FOODS HUMAN NUTRITION.

Nutritive factors in animal tissues, I, T. B. OSBORNE, L. B. MENDEL, ET AL. (Jour. Biol. Chem., 32 (1917), No. 3, pp. 309–323, figs. 5).—The products of animal and vegetable origin which have been found to contain either the fatsoluble or water-soluble vitamin have been tabulated with references to the original literature, and the results of further investigations as to the occurrence of the water-soluble factor in certain animal products are reported. Beef muscle, meat extract, the tissue residue from this meat extract, and dried pig liver were investigated by the authors, following the plan of their earlier studies with rats.

The results of the nutrition experiments show that both the meat powder and the meat residue seem to be deficient in the water-soluble food hormone, although both are suitable as sources of protein in the diet when the other essential ingredients are present in sufficient amounts. The meat extract was found to contain at least a small amount, and the dried pig liver a large amount, of the water-soluble vitamin as well as adequate protein.

It is pointed out that the results parallel the findings of Cooper (E. S. R., 31, p. 762) in respect to the relative antineuritic properties of muscle and liver, and agree with those of Eddy (E. S. R., 36, p. 160) on the growth-promoting properties of the water-soluble extract of the pancreas. The adequacy of both the meat powder and the meat residue as sources of protein is emphasized in view of the fact that meat residues after the preparation of soups from muscle tissue are often discarded as inferior food products.

Nutritive factors in plant tissues.-I, The protein factor in the seeds of cereals, T. B. OSBORNE, L. B. MENDEL, ET AL. (Jour. Biol. Chem., 34 (1918), No. 3, pp. 521–535, fig. 1; abs. in Chem. Abs., 12 (1918), No. 16, p. 1657; Jour. Soc. Chem. Indus., 37 (1918), No. 17, p. 526 A).-The authors point out that in feeding experiments no adequate comparison between the value of different proteins can be made unless the quantity of protein actually eaten is known. To determine the relative value of the total protein in some of the commonly used cereals, feeding experiments were conducted with rats, the protein of the diet being supplied by protein concentrates from the cereal under investigation prepared by removing the starch by the action of diastase. Concentrates of rice, barley, corn, and wheat were tested.

The preliminary results which are reported offer evidence that "the total proteins of rice and barley, in contrast with maize and oats, when furnished in diets containing 16 to 17 per cent of protein, supply enough of all the amino acids essential for growth." It is stated, however, that the experiments reported indicate that it ought to be possible to make an animal grow on a diet in which the maize kernel is the sole source of protein, provided a preparation of the total proteins could be obtained which would permit feeding them in sufficient quantity so that enough of those amino acids which are present in certain of the proteins and not in others would be available to meet the minimum nutritive requirements of the organism.

It was found that the amino acid deficiencies of the protein concentrate of oats could be supplemented by casein or gelatin, the former proving the more satisfactory.

A biological analysis of pellagra-producing diets.-II, The minimum requirements of the two unidentified dietary factors for maintenance as contrasted with growth, E. V. MCCOLLUM and NINA SIMMONDS (Jour. Biol. Chem., 32 (1917), No. 2, pp. 181-193, pls. 3, figs. 3).-Continuing the study of pellagraproducing diet (E. S. R., 39, p. 266), the authors report the results of a series of experiments designed to show the magnitude of the interval between the require

ments of young rats for fat-soluble A and water-soluble B for maintenance, as contrasted with growth, and also a series of tests with full-grown rats for the purpose of comparing the maintenance requirement of adult with that of young tissues. From the experimental data the following conclusions are drawn:

There is no low plane of intake of either fat-soluble A or water-soluble B which can be said to maintain an animal without loss of vitality. More than the minimal amount necessary for the prevention of loss in weight must be used if the diet is continued for any length of time. Within certain limits growth is proportional to the supply of both factors, all other factors being properly adjusted. A low intake of either factor can be tolerated much better with an otherwise excellent diet than with one which is less well constituted. An attempt to fast an individual selectively for one or both of these dietary essentials is a dangerous procedure.

The authors assert that efforts directed toward the control of tumor growth by eliminating growth factors from the diet can never become of practical value, as the life of the host will be cut short if the experimental conditions imposed are sufficiently rigid to render growth impossible.

A biological analysis of pellagra-producing diets.—III, The values of some seed proteins for maintenance, E. V. MCCOLLUM and NINA SIMMONDS (Jour. Biol. Chem., 32 (1917), No. 3, pp. 347–368, figs. 13).—Continuing the above inves tigation, the authors have studied the relative value of the total protein of certain seeds by means of biological studies with rats, using a diet adequate in respect to every factor except protein, which was supplied by the seed under investigation. In one case a pure carbohydrate was added to produce a low protein mixture, in another the mixture was fed without any carbohydrate addition, and in a third the mixture was fed with a protein preparation from the seed employed so as to raise the protein level.

It was found in all cases that the vitality of the animals was greatly lowered by a diet otherwise adequate but near the physiological minimum in its protein content. From single seeds the plane of protein intake necessary for maintenance of body weight in grown or nearly grown rats when all other dietary factors were properly adjusted was found to vary from 4 to 6 per cent in the case of millet, oat, wheat, maize, rice, flax, and cotton seeds to about 11 per cent in the navy bean and pea. Millet seed and oat seed proteins appeared to be better than the other seed proteins. The nitrogen of the alfalfa leaf when fed as the sole source of protein showed no superiority over the seed proteins.

In the application of this data to the interpretation of the dietary factors operating to produce pellagra the authors call attention to the diet employed by Goldberger and Wheeler (E. S. R., 34, p. 258) for the production of experimental pellagra in which the protein consumption was not far from 8 per cent of the food mixture. This protein, derived almost wholly from seeds, is considered too low to support normal growth and close to the point where the resistant power of the adult will be decreased.

In conclusion the authors state that "there is in reality no quantity of protein, fat-soluble A, or other constituent of the diet which can be designated as the physiological minimum, without the biological values of every other dietary factor being also stated. The least amount of butter fat which will suffice to support growth when the diet is otherwise of good constitution will not be adequate in another case in which the quality of one or another factor is of a low order. This idea should be kept clearly in mind in interpreting the etiology of pellagra, in cases where several dietary factors fall below the optimum."

The dietary qualities of barley, H. STEENBOCK, HAZEL E. KENT, and E. G. GROSS (Jour. Biol. Chem., 35 (1918), No. 1, pp. 61–74, figs. 20; abs. in Chem.

Abs., 12 (1918), No. 19, p. 2000).—The dietary qualities of barley were studied by means of feeding experiments with rats.

It was found that barley alone is unable to meet the demand of the growing animal. It is deficient in inorganic salts and in the fat-soluble vitamin but contains an abundance of the water-soluble vitamin. The protein content (13.6 per cent) proved to be too low for continued growth at the normal rate. The authors conclude that "the primary growth determinant in barley is inorganic salts. Of secondary importance, but no less urgent, are protein and fat-soluble vitamin."

The use of soy bean as food, T. B. OSBORNE, L. B. Mendel, et al. (Jour. Biol. Chem., 32 (1917), No. 3, pp. 369–387, figs. 5).-The authors have studied the nutritive possibilities of various soy bean products, using white rats as the experimental animals. Variations in the apparent nutritive value of raw and cooked soy bean meal indicate that there is nothing toxic in the raw meal, but that cooking the meal tends to make it more palatable. The different results obtained with the commercial soy bean flours are likewise attributed to unlike methods of heating in their preparation. The properly cooked soy bean was found to contain proteins adequate for promoting normal growth, an adequate supply of the water-soluble vitamin, and some of the fat-soluble vitamin. It is deficient in its mineral constituents, being relatively poor in calcium and chlorin. The authors consider that the facts that the soy bean is the only seed hitherto Investigated, with the possible exception of flax and millet, which contains both the water-soluble and fat-soluble vitamins and that its protein is of high physiological value lend a unique significance to its use as a food.

The value of the yeast vitamin fraction as a supplement to a rice diet, A. D. EMMETT and L. H. McKIM (Jour. Biol. Chem., 32 (1917), No. 3, pp. 409-419, Ags. 4). This is a report of the first of a series of investigations dealing with the efficiency of the vitamins from autolyzed brewers' yeast as adjuvants to a diet that has been shown to be deficient in some particular vitamin. Pigeons were fed on polished rice until polyneurits developed. They were then treated with the Seidell autolyzed yeast vitamin and after recovery were fed a diet consisting of one of the following: Polished rice with vitamin, shelled corn, brown or natural rice, brown rice with vitamin, barley, unhulled oats, and hulled oats.

A study of the different reagents used to adsorb the vitamin fraction from autolyzed yeast led to the conclusion that ordinary fullers' earth ground to a definite fineness is as satisfactory as Lloyd's reagent, but that the kieselguhrs do not adsorb the yeast vitamin. The effect of the dietary treatments and the authors' conclusions are summarized as follows:

"The activated fullers' earth when given as a rational supplement to a polished or a brown rice diet acts as a partial stimulant to increase the weight of the treated polyneuritic pigeons. It does not, however, in the case of the polished rice, accelerate the increase in weight to anything like that which is produced under similar conditions with brown rice alone, corn, barley, or hulled oats, and, comparatively speaking, this activated yeast vitamin is not a complete supplement to a polished rice diet.

"There are apparently two so-called vitamins associated with rice polishing, one which cures polyneuritis and one which produces weight, and of these two, the Seidell yeast vitamin preparation contains chiefly the curative fraction along with a small percentage of the other.

"Finally, it is evident that while this activated yeast vitamin product is a valuable adjuvant to the diet in the case of convalescents from avian polyneuritis, yet, for the best results, the diet should, in addition, be made up in part at least of vitamin-containing foods, not for the purpose of preventing the

recurrence of typical attacks of this dietary deficiency disease (for the preparation is able to do this) but with the object of bringing about normal gains in weight and complete recovery."

Food accessory factors (vitamins) in bacterial culture, with especial reference to hemophilic bacilli, I, D. J. DAVIS (Jour. Infect. Diseases, 21 (1917), No. 4, pp. 392–403; abs. in Abs. Bact., 2 (1918), No. 2, p. 59).-The author discusses the following characteristics of hemoglobin in relation to the growth of hemophilic bacteria: (1) Hemoglobin is essential for their growth, (2) it is sufficient in high dilution, (3) alone it will not support growth, other proteins being necessary for continued development, and (4) it does not lose its power of supporting growth through prolonged heating at the boiling point or even higher. Attention is called to the close correspondence between these characteristics and the properties and mode of action of the food accessory factor, watersoluble B. The fact that a much greater growth of hemophilic bacteria takes place when fresh animal or plant tissue is added to the medium or another organism is allowed to grow on the same plate suggests the similarity of the tissue factor to fat-soluble A.

The author concludes that the activity of the food accessory substances in animals and in higher plants may concern, or in some way control, the metab olism of certain elements like iron, phosphorus, calcium, or iodin, as well as, possibly, the protein metabolism.

Food accessory factors (vitamins) in bacterial culture, II, D. J. Davis (Jour. Infect. Diseases, 23 (1918), No. 3, pp. 248-251).-The study noted above has been extended to include the problem of finding substances which might enhance the growth of other than hemophilic bacteria. The organisms used were Bacillus coli, B. typhosus, B. diphtheria, Streptococcus hemolyticus, Staphylococcus aureus, Blastomycetes, Sporotrichum schenckii, Streptothrix, B. pyocyaneus, and B. prodigiosus.

It was found that these organisms are not apparently specifically stimulated to grow through the addition to ordinary media of hemoglobin or of vitamincontaining substances such as unpolished rice and wheat bran. The addition of sprouted grain to the medium caused a much more rapid growth. The author suggests as factors responsible for the growth stimulation soluble vitamins, sugars, and more soluble nitrogenous products produced in the sprouting process.

Horse flesh as human food, L. PRICE (Jour. Amer. Vet. Med. Assoc., 51 (1917), No. 5, pp. 679-692).-This article includes an historical outline of the use of horse flesh as a human food; a description of the dressed carcass of the horse, with a summary of analytical data as to its composition; a discussion of meat inspection, including the pathological conditions met with in the slaughtering of horses; a criticism of arguments advanced in opposition to the use of horse flesh as food; a description of the restrictions and means of control of the sale of horse meat; and tests for its detection.

The casein of human milk, A. W. BOSWORTH and LOUISE A. GIBLIN (Jour. Biol. Chem., 35 (1918), No. 1, pp. 115-117; abs. in Chem. Abs., 12 (1918), No. 19. pp. 1971, 1972).-Casein isolated from human milk was found to contain 5.31 per cent moisture and to give the following results on analysis calculated to the dry basis: Nitrogen 15.75 per cent, phosphorus 0.7, and sulphur 0.7. These results correspond closely to those of goat's and cow's milk, previously noted (E. S. R., 34, p. 708). The casein also resembles that of goat's and cow's milk in valence, molecular weight, and in reactions with bases and with rennin.

The metabolism of the mustard oils, W. H. PETERSON (Jour. Biol. Chem., 34 (1918), No. 3, pp. 583–600, figs. 4; abs. in Chem. Abs., 12 (1918), No. 16, p. 1657).—

Metabolism experiments with pigs for the purpose of throwing some light on the chemical changes the mustard oils undergo in the body are reported.

Evidence is given of a very slow metabolism of the oils and of the inability of the body to dispose of these oils readily. Although not oxidized in their passage through the animal, they are not eliminated unchanged, as there is little or no mustard oil in the urine. It is possible that they are converted into some nonvolatile, less toxic substance. The fact that there is no particular increase in the volatile or total sulphur in the feces shows that the oils are absorbed from the digestive tract. From 40 to 70 per cent of the oil appears to be excreted in the urine, the remainder probably being eliminated through the lungs and skin.

Amylase and protease action of some pancreas preparations, H. C. SHERMAN and DORA E. Neun (Proc. Soc. Expt. Biol. and Med., 15 (1918), No. 4, p. 55).— The authors have shown that purified preparations of pancreatic amylase always exhibit a marked proteolytic activity, whether tested by the determination of total and of amino nitrogen, by determination of the acidity of digestion, or by the increase of electrical conductivity.

Action of pancreatic enzyms upon casein, H. C. SHERMAN and DORA E. NEUN (Jour. Amer. Chem. Soc., 40 (1918), No. 7, pp. 1138–1145; abs. in Chem. Abs., 12 (1918), No. 17, p. 1786).—Continuing the investigations noted above, the authors report a comparative study of the hydrolysis of casein by various preparations derived from the pancreas. Analytical data are given of the proteolytic activities of high-grade commercial pancreatins, of the three principal fractions recovered from the pancreatin in making from it the pancreatic amylase preparations, and of the most active trypsin commercially available. The followIng results were obtained:

"Extraction of the pancreatin, with 50 per cent alcohol, leaves a residue having about the same proteolytic activity as the original pancreatin. The sac precipitate obtained during dialysis in 50 per cent alcohol in the course of purification of pancreatic amylase had 15 times the proteolytic activity of the original high-grade pancreatin and about 4 times that of the most active commercial trypsin which we have seen. The final preparation of pancreatic amylase purified as described in previous papers from this laboratory has proteolytic activity fully equal to that of the high-grade trypsin when tested by any of the five methods used for the measurement of proteolytic power."

[Analysis of a so-called egg substitute], E. F. LADD and ALMA K. JOHNSON (North Dakota Sta. Spec. Bul., 5 (1918), No. 4, pp. 87-89).-An analysis of the product called "Sa-van-eg," a so-called egg substitute, showed it to be composed mainly of yellow corn meal, with some milk powder and a little baking soda.

[Miscellaneous food and drug topics], E. F. LADD and ALMA K. JOHNSON (North Dakota Sta. Spec. Bul., 5 (1918), No. 4, pp. 75-90).—In addition to several articles abstracted elsewhere in this issue, this number contains an article by F. W. Christensen, entitled "Shall We Eat Whole-wheat Bread?" an analysis of a proprietary drug preparation, and data as to the composition of various foods and beverages analyzed.

Coriaria myrtifolia as an adulterant of marjoram, G. M. BERINGER (Amer. Jour. Pharm., 90 (1918), No. 8, pp. 555–565, figs. 11).—Various methods employed In the detection of C. myrtifolia as an adulterant of marjoram are discussed, and a microscopical study is reported of the structure of marjoram and of authentic samples of the leaves of C. myrtifolia.

Food Surveys (U. S. Dept. Agr., Food Surveys, 1 (1918), Nos. 12, pp. 16, figs. 21; 13, pp. 16, figs. 19; 14, pp. 16, figs. 24; 2 (1918), No. 1, pp. 8).—The first of these four numbers presents data as to the commercial stocks of beans, peas,