828 THE SLIME OF Df:MATIUM PULLrLASS, 



The gum-like substances were boiled with 5 % sulphuric acid 

 in flasks provided with aerial condensers for five hours. The 

 soluble portion was completely hydrolysed by the acid, as was 

 shown by the presence of reducing sugars and the absence of -a 

 precipitate upon adding alcohol to a small neutralised portion. 

 The water-insoluble gum had not been attacked, and the boiling 

 was continued for 20 hours. Still no reducing sugars could be 

 detected. From the resistance to hot dilute acid and from the 

 solubility in acid and alkali, it was probable that the slime would 

 eventually be shown to be a pararabin.* The hydrolysis with 

 concentrated acid was deferred. 



The acid in the solution of the hydrolysed v/ater-soluble portion 

 was removed by barium carbonate. Traces of the precipitate 

 that passed through the filter were eliminated with aluminium 

 hydrate and the clarified solution was evaporated to small volume. 

 Phenylhydrazine acetate solution was added, and the whole was 

 heated on the water-bath for two hours. The osazones that 

 separated out upon cooling the fluid were filtered off, moistened 

 with alcohol and extracted with ether, which removed much 

 impurity. The semi-pure osazones were heated with water, which 

 dissolved a trace of galactosazone and a vitreous yellow substance 

 comparatively easily soluble in hot water. The portion insoluble 

 in water was dissolved in hot alcohol and cooled. There separated 

 out a yellow crystalline precipitate which melted at 200° and 

 which was eventually separated into galactosazone (m.p. 193'") 

 and glucosazone (m.p. 205 '■''). The cold alcohol filtrate from the 

 osazoue (m.p. 200*^) upon evaporation yielded glucosazone. 



The soluble substance extracted from the cultures of Dematium 

 pullulans by dilute acid thus hydrolysed to galactose and a glucose. 



These results were confirmed by the examination of a fluid 

 culture. Much the same method of procedure was adopted in 



* It may be noted here that Skerst (Cent. f. Bakt. 2, iv., 864) found that 

 Dematium pullulans produced a characteristic skin of a gelatinous con- 

 sistency with sugars such as saccharose, dextrose and levulose, especially 

 when these were present in nutritive fluid to the extent of 10%. He found 

 that the slime or gum was not attacked by nitric and hydrochloric acids, zinc 

 chloriodide, iodine, alcohol, petroleum ether, ether, chloroform or potassium 

 hydrate. It was attacked by concentrated sulphuric acid. 



