(591 Fermeuto und Enzyme. 425 



oder zu hohe Acidität) die Oxydasereaktion gehemmt wird. — Zum Nachweis 

 der Chromogene muss man ihre Oxydation durch das Enzym im Augenblick, 

 wo das pflanzliche Gewebe zerrieben wird, verhindern. Zu diesem Zweck 

 arbeitet man am besten mit verdünnter HjSO«. Quantitativ lässt sich die 

 wirksame Substanz aus dem zeitlichen Ablauf der Jodreaktion schätzen. Bei 

 Artischocken, Salaten, Weissdornblättern. Ivirsch-, Pflaumen- und Vogelbeer- 

 baum tritt die Reaktion sofort ein, sie bleibt negativ bei den Blättern der 

 Eiche, der Iris, der Akazie, des Mohns und beim Mycel von Aspergillus niger. 

 In reiner Form konnten die Chromogene bisher nicht isoliert werden (Lewiu 

 in Centrbl. ßiochem. Biophysik XVIII, 1915, p. 442). 



735. Zeller, Saiiford IVI. Studies in the physiology of the fungi. 

 IL Lenzites saepiaria Fries, with special reference to enzyme act- 

 ivity. (Ann. Missouri Bot. Card. III, 1916, p. 439-509, mit 2 Taf.) - Die 

 Zusammenfassung lautet: In this paper there are considered some of the 

 more important aspects of the physiology of a wood-destroying organism, 

 Lenzites saepiaria. 1. The fungus was grown in pure cultures, and the characte- 

 ristics of the mycelium and sporophores produced under cultural conditions 

 are described. 2. Some factors influencing the growth and metabolism of the 

 organism are discussed. and experimental results are given on the relations 

 of the fungus to reaction of media, to water, and to oxygen. Special interest 

 is attached to the influence of the resin. content of the substratum on the 

 gTOwth of the fungus. A resin agar emulsion was prepared. and experimental 

 data show that L. saepiaria will grow well on 50 per cent resin by weight, 

 whioh is considerably more than is found in any coniferous wood. Growth 

 is not entirely inhibited by 85 per cent resin. 3. The metabolism of the fungus 

 studied through the agency of enzyme action. a) A Standard method of 

 extracting and isolating the enzymes was used. and enzyme preparations were 

 made from vegetative and fruiting tissiies. The methods commonly used 

 of identifying the enzymes were employed. b) Among the esterases, those 

 acting on the esters of the lower fatty acids showed more active hydrolysis 

 both in sporophoral and mycelial tissues than those acting on the neutral 

 fats. c) In the carbohy drases, positive evidence was obtained of the presence 

 of maltase, invertase, raffinase, emulsin, tannase, diastase, 

 iuulinase, ligninase, cellulase, hemicellulase, and i>ectinase, 

 while negative results were obtained for the presence of pectase and lactase. 

 d) The cyto-hydrolyzing carbohydrases were made a special study 

 together with their effects as deinonstrated by microchemical observations on 

 sound and decayed wood. e) The action of amidase on asparagin and acet- 

 amid was practically negligible, while uiease action was very decided when 

 the fungous tissue was used instead of the enzyme preparations. The presence 

 of hipperricase was also demonstrated. f) The following additional enzymes 

 have also been found: nuclease, proteinases — both tryptie and ereptic — 

 rennetase, oxidase, and catalase. 4. A comparative study of the enzymes 

 occurring in the sporophoral and mycelial tissues was made. As we would 

 anticipate, this comparison shows that the important metabolic processes 

 are carried on in the vegetative organs. Indeed, wherever quantitative results 

 were obtained, or where a comparison can be accurately made, as in the case 

 of diastase, invertase, tannase, and cellulase, the greater activity 

 is shown in the mycelium. An exception to this, however. is the oxidases, 

 where the greater activity is in the sporophores. 



