摘要:

The influence of different extracts on the acid production of two strains ofStreptococcus cremorisand two ofBetacoccus cremorisisolated from Kingston cheese has been studied.The enriching entity has no effect on acid production byStreptococciin sugar broth. Enrichment with yeast or alfalfa extract causes not only a marked increase in the acid production byBetacocci, but also a definite stimulating effect on the rate of acid production.Enriching milk with yeast or alfalfa extract has a marked stimulating effect on the vital activity of theBetacocciand ofStreptococcusEMB1173, but is without influence onStreptococcusEMB1195. The response of culture EMB1173 is immediate and direct, but in the case of cultures EMB2168 and EMB2173 the action of the enriching entity is cumulative in its effect. Alfalfa extract would appear to provide, in the case ofBetacoccusEMB2173, a stimulating influence not to be found in yeast extract.The influence of other forage crop enrichments on rate of acid production has also been studied. The factor or factors present in alfalfa and shown to exert a stimulating influence on the vital activity of the organisms are to be found to some extent in all forage crops investigated.

ISSN:1923-4287    

DOI:10.1139/cjr36b-019

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

The influence of the Bios of Wildiers on the vital activity of two strains ofBetacoccus cremorishas been studied. Alfalfa, yeast and tomatoes have been fractionated after the manner of Miller, and the effect of the respective Bios fractions on acid production determined. It has been shown that theBetacoccidemand, for their most intensive metabolism, activators corresponding to those required by yeasts—Bios I, IIAand IIB.

ISSN:1923-4287    

DOI:10.1139/cjr36b-020

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

The lipid composition of the guinea pig placenta was found to vary with the duration of pregnancy. Between the 20th and the 40th days there occurred an increase in phospholipid and free cholesterol, both of which remained elevated from then on to term. There was no significant change at any time in the amount of cholesterol esters, but that of neutral fat increased steadily sixfold and more during pregnancy. These changes were interpreted as signifying a gradual change in placental lipid metabolism during pregnancy. The relation of this change to the transfer of lipids from mother to fetus, and its relation to the etiology of the lipemia of pregnancy in guinea pigs, are discussed.

ISSN:1923-4287    

DOI:10.1139/cjr36b-021

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

A number of recent methods for the estimation of bromine in plant and animal tissues have been tested. A combination of the methods of Francis and Harvey (34) and of Yates (98), with some modifications, has been proved capable of yielding controlled and accurate results for amounts of bromine not less than 3 micrograms, in amounts of material of not more than 1 gm.Using the method outlined, material from a large number of marine plants and animals and from typical land plants and animals has been examined for bromine content; in many cases iodine analyses were either already available or have been made on the same material. The results suggest the following conclusions:Bromine is an invariable constituent of marine algae, but no definite relation appears to exist between their bromine and iodine contents. Land plants contain considerably less bromine. Environmental conditions, and perhaps selective affinity by the species and cells in the different parts of the individual plant, probably determine the actual content of bromine.All the marine species of animals examined contain bromine; but in very variable quantity. Environment and selective cell affinity appear to be the controlling factors.The thyroid and blood of the mammals completely examined (rat, rabbit, and dog) contain amounts of bromine slightly higher than those present in other tissues. Ox, sheep and hog thyroids contain similar amounts. Pituitary tissue contains amounts scarcely, if at all, greater than most of the other tissues of the mammalian organism; this last finding is not in agreement with statements by certain other investigators.No relation has been found to exist between the distribution of bromine and iodine in mammalian tissues, and, so far, it is uncertain whether bromine is of functional significance, especially since it does not appear to be particularly associated with the thyroglobulin of the thyroid.

ISSN:1923-4287    

DOI:10.1139/cjr36b-022

出版商:NRC Research Press    

年代:1936

数据来源: NRC