Abstract
In the present report, the influence of ultrasonic irradiation on enzyme activities of some vegetables and fruits, especially on the activities of β-amylase and of proteinases such as ficin and papain were observed, and the results are summarized as follows:
1) As to β-amylase, ultrasonic irradiation during enzyme action (20K, C 10 minutes) resulted in a marked fall of the activity to degrade starch. The addition of L-cysteine to β-amylase after the fall of the activity through ultrasanic irradiation failed to restore the activity.
2) β-amylase activity in raw extract of a water melon, tomato, sweet potato and potato showed little fall after ultrasonic irradiation (20K, C 60 minutes). In raw extract of radish, however, some influence was noted. Especially α-amylase activity of radish juice showed a marked decrease.
3) Ficin and papain was activated by reducing agents such as KCN. Activation with KCN after the treatment by ultrasonic irradiation (20K, C 60 minutes), resulted in a considerable augmentation of enzyme activities of ficin and papain. On the contrary, ultrasonic irradiation after activation with KCN resulted in a considerable fall of activity of ficin, but little influence was noted with papain.
