of preclimacteric tissue, but as an inhibitor toward that of ripe banana. An interpretation is made on thesz effe$s of citrate.6. With the aid of the uncoupling agent, 2,PdinitrophenoI, it is shown that the respiratory rate of the preclimacteric but' not of the climacteric banana flesh is limited by the capacity of the phosphate transfer system. ATP-ase develops during the course of ripening and appeares to be a factor which put forth the respiratory increase in the climacteric stage. This behavior is belived to be the general feature of the catabolism of reserve substances like starch.
1.Tannin content remains unchanged. 3.
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7Banana i s one of the most abundant fruits in Taiwan There have been many studies on the post-harvcst physiology of fruits('lg), but only a few on biochemistry, I n this investigation, the authors have attempted to get some insight into the process of post-ripening of banana by studying the changes in carbohydrate metabolism and the changes in respiratory mechanism during the course of banana ripening,
M a t e r i a l s and M e t h o d s
SampleT h e species of banana used throughout this experiment was Musa sapientzrm, L., grown at Suei-Li-Kon (7k+g&) in Taiwan.
Respiration measurementA stream of air, freed from carbon dioxide by passing through sodium hydroxide solution, humidified by passing through water, was led over the banana fruit in a respiratory chamber, and then through an absorption tower containing a known quantity of 0.5 N Na0,H.After 'addition of BaCI, solution, the excess alkali was titrated with 0.1 N HCI, using phenolphthalein as indicator.thus determined.T h e amount of CO, evolved was Analysis of the constituent About 30 g of the banana flesh was blended in 95;g ethanol with a wariiig bIendor to destroy the enzymes and to avoid any change of the constituents, and anaIyzed by the usual method...