198 F. Petrak: Pilze 1921 (ohne die Schizomyceten und Flechten) [38 



242. Karrer Joanne L. Studies in the pliysiology of the fungi. 

 XIII. The effect of Hydrogen-Ion Concentration upon the Accu- 

 miilation and Activation of Amylase produeed by certain Fungi. 

 (Ann. of the Missouri Bot. Gard. VIII, 1921, p. 63 — 96.) — Zusammenfassung: 

 1. A relation, which varies witli the organism, seemed to exist between the 

 H-ion concentration of the medium and the accumulation of extra- and intra- 

 cellular amylase. 2. In Fusarium spec, maximum total accumulation was 

 produeed in the Solutions having an initial of pH 4,5 and a final reaction of 

 pH 7.8, whereas in Colletotrichum gossypii a culture Solution with an initial 

 of pH 7,0 and a final reaction of 7,9 afforded maximum results, but only 

 sUghtly less accumulation occurred at pH 8,2. Culture Solutions of pH 3,0 

 and pH 4,5 were equally favorable in the case of Penicillium italicum. 3. Amy- 

 lase accumulated more in the cultures of C. Gossypii than in the other fungi 

 studied. 4. A gradual decrease in the amylase accumulation was effected 

 by Fusarium sp. as the culture Solution became more alkaline, this decrease 

 not being coincident with a reduction in the amount of growth. 5. An increase 

 in accumulation occurred in the intra- and extracell ul ar amylase of C. gossypii 

 as the nutrient Solution became less acid, neutral or alkaline Solutions being 

 most effective. 6. The intra- and extraceUular amylase, produeed by any 

 one fungus under varying H-ion concentration of the culture Solution, had 

 similar properties with respect to the effect of the reaction of the NaOH- 

 HsPO^ buffer Solution lipon activation. 7. An optimum zone of activity, 

 between jjH 3,0 and pH 6,0, existed for P. italicum, while in the other fungi 

 the Optimum was more sharply defined at pH 6,0 when the activity was 

 measured in the buffer Solution, at 28" C for 24 hours. 8. Complete inactivation 

 occurred at pH 8,0 for the amylase of P. italicum. Under similar amounts 

 of amylase accumulation by Fusarium and C. gossypii, inactivation was effected 

 by Solutions of pH 9,0 to 11,0. 9. A decrease in the actual acidity of the culture 

 Solution occurred in cell of the series of P. italicum and all but the most alkaline, 

 or pH 9,2, series of Fusarium and C. gossypii. The former produeed no change 

 in the reaction of this culture Solution, while the latter caused a slight shift 

 toward neutrality. 



243. Kobel, F. Das Problem der Wirtswahl bei den para- 

 sitischen Pilzen. (Naturwiss. Wochenschi-. XXXVI, 1921, p. 113—118.) — 

 Nach der Ansicht des Verls, soll die Wirtswahl vor allem von der chemischen 

 Zusammensetzung der Eiweißstoffe der Wii'tspflanzen abhängen. Die Un- 

 regelmäßigkeiten in der WirtswahJ der Parasiten wird auf den Einfluß von 

 Reservestoffen, morphologischen Eigentümlichkeiten, vStoffwechselprodukten 

 und auf die in demselben Organismus vorkommenden verschiedenen Eiweiß - 

 Stoffe zurirekgeführt. 



244. Kobel, F. Das Problem der Wirtswahl bei den para- 

 sitischen Pilzen. (Mitt. Naturf. Ges. Bern 1920 [1921], p. XXXIII bis 

 XXXIV.) 



245. Kosin, N. L. Über aerobe Zersetzung von Zellulose durch 

 Schimmelpilze. (Nachr. d. Phys.-Chem. Lomonossow- Ges. Moskau II, 1921, 

 Nr. 1, p. 57 — ^98.) — Betrifft hauptsächlich Cladosporium. — Ref. in Zeitschr. 

 f. techn. Biol., N. F. d. Zeitschr, f. Gärungsphys. XI, 1924, p. 97. 



246. Kostytschew, S. Über Zuckerbildung aus Nichtzucker- 

 stoffen durch Schimmelpilze. (Zeitschr. f. physiolog. Chemie CXI, 1920, 

 p. 236 — ^245. ) — Werden Schimmelf>ilzkultiiren mit stickstoffreien Substanzen 



