摘要:

The influence of yeast extract on the bacterial flora of commercial cheese starters has been studied.The addition of yeast extract to the starter milk appears to favor the development of a larger proportion of slow acid-producing strains of streptococci with the ability to ferment the more complex carbon sources.New strains of lactic acid streptococci are described.

ISSN:1923-4287    

DOI:10.1139/cjr36b-035

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

The influence of the configurational relations of the hexoses on the ability of aStreptococcus cremorisstrain to produce acid from lactose in milk and in broth has been studied.With casein digest broth as the nitrogen source, the organism was carried by serial transfers in 10 different carbon sources; at every transfer the cultures were inoculated from the sugar broths into milk, and the clotting times of the respective milk tubes determined.The carrying of the culture in sucrose, maltose, dextrin or starch has no influence on the acid-producing ability of the organism.Glucose, mannose, fructose, and salicin exhibit a marked inhibiting effect on the rate and amount of acid production in milk and in lactose broth.Although galactose and lactose fail to inhibit completely the activity of the organism, a restraining influence on acid production is to be observed. It is suggested that the inhibitory activity of glucose or one of its metabolic products may be a cause of the sudden or gradual loss of vitality in starters.

ISSN:1923-4287    

DOI:10.1139/cjr36b-036

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

A new alkaloid,corlumine, has been isolated fromCorydalis scouleri,C.sibiricaandDicentra cucullaria. Chemical examination disclosed its isomerism with adlumine with which, furthermore, it is structurally identical. It differs from the latter only in the disposition of the substituents about the two asymmetric C-atoms, but it is not the optical antipode of adlumine.Corlumidineis O-desmethyl corlumine and has been found only inC.scouleri, and on methylation with diazomethane yields corlumine. The free hydroxy-group is probably present in the 7-position of the isoquinoline nucleus.

ISSN:1923-4287    

DOI:10.1139/cjr36b-037

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

The reaction aluminium oxide–carbon–chlorine has been investigated and found to produce aluminium chloride, oxygen and carbon dioxide. This occurred when a mixture of aluminium oxide and carbon was heated either in a stream of chlorine or in a static atmosphere of chlorine. No carbon monoxide was obtained when a stream of chlorine was used, but small amounts were formed in a static atmosphere of chlorine. The temperature at which reaction started, as shown by the formation of a sublimate of aluminium chloride in the reaction tube, decreased as the proportion of carbon to aluminium oxide increased. In a number of experiments, less carbon was consumed than should have been for the amount of aluminium oxide that reacted, if it be assumed that carbon dioxide, rather than oxygen, was a primary product. From the results obtained, the writers believe that oxygen is a primary product of the reaction, while carbon dioxide is a secondary product, the carbon acting primarily as a catalyst.In experiments with tungstic oxide, also, oxygen was produced, but, contrary to the findings of other investigators, carbon dioxide was also formed.

ISSN:1923-4287    

DOI:10.1139/cjr36b-038

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

Delignification rates of spruce wood chips and wood-meal have been investigated under carefully controlled conditions at temperatures ranging from 100° to 140 °C. The rates are shown to be in only approximate agreement with the monomolecular law, but the change in the rate of delignification with temperature obeys the equation of Arrhenius.

ISSN:1923-4287    

DOI:10.1139/cjr36b-039

出版商:NRC Research Press    

年代:1936

数据来源: NRC