Fat Solvents Research Articles

Preparation of Œstrin

RECENT work from several laboratories strongly suggests that the œstrus-producing hormone is a substance possessing weakly acidic properties. If this is so, the methods in general use for the preparation and purification of the hormone, involving as they donumerous extractions with fat solvents from neutral or alkaline aqueous media, must result in great losses of the active material. This is borne out by the observation of Miss M. Hill, privately communicated to me, that urine extracted as many as twelve times with ether may still contain large amounts of œstrin.

Resistance of Causative Agent of Chicken Tumor to Certain Organic Solvents Compared with Vaccine Virus and Herpes Febrilis Virus.

SummaryThe causative agent of Chicken Tumor I resists freezing and desiccation, and this dried material retains its activity after king shaken for 6 days in dry acetone, alcohol, and toluene. The same is true of vaccine virus. The dried material of Chicken Tumor I is rendered inactive by shaking with chloroform while vaccine virus in the dried state withstands such treatment. Herpes febrilis in brain tissue resists freezing natl desiccation but is destroyed when the dried material containing it is shaken with alcohol, acetone, toluene, or chloroform. None of the agents studied are extracted in their active form from the dried material by the solvents.From these results it would appear to be impossible to distinguish between the agent of Chicken Tumor I anti viruses by desiccation and subsequent treatment with the ordinary organic fat solvents.

ENLARGEMENT OF THE ADRENAL CORTEX IN EXPERIMENTAL UREMIA

The production of an experimental uremia in the albino rat by removal of both kidneys is followed by hypertrophy of the adrenal glands. In the case of male rats 90 days of age this adrenal enlargement amounted to 65 per cent and in the case of female rats 180 days of age 47 per cent. The increase in the size of the whole gland is due entirely to hypertrophy of the cortex. This increase in the volume of cortical tissue amounted to approximately 40 per cent for males and 61 per cent for females and was due in large part to an increase in the size of the cells. The content of water and material soluble in fat solvents was higher in the uremic than the control glands. However after subtraction of such storage materials a true hypertrophy of the cortex still remained. It amounted to 21 per cent. Histologically the stainable fat had a more irregular distribution and was present in lesser amount in the adrenals from the uremic animals. The capillaries of the medulla and reticular cortex were distended. The nuclei of both the cortical and medullary cells were swollen and stained faintly.

The elimination of certain dyes from the animal organism.

The observations of Delprat and others1 that an aqueous solution of rose bengal when injected intravenously into animals is rapidly eliminated through the bile, is not without theoretical significance as well as of practical value. Its behavior in this respect is wholly like that of the bile acids.2 Rose bengal is not soluble in the ordinary fat solvents and its behavior in the body does not follow the assumption of Mendel and Daniels3 that substances which are eliminated from the body by way of the bile must be insoluble in water and soluble in bile or substances contained therein.Rose bengal is a highly diffusible substance and it was not found possible to retain it within an ordinary collodion membrane. This property suggested that it might be possible by ligation of the bile duct to force the dye through the kidney. Numerous experiments∗ which were carried out on both dogs and rabbits showed that after ligation of the bile duct, rose bengal was found present in the blood stream for a period of 48 hour...

The requirements of the pig for “vitamin A” and “vitamin C.”

Most of our information on the subject of vitamins has been derived from experiments on small animals fed on synthetic diets. The direct application of the results of such experiments to the feeding of farm animals under practical conditions is not warranted. Animals differ in the degree of their susceptibility to disease caused by lack of vitamins, and laboratory diets, composed of foodstuffs subject to abnormal physical or chemical processes, such as heating under pressure, or prolonged extraction with fat solvents, have no parallel in animal husbandry.

A test for peristaltic activity

The agent used is the red dye known as Sudan III. Its advantages are that it may be used in very small amount thus interfering very little, or not at all, with the normal processes in the alimentary tract. The amount used for man is from 50 to 70 milligrams (3/4 to 1 grain). It is soluble only in a fatty medium or in fat solvents. Taken with, or just after a meal, it is not impossible that a slight amount may be combined with the fat of the meal and absorbed to a slight extent; otherwise it is not, apparently, susceptible to the alimentary secretions. The tests have not been interfered with by any absorption that may have occurred. The red color of the dye is essential for the test. The rapidity with which the dye, mixed with the ingesta, will pass through the intestinal tract will depend upon peristaltic activity, the secretions, the frequency of evacuations and the amount of material ahead of it. In constipation the time will be lengthened and in diarrhea it will be shortened. The test consists in giving 50-70 miligrams (3/4 to 1 grain) of Sudan III in a gelatin capsule, just before, or after, a meal. One or two grams of the feces from the subsequent evacuations are taken and dried. A record should be kept of the time of administration of the dye and of the evacuations which follow. After drying, the material is extracted with ether. The extract from the first feces passed (before the dye appears) is used as a control. Its color is usually greenish yellow or light brown. Later evacuations, depending on conditions, begin to show a red color.

Outline of a classification of the lipoids

At the meeting of the American Society of Biological Chemists in December, 1919, the matter of a classification of the fats and related substances was brought before the members for discussion. It was decided that the available knowledge on the subject was insufficient to justify a classification at that time. While admitting the truth of the conclusion it has seemed to me since, that something might be gained by an attempt at classification,—in clarifying our ideas and in bringing the newer developments in the field into connection with the old—even though the scheme might later have to be radically changed or even abandoned. It is becoming more and more apparent, for example, that the fats and the substances ordinarily grouped under the name of lipoids are so intimately related both chemically and in metabolism—all being directly connected with the metabolism of the fatty acids—that they should be considered together, and when so considered they form a group which is believed to be as distinct and well defined as that of the carbohydrates and proteins. The following is an outline of proposed classification: The higher fatty acids, their naturally occurring compounds and certain substances found naturally in chemical association with them. The group is characterized in general by insolubility in water and solubility in‘ fat solvents‘-ether, chloroform, benzol, etc. Fats.-Esters of the fatty acids with glycerol. (fats which are liquid at ordinary temperatures are called oils.) Waxes.-Esters of the fatty acids with alcohols other than glycerol. Beeswax, lanolin, cholesterol oleate. GlycoZipoids.-Compounds of the Fatty acids with a carbohydrate and nitrogen but containing no phosphoric acid.-Cerebron, etc.

STUDIES ON BIOLUMINESCENCE

STUDIES ON BIOLUMINESCENCE

The Antigenic Properties of Tubercle Wax

Abstract Tubercle wax is the name applied to fatty and waxy substances extracted from tubercle bacilli with fat solvents such as alcohol, ether, benzol, chloroform, etc. Historical and Nature of Tubercle Wax. Hammerschlag was first to show that tubercle bacilli contained a large amount of fatty and waxy substances, and that in this respect they differ from other vegetable microörganisms. De Schweinitz and Dorset confirmed Hammerschlag's results, and since then a great deal of attention has been paid to this subject. All investigators agree that it is difficult to extract the fatty substances entirely, and that the amount is influenced by the culture media upon which the bacilli are grown and by other factors mentioned below. Proskauer and Beck have demonstrated that bacilli cultivated on fat free media are also able to produce wax, although in smaller amount (10 per cent of dried bacillary substance).