AGRICULTURAL CHEMISTRY — AGROTECHNT. 203 



the formula may be written as CioH,(OH«) (COOH),. It is therefore quite dif- 

 ferent from j8-resorcyl-carbonic acid, and so far as the author linows, the occur- 

 rence of such an acid in fungi has never been mentioned before." The name 

 koji acid has since been given to the substance. 



In regard to the proteolytic activity of taka-diastase, Olga Szant6 (Bio- 

 chem. Ztschr., J,:l {1912), No. 1-2, pp. 31-J,3).— The results show that acids in 

 smnll concentrations affect the action of tal^a-diastase, mineral acids having the 

 least effect. Compared with trypsin, it is more susceptible to organic acids, 

 and hydrochloric acid destroys it more quickly. 



Inhibition is less by alkalis than by acids, and alkalis do not destroy it. 

 Salts do not, or only slightly, inhibit its action. Neutral salts, such as sodium 

 chlorid, sodium sulphate, and sodium nitrate, do not affect it, but inhibit the 

 activity of trypsin. The same effect was noted with most organic salts, but 

 not with sodium lactate. Dextrose, lactose, and starch do not affect it, while 

 levulose shows a slight inhibition of its activity. 



The nature and function of the plant oxidases, E. D. Clark {Torrcyn, 11 

 (1911), Nos. 2, pp. 23-31; 3. pp. 55-61; Jf, pp. 84-92; 5, pp. 101-110).—" The oxi- 

 dases are of very wide distribution among the flowering plants, peroxidases, 

 especially, being present in about 75 per cent of all the specimens examined, 

 while oxygenases (direct oxidases) are less widely distributed, being found in 

 one-half of the plants used. Catalase may be said to be universally distributed, 

 since there were only a few cases in which it was not found. The leaves, stems, 

 roots, and food-storage organs of the plants seemed to contain the greatest 

 amounts of the oxidases. The flowers and fruit were in many cases compara- 

 tively poor in oxidases. In regard to the fruits this statement must be qualified, 

 because dry seeds of somewhat uncertain age were the only available material 

 of certain species. 



" Our experience with a great many parallel tests, using the different oxidase 

 reagents upon a great variety of vegetable tissues, show that all of the reagents 

 seem to detect the same substance or substances, for if one reagent gave a posi- 

 tive test, the others generally acted in like manner. The phenolphthalein and 

 indophenol reagents gave positive results in more cases than the others. This is 

 undoubtedly due to their greater ease of oxidation, for they are spontaneously 

 oxidized by the air. It is probable that in the presence of acid juices in the 

 plant the latter does not form oxidases or else that they are immediately de- 

 stroyed by the acid. It was shown that the inhibiting effect of acids upon the 

 action of oxidases seemed to be a function of the concentration of the hydrogen 

 ions. 



"Among plants the chromogens are found to the greatest extent in certain 

 orders, such as the Liliales, Orchidales, Ranales, and most frequently of all 

 in the ^tex plants of the Convolvulacere, Boraginacere, Labiatre. Solanace.^, 

 Rubiaceie, Composit<ia, etc. Active oxidases are also likely to be associated with 

 chromogens in the latex plants. These conclusions are interesting because of the 

 bearing they have upon Palladin's theory that these chromogens play an impor- 

 tant part in the respiration and the metabolism of plants." 



A comprehensive review of the literature of the oxidases is included. 



Investigations in regard to phosphatese, H. von Euler (Abs. in Chem. Ztg., 

 36 (1912), Xo. 138, p. 1353).— This enzym has the property of combining inor- 

 ganic phosphoric acid with carbohydrates, forming an organic phosphoric acid 

 ester, glucophose. Glucophose was cleaved both in the intestine and kidney, 

 and was synthesized with extracts of these organs. 



Glucophose is considered a catalyzer for sugar cleavage by living j-east and 

 also an intermediary product of this reaction. Judging from this phenomenon 

 it seems reasonable to assume that the cleavage of sugar in the animal organ- 



