414 EXPERIMENT STATION RECORD. [Vol.35 



A direct cleavage of glucose from starch never occurs. The action of the 

 enzyms of germinated barley on starch is very similar to that of taka-diatase, 

 the latter, hovv^ever, being richer than the barley in maltose-forming enzyms, 

 so that the dextrin stage is passed through more rapidly. In either case the 

 glucose is formed by the action of maltase on maltose. . In determining the 

 diastatic activity of plant material in preparations such as taka-diatase and 

 pancreatins the presence of maltase should be taken into account. 



The distribution of maltase in plants. — II, The presence of maltase in 

 foliag'e leaves, A. J. Daish (Biochem. Jour., 10 (1916), No. 1, pp. Jt9-55). — The 

 presence of maltase in the leaves of Tropseolum, potato, dahlia, turnip, sun- 

 flower, and mangold, whether picked at night or in the daytime, has been 

 demonstrated by the production of reducing sugars through the action of 

 macerated leaves on soluble or gelatinized starch. In the presence of an excess 

 of starch the conversion is generally incomplete. Under these conditions the 

 action of the endocellular maltase is limited because of its low solubility and 

 power of diffusion. On this account maltose is nearly always found among the 

 products. 



The distribution of maltase in plants.— Ill, The presence of maltase in 

 g'erminated barley, A. J. Daish {Biochem. Jour., 10 (1916), No. 1, pp. 56-76, 

 fig. i).— The presence of maltase which hydrolyzed maltose to glucose in air- 

 dried germinated barley was demonstrated by allowing the finely powdered 

 grains to act on starch or maltose at 38° C. The action on starch is very 

 similar to that of taka-diastase, which contains maltase in addition to the 

 ordinary diastatic enzyms. 



The action on germinated barley probably takes place in the following series 

 of stages: Starch— ^soluble starch-^dextrins^maltose — >glucose. 



The self-digestion of the barley starch is largely inhibited during the process 

 of digestion of added starch until the greater part of the latter is converted 

 into glucose. A correction for the enzymic material used, therefore, can not be 

 applied by carrying out a control in the presence of water alone. 



In the digestion of gelatinized starch by germinated barley dextrin, maltose, 

 and glucose are found even after prolonged periods. The glucose steadily in- 

 creases, however, in amount during the whole period of digestion, with a 

 consequent decrease of the other saccharids. 



Observations on beet and potato tyrosinase, M. Gonneemann (Chem. Ztg., 

 40 (1916), No. 16-17, pp. 127, i28).— The author has demonstrated that the 

 tyrosinase prepared from the potato pos.sesses agglutinating properties which 

 are specific for sheep corpuscles. The tyrosinase from beet juice possessed no 

 agglutinating property but was hemolytic. This latter property is attributed 

 to the presence of saponins which are so combined with the enzym as to 

 make their complete separation impossible. The presence of the saponin was 

 established by confirmatory tests. The potato tyrosinase used was a glycerin 

 extract 14 years old but as active as a fresh preparation. 



The enzyms of cacao, H. C. Beill (Philippine Jour. Sci., Sect. A, 10 (1915), 

 No. 2, pp. 123-133). — "The pulp surrounding the cacao bean contains a greater 

 number of enzyms than the fre.sh bean itself. The pulp shows activity for the 

 enzyms casease, protease, oxidase, raflinase, and invertase. The fresh bean 

 gave reactions for casease and raffinase, and very strong reactions for oxidase. 

 The fermented bean reacted for casease, protease, oxidase, diastase, raffinase, 

 and invertase." 



Protease and invertase were present in the fermented bean as well as in the 

 pulp, but were absent in the fresh bean. It is indicated that these enzyms must 

 have penetrated the membrane surrounding the bean during fermentation. 

 Diastase was also present in the fermenting bean, which was probably devel- 



