Commercial notes and scientific information. 21 



Here Rosenthaler is mistaken, as Bourquelot and Herissey 1 ) have shown in their 

 rejoinder to his statements. For amygdalin is not affected by invertin at all, but it is 

 affected by amygdalase, a ferment which differs from invertin. 



It is true that Rosenthaler's dictum was based upon experiments; but, as Bourquelot 

 and Herissey assume, he has, without questioning, employed yeast which contained 

 both invertin and amygdalase, as is often the case. For this reason it is necessary 

 in biological experiments such as carried out by Rosenthaler, first to test the yeast 

 for the presence of amygdalase. We cannot spare the space here to enter into details 

 of the interesting experiments which the authors have carried out with various pre- 

 parations of invertin and with amygdalin. It was clearly shown, however, that pure 

 invertin is incapable of splitting-up amygdalin. 



A paper by Rosenthaler 2 ) on the distribution of emulsin-like enzymes was published 

 afterwards. The older statements with regard to the distribution of emulsin exclusively 

 refer to that constituent which sets free hydrocyanic acid and benzaldehyde from 

 amygdalin. But according to more recent views, emulsin is a mixture of various 

 enzymes which differ in their action and to which different names have been given. 

 Amygdalin is first split up by amygdalase into glucose and mandelonitrile glucosides. 

 The latter is decomposed by prunase 3 ), a /5-glucosidase, into glucose and benzaldehyde 

 cyanohydrin; while the benzaldehyde cyanohydrin, in its turn, is split up by a oxy- 

 nitrilase into benzaldehyde and hydrocyanic acid. The synthesis of optically active 

 nitriles is effected by an oxynitrilese, as Rosenthaler intends henceforth to call the 

 enzyme which he has previously designated by the name of ^-emulsin 4 ). 



Rosenthaler has prepared enzyme-preparations from numerous plants and parts 

 of plants, and has examined them with a view of ascertaining whether they develop 

 similar action as does the almond-emulsin; that is to say whether they decompose 

 amygdalin until hydrocyanic acid appears in the distillate, and whether in synthetical 

 experiments and in the splitting-off of nitrile they yield optically active nitriles 5 ). 



The results obtained by Rosenthaler are as follow: — 

 1. Amygdalin is decomposed by preparations from the following material: 



Seeds of Picinus communis, L., Cydonia vulgaris, Pers., Eryobotrya japonica, Lindl., 



Pirus Malus, L., P. communis, L, Prunus Amygdalus, Stokes var. amara and 



all the other species of Prunus examined, Phaseolus lunatus, L, Physostigma 



venenosum, Balf., Vicia sativa, L., Cucurbita Pepo, L. 

 Fruits of Cannabis sativa, L., Fozniculum vulgare, Miller, Carum Carvi, L., Anethum 



graveolens, L, Conium maculatum, L., (Enanthe Phellandrium, Lmk., Petroselinum 



sativum, L, Sorbus Aucuparia, L, Dolichos Lablab, L, also fruit stalks of Prunus 



Cerasus, L. 

 Flowers of Prunus spinosa, L, Crataegus Oxyacantha, L., Achillea Millefolium, L, 



Matricaria Chamomilla, L., also stigmata of Zea Mays, L. 

 Leaves and herb: Fumaria officinalis, L., Taraktogenos Blumei, Hssk., Sambucus 



nigra, L., Aquilegia vulgaris, L. 

 Barks: Prunus Padus, L. 

 Subterranean organs: Sambucus Ebulus, t I,, , 

 Spores: Linum usitatissimum, L. 

 Sclerotium: Secale cornutum. 



') Journ. de Pharm et Chim. VII. 6 (1912), 246. — 2 ) Arch, der Pharm. 251 (1913), 56. — s ) H. E. and 

 E.F.Armstrong and E. Horton, Proceed. Royal Soc. London, B. 85, 359, 363; Chem. Zentrdlll. 1912, II. 1292. — 

 *) Comp. Report April 1909, 17; October 1909, 19; October 1910, 17. — 5 ) Comp. Report October 1909, 21. 



