Abstract
1. The pH of optimal activity for gelatin, casein and peptone hydrolysis by ficin is from 4 to 5.
2. Dipeptides are not split by ficin.
3. In the enzymatic hydrolysis of DL-leucyldiglycine at pH 4.5 the isolation of leucine suggests a catheptic aminopeptidase action of ficin.
4. Likewise, the isolation of hippuric acid from benzoyldiglycine digestate leads to the assumption of the presence of a catheptic carboxypeptidase in ficin.
5. In the action of ficin there is no indication of hippuricase and acylase action.
6. The fig sap and also pepsin-treated sap have the vermicidal effect dissolving the worm body, while the boiled sap or pancreatin has no such effect. The anthelmintic ability of ficin is resistant against the digestion by pepsin and pancreatin (8), but it is inac-tivated by heating in boiling water for 5 minutes.
Grateful acknowledgement is made to Prof. S. Utzino for his suggestive discussion of this subject as well as for his perusal and comment of the manuscript.
This investigation has been supported by a grant from the Ministry of Education for Scientific Research, for which the author wishes to express his sincere thanks.
