204 EXPERIMENT STATION RECOBD. 



" The pancreatic diastase is extremely sensitive to the action of traces of 

 strong acids, which was shown by experiments with glycerol extracts and 

 hydrochloric acid. Salt is a protection here, as before. The action of the acid 

 is mnch more marked than is that of weak alkali, and neutralization with soda 

 does not bring about recovery. Destruction of the enzym probably follows the 

 contact with acid. The weak inorganic and organic salts present in all pan- 

 creas preparations are important factors in modifying the action of added 

 acids, and doubtless, also, of added alkali. The behavior of phosphates may 

 be of the first importance in this i-egard, especially in the commercial pancrea- 

 tins. which are largely pancreas powders. Without the presence of these salts 

 the addition of the slightest trace of acid would be doubtless much more 

 marked and possibly destructive." 



Inhibition of enzym action by lime-softened waters, O. Bergeim and P. B. 

 Hawk {Jour. Autcr. Chein. Soc, 35 (1913), No. S, pp. 1049-1056).— '' V^'ater 

 softened by the use of lime was found to exert a pronounced inhibitory in- 

 fluence on the action of salivary and pancreatic amylases. This was due largely 

 to the adsorption of the enzyms by colloidal magnesium hydroxid present in 

 these softened waters. 



" That the two enzyms used in these tests, sjilivary and pancreatic amylases, 

 are not identical is indicated by differences shown in their response to the action 

 of various ingredients contained in hard and softened waters." 



The occurrence of maltase in cereals, Z. Wierzchowski {Bioehem. Ztschr., 

 51 (1913), Xo. 1-2, PI). 125-131). — In some previous work it was shown that 

 com contains most of its maltase in an insoluble form. The investigation has 

 now been extended to wheat, rye, barley, oats, millet, and buckwheat, corn 

 being used for a comparison. AU of the cereals were extracted with water until 

 freed from diastase. 



As regards the maltase content, the cereals can be conveniently divided into 

 two groups. The first contains only small amounts of maltase and consists of 

 rye, barley, wheat, and oats; the second group contains the cereals which have 

 a large quantity of maltase and is made up of millet, corn, and buckwheat. 

 Buckwheat and millet yield only small amounts of maltase when extracted 

 with water. 



The enzyms of the tobacco plant, J. DU P. Oosthuizen and O. M. Shedd 

 (Jour. Aiiier. Chew. Soc, 35 (1913), No. 9, pp. 1289-1309) .—X study is reported 

 from the Kentucky Experiment Station as to the occurrence of enzyms in 

 the Burley tobacco, from the Burley region, and the dark types grown in western 

 Kentucky. 



" It appears that invertase, diastase, emulsin, and reductases are present in 

 appreciable amounts in the tobacco seed and in the leaf in all stages of its 

 growth and after curing. Lipase, inulase. and a pi'oteolytic enzym also seem to 

 be present in small amounts, although in some cases the results are doubtful. 

 The tests for enzyms in the soil were negative with one or two exceptions. 

 Oxidases were found in the green leaf in all stages of its growth, gradually 

 decreasing in amount from the topping stage to maturity, but no definite tests 

 were obtained for this enzym in the cured leaf. A fairly good test, however, 

 was obtained with guaiacum in the leaf cured with a green color, but here, as 

 well as in the other cured samples, no tests were obtained with phthalin. 

 This may be due either to the fact that the enzym has been used up in the 

 cured leaf for oxidation purposes or that some interfering color prevented a 

 positive test from being obtained. 



" The fact that the quantitative tests for the amount of oxidase reaction 

 show the smallest amount in the leaf at about the matured stage, taken in 

 connection with the fact that the active extracts of the cured leaf which gave 



