Abstract
The studies of Hiss 1 show that inulin is fermented by the pneumococcus organism and that this fermentation can be used as a method of differential diagnosis between the Pneurnococcus group and the Streptococcus. Bergey 2 mentions a Streptococcus inulinaceus Orla-Jensen, which also ferments inulin. A differentiation between these two organisms can be made by using other sugars. Among fungi, the presence of an inulase appears to be widespread, and inulin decomposition has been observed both among higher and lower types. Bourguelot 3 found inulase in Aspergillus niger; Grüss 4 in Ustilago maydis; Dean 5 in Aspergillus niger and a Penicillium; Frou 6 in Morchella; Wehmer 7 in a species of Mucor; Hanzawa 8 in Rhizopus delemar; and Castellani and Taylor 9 in Monilia macedoniensis.
In view of the work of Harrison, Tarr and Hibbert 10 and of Hibbert, Tipson and Brauns 11 on the constitution of levan and its relation to inulin, it seemed of interest to investigate the fermentation reactions of levan obtained from B. mesentericus and from B. subtilis as well as of dextrans obtained from two different strains of Leuconostoc mesenteroides. ∗
The method used was as follows: Sugar-free bouillon plus 10% normal horse-serum and 1 % Andrades' indicator. The carbohydrate was added after filtration through a Berkefeld candle in order to make a final concentration of 1%. X control of the horse-serum, sugar-free broth, without carbohydrate, and each of the sugar media was seeded from an 18-hour blood-agar, slant culture of virulent “S” pneumococcus Types I and II, and also from an “R” pneumococcus of the same type. The cultures were incubated at 37°C. and reactivity observed after periods of 24 hours and 4 days respectively.
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