# STUDIES IN NUTRITION

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## STUDIES IN NUTRITION

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## Nội dung Text: STUDIES IN NUTRITION

1. STUDIES IN NUTRITION. IV. THE UTILIZATION OF THE PROTEINS OF THE LEGUMES. BY LAFAYETTE B. MENDEL AND MORRIS 5. FINE. (From the Shejield Laboratory of Physiological Chemistry, Yale University, New Haven, Connecticut.) Downloaded from www.jbc.org by guest, on January 21, 2010 (Received for publication, September 25, 1911.) CONTENTS. Earlier studies. ................ ........ ........ ....... 433 Experimental part ............. ........ ........ ....... 435 Products employed ........ ........ ........ ....... 435 Metabolism experiments. ... ........ ........ ....... 437 Soybean ............... . .. . .. . . . .. . . . .. . .. . 437 White bean ............ ........ ........ ....... 446 Crude bean protein. .... ........ ........ ....... 448 Phaseolin ............. ........ ........ ....... 454 Pea globulin. .......... ........ ........ ....... 454 Nitrogen balances .......... . .. .. . . .. . . ....... 456 Summary. ...................... . .. . .. . 457 EARLIER STUDIES. The literature on this subject has been so adequately reviewed by Wait, that only the most cursory consideration of the earlier work need find place here. In experiments on a man, Hoffmann found the nitrogen of a diet of lentils, bread and potatoes to be 53 per cent available, against a utilization of 82 per cent for the nitrogen of meat. Woroschiloff compared the utilization of the protein of peas with that of meat protein. In three cases the meat protein was 90, 92, and 96 per cent utilized against 83, 88, and 90 per cent for the digestibility of the protein of the peas. Strtimpell found the nitrogenous constituents of “leguminose”-a finely ground commercial preparation, consisting of a mixture of lentils, peas and rye-to be 90 per cent available, against a utilization of 433
2. 434 Utilization of Legume Proteins but 60 per cent in an experiment with unground lentils. Rubner has pointed out that in the experiments of both Woroschiloff and Strtimpell, materials other than legumes were eaten, and these accessories may have exerted a favorable influence. Accordingly, Rubner conducted two experiments with thoroughly cooked hulled peas which were the only food consumed. The utilization was 72 to 83 per cent. In Malfatti’s experiments, peas were 86 per cent utilized and Potthast found lentils to be 74 per cent digested. In an experiment by Prausnitz, white beans, soaked for several hours and then cooked till soft, yielded 70 per cent available nitrogen. Erismann found the nitrogen of peas to be 80 per cent Downloaded from www.jbc.org by guest, on January 21, 2010 digested. Richter obtained a utilization of 90 per cent for the nitrogen of peas cooked in distilled water, against 83 per cent when hard water was employed in the process of cooking. Under the latter condition particles of apparently unchanged peas were ob- served in the feces. The poor digestibility of the peas cooked in hard water is attributed in part to the formation of difficultly digestible alkali earth albuminates, and in part to the digestive disturbance due to the magnesium salts in the water. Snyder reported a utilization of 80 per cent for the protein of peas, and obtained a similar result with beans. In their experiments with the Maine lumbermen, Woods and Mansfield estimated the pro- tein of beans to be at least 78 per cent utilizable, and an average digestibility of 65 per cent is reported in Oshima’s compilation of Japanese investigations. In a very thorough study, Wintgen found the average coefficients of digestibility of lentils, beans, and peas to be 78, 80 and 86 per cent respectively. Wintgen’s results are in accord with those obtained in an extensive investigation by Wait, in which a utilization of 77 to 78 per cent was obtained for bean protein, and 70 to 83 per cent for cow pea protein. In commenting upon this literature one can but reiterate the statements made in a previous paper’ of this series, and point out the necessity for studying the utilization of the isolated protein, or material in which the protein is more readily accessible to the digestive juices. 1 Mendel and Fine: This Journal, x, p. 303, 1911.
3. Lafayette B. Mendel and Morris S. Fine 435 EXPERIMENTAL PART. Products Employed. 1. SOY BEAN.' This material was an impalpable yellow pow- der, which betrayed no cellular structure under the microscope. In respect to consistency, it would thus appear to be ideal for digestion experiments. As may be observed from the accompany- ing analysis,2 the soy bean offers several points of interest: per cant Protein ....................... . .. . . . .. . . .. . . 44.6 Downloaded from www.jbc.org by guest, on January 21, 2010 Fat. .......................... . .. . .. .. . . .. . . 19.4 Cane sugar ................... . .. . .. . . . .. . 9.3 Mineralmatter ............... ...... ...... . 4.2 Crude fiber ................... ...... ...... . 2.3 Moisture ..................... . . 5.3 Non-nitrogenous extract ...... . 14.5 Its content of protein and fat far exceeds that of any other legume, which condition seems to have been appreciated in Japan; for, according to Oshima, it is next to rice in importance in the Japanese dietary.s In addition to cane sugar, the presence of galactans and of pentosans has been detected by Schulze and his collaborators.4 The soy bean does not give the ordinary iodine test for starch.6 2. WHITE BEAN. This was the ordinary white bean of com- merce. 3. CRUDE BEAN PROTEIN. Experiments with the ordinary white bean are subject to the same criticism as has been offered in connection with the work of previous investigators. The attempt was here made to thoroughly rupture the cells and dissolve and wash away the starch. The method in brief was as follows: about 1 Mr. M. F. Deming of the Cereo Company, Tappan, N. Y., very kindly contributed this material. 2 Reported by Ruhriih: Journal of the American Medical Association, liv, p. 1664, 1910. * Oshima, (see bibliography) gives an interesting account of the various soy bean preparations, which are common articles of diet in Japan. 4 For the literature, see Schulze and Godet : Zeitschrift fiir phpiologischc Chemie, lxi, p. 279, 1999. 6 Cf. Oshima: Zoc:cit. p. 26.
4. 436 Utilization of Legume Proteins 5 pounds of finely ground hulled beans1 were mixed with water and heated in a glycerol bath. After the mixture had been held near 100” C. for about an hour, the thin mush which had formed was cooled below 75” C. and a glycerol extract of malt diastase added, as a result of which, after a few minutes, starch could no longer be detected with iodine in a test-tube trial. The material thus obtained was washed by decantation and the water driven off by heat until about 20 per cent was made up of solid matter. The resulting preparation was a thick mush, which could be conven- iently pressed into cakes and preserved frozen. Although no iodine test for starch was obtained in a test-tube trial, nevertheless, Downloaded from www.jbc.org by guest, on January 21, 2010 when a sample treated with this reagent was examined under the microscope, not infrequently starch grains were observed within cells, which had apparently not in any way been affected by the treatment to which they had been subjected. This insufficient rupture undoubtedly accounts for the incomplete conversion of the starch. Analysis of Crude Bean Protein (calculated for anhydrous material). per cent Protein(NX 6.25).......................................... 51.1 Sugar from insoluble carbohydrate (by hydrolysis). . . . . . . . 28.9 Sugar from soluble carbohydrate (by hydrolysis) . . . . . . . . . 2.4 Ash.. . . . . . . . .. . . . . . . . . . . . . . . . . . . . . , . . . 2.6 Ether extract*............................................. 4.0 Crudefiber(bydifference).................................. 11.0 ‘Estimated from Atwaterand Bryant: U. 9. Department of Aprlculture, Bull. 28 (Revised). p. 66, 1906. Material was not available for analysis. Attention is called to the fact that a barley protein preparation2 with approximately the same concentration of protein contained practically no cellular structure or starch, yet yielded 20 per cent of carbohydrate by hydrolysis. The latter was believed to be hemicelluloses. It is thus probable that a not inconsiderable portion of the “carbohydrate by hydrolysis” of the above analysis was in reality also made up of hemicelluloses.3 1 Furnished by Mr. Deming who also prepared a considerable portion of the crude bean protein for us according to the method outlined. a Mendel and Fine: This Journal, x, p. 340, 1911. * At the time of proof reading we learn through a private communication from Prof. E. Schulee that hulled beans, phaseolus vulgaris, contain 12.9 per cent, hemicellulose. We estimate the hemicellulose concentration of our preparation at approximately 25 per cent.
5. Lafayette B. Mendel and Morris S. Fine 437 4. PHASEOLIN. This material was very kindly furnished by Dr. T. B. Osborne. It was dried, ground to an impalpable powder, and found by analysis to contain 13 per cent of nitrogen. 5. PEA GLOBULIN. This material was prepared as follows: dried peas were finely ground and repeatedly extracted with 10 per cent NaCl solution. The perfectly clear extract thus obtained was saturated with ammonium sulphate, the resulting precipi- tate being collected on a filter paper, suspended in a small amount of water to which toluene had been added and dialyzed for about two weeks, that is, until free from sulphates. Part of the prepar- ation was obtained by dialyzing the saline extract, thus avoiding Downloaded from www.jbc.org by guest, on January 21, 2010 the necessity of the precipitation with ammonium sulphate. The resulting precipitate was dried at 40” to 50” C., ground to an im- palpable powder and found by analysis to contain 16 per cent of nitrogen. Metabolism Experiments. SOY BEAN. Man,l Table 1: The ordinary routine was followed: a fore period (preceded by a three day adjustment period), during which a mixed diet was consumed; experimental period, in which over 90 per cent of the nitrogen ingested was furnished by soy bean; and an after period essentially like the fore period. The character of the diet is outlined below: Character of Diet. Dally Averages Daily Averages Daily Aversgea grams grams gram.5 Cracker.................. 70 70 Egg. . . . . . . . .. . . .. 100 200 Peanut butter.. . .. . . . 75 Meat. . . . . . . . . . . . . . . . . 140 190 Soy bean . . . . . . .. . 165 Potato................... loo 120 Tomato.................. 250 375 200 Apple.................... 200 200 200 Orange. . . .. . . . 130 180 130 Milk. . . . . . . . . . .. . 60 60 60 Sugar.................... 130 140 130 Butter.. . . . . , . . . . 50 100 90 Cereal coffee, tea. . . . . . . 600 600 1 The subject was one of us (M. 5. F.) twenty-four years of age, leading the usual active life of the laboratory.
6. 438 Utilization of Legume Proteins As will be observed, during the experimental period the cracker, egg, meat, and nut butter were completely replaced by soy bean, which furnished 91 per cent of the total nitrogen intake of this period. The daily nitrogen and calorific intakes in these periods were fairly constant, averaging about 12.6 grams and 2500 calories, respectively. The soy bean was boiled in water for one-half hour, salted to taste, and the tomatoes thoroughly incorporated into the resulting mush. The palatability of the mixture was still further increased by the addition of a very small amount of pap- rika. On the whole it may be said that this fare proved quite agreeable, no unpleasant symptoms appearing throughout the Downloaded from www.jbc.org by guest, on January 21, 2010 period of six days. TABLE 1. Soy Bean. - BUBmwr, M*N PERIOD II Weight at beginning, 56.8 Kg. (6 days) Weight at end, 56.8 Kg. Soy Bean -- Meat, egg, Soy bean, 1 Meat, egg, po- nut butter, fruit, etc., tato, fruit, potato, 90.5 per cent etc. (No nut Composition of daily fruit, etc. total nitro- butter). diet.. . . . . . . . . . . . . . . . gen supplied by soy bean. Estimated Estmated Estimated calories 240 calories 240(D’ calories 2600 Dtiy Averages Daily Averages Dally Averages Nitrogen output. Urine nitrogen, gm.. . . . . 9.56 10.81 9.69 Total nitrogen, gm.. . , . . 11.11 12.72 11.16 Nitrogen in food, gm . . 12.78 12.93 12.22 Nitrogen balance, gm. . +1.67 +0.21 +1.06 Feces. Weight air dry, gm. . . . . 25.0 26.6 25.2 Nitrogen, gm.. .. . . .. . 1.55 1.91 1.47 Nitrogen, per cent.. . . . . 6.18 7.15 5.88 Nitrogen utilization, pel cent.................... 87.9 85.3 88.0 The subject felt in excellent condition throughout the entire experiment. Defecation took place regularly every morning and no diarrhoea occurred.
7. Lafayette B. Mendel and Morris S. Fine 439 It will be observed from Table 1, that the soy bean nitrogen is distinctly (if only slightly) less well utilized than that of the preced- ing and succeeding mixed diets. The nitrogen concentration of the feces of the soy bean period is higher than in any other experi- ment on this subject which indicates that some soy bean protein escaped absorption. SOY BEAN. Dogs (with agar and bone ash)-Tables 1 to 4: Dog 1, Table 2, was fed with a mixture of soy bean, lard, agar, bone ash and water. It was heated on the water bath for four to six hours, the purpose being to thoroughly “hydrate” the material, which, as fed to the animal, was a thick mush. Downloaded from www.jbc.org by guest, on January 21, 2010 Dogs 6 and 7, Tables 3 and 4, were fed with similar ingredients and sugar in addition. The mixture, including the water, was not heated, but allowed to stand over night, after which the material appeared to be thoroughly “hydrated .” The plan of experimentation differed in no particular from those previously followed, and we may therefore proceed directly to an examination of the tables, which contain all the essential details. In the dog, the soy bean was in every case strikingly less well util- ized than the meat fed under similar experimental conditions, and one also notes the persistently higher nitrogen concentration of the feces of the soy bean periods as compared with that of the meat- feces. This is an indication, as noted above, that some soy bean protein has probably escaped digestion.
8. 440 Utilization of Legume Proteins TABLE 2. Soy Bean with Agar and Bone Ash. BUB.lEc!T,DOG1 PERIOD III PERxoD1vt PERIOD v Wefght at beginning, 15.0 Kg. (5 days) (5 day4 (4 days) Weight at end. 14.6 Kg. Meat Feeding Soy Bean Feeding Meat FeedIng g1(1t?a* prams grama Meat 3g paTdbean 1% ygi 36$Lard C;~e~sition of daily Agar* 5 Agar 5 Agar 5 . .. . .. . .. . .. . .. . . Bone ash 15 Boneash 15 Bone ash 15 Water 300 Water 500 Water 300 Estimated Estimated Estimated I calories 1070 calories 1110 calories 1070 Daily Averages Dally Averages Dsfly Averages Nitrogen output. Downloaded from www.jbc.org by guest, on January 21, 2010 Urine nitrogen, gm.. . . . . . . 10.07 9.25 8.81 Total nitrogen, gm.. . . . . . . 10.60 10.94 9.38 Nitrogen in food, gm.. . . . . 10.38 10.44 10.44 Nitrogen b&c., gm. . . . -0.22 -0.50 +1.06 Weight air dry, gm. . . . . . 29.4 55.6 29.5 Nitrogen, gm. . . . . . . . . . . . 0.53 1.69 0.57 Nitrogen, per cent. . . . 1.79 3.05 1.95 Nitrogen utilization, per cent. . . . . . .. 95.0 83.8 94.5 I I I l On the first two daya of the eriod, the “indineatlble” was represented by 20 grams bone aah. This produced brittle feces. g ence in the remaining three days agrtr and bona ash were em- ployed aa noted in the table. t Forced feedIng necessary throughout the period-no vomftlng. TABLE 3. Soy Be n with Agar al ‘zc 1 Bone Ash. - BUBJECT, noo 5 PERIOD VI PERIOD VII* Weight at begfnnlng. 5.2 Kg. (4 days) (4 dwd Weight at end, 5.2 Kg. Meat Feeding Soy Bean Feeding -_ Meat grams 150 gnwns gronu 150 soy bean Meat Fig Comepyition of daily F3 Agar 3 ii !%? 253 E% Agar Agar ;: 3 .. . .. . .. . .. . .. . .. Boneash 7 Boneash 7 Bone ash Water 100 Water ZOO Water 14 Estimated Estimated Estimated calories 510 calories 570 calories 510 __ Daily Averages Daily Averagea Dally Averages Nitrogen output. .- Urine nitrogen, gm.. . . . . . 3.71 Total nitrogen, gm. . . . . . Nitrogen in food, gm. . . . 4.11 4.93 3.01 4.26 4.90 2z 4:80 Nitrogen b;L;;;e, gm. . . . +0.82 +0.64 +0.36 Weight air dry, &.r. . . . . 15.5 34.0 15.0 Nitrogen, gm.. . .. . . . 0.40 1.25 0.35 Nitrogen, per cent.. . . . . . 2.60 3.67 2.32 Nitrogen utilization, pel cent................... 91.8 74.5 92.7 - = Cystitfa developed but w&8 cured fn the course of two days by means AgNOt solution. 9. Lafayette B. Mendel and Morris S. Fine 441 TABLE 4. Soy Bean with Agar a i Bone Ash. - BlJBJBcr, DOG 7 PERIOD v PERIOD VI PERIOD VII Weight at beglnnlng, 4.9 Kg. (6 days) (5 days) Weight at end. 4.6 Kg. ivf2t%2,ng Soy Bean Feeding Meat Feeding gta?m &mw?u I ~rarnd Meat 100 Soy bean 47 Meat 100 Sugar 20 Sugar 20 Sugar 20 Lard 20 Lard 25 Lard 20 Composition of daily I Agar 3 Agar 3 Agar 3 diet. . . . . . . . . . . . . . . . . Bone ash 7 Bone ash 7 Bone aah 7 Water 100 Water 175 Water 100 Estimated Estimated Estimated Downloaded from www.jbc.org by guest, on January 21, 2010 I calories 430 calories 490 calories 430 -- _- Daily Averages Daily Averages Nitrogen output. _- Daily Averages _- Urine nitrogen, gm.. . . . 2.63 2.38 2.55 Total nitrogen, gm.. .. 2.89 3.04 2.79 Nitrogen in food, gm. . . . . 3.29 3.34 3.20 Nitrogen balance, gm. . . . +0.40 +0.30 +0.41 Feces. Weight air dry, gm.. .. 12.7 20.5 12.8 Nitrogen, gm. . . . . . . . . 0.26 0.66 0.24 Nitrogen, per cent. . . . . . 2.04 3.22 1.86 Nitrogen utilization, per - cent. . . . . . . . . . . . . . . . . . 92.1 - 80.2 - 92.6 SOY BEAN. Dogs (without agar and bone ash)-Tables 6 to 13: These experiments were conducted in essentially the same manner as those just reported, except that the indigestible adjuvants- agar and bone ash-were omitted. Tables 8 to 10 contain the results of trials instituted after the intestinal tract had been sub- jected to a thorough treatment with indigestible non-nitrogenous materials, the purpose being to remove as far as possible the accu- mulated intestinal debris. Proceeding directly to a study of the tables, we again note the poor utilization of the soy bean nitrogen. A fuller discussion of these data with a consideration of the attending conditions will be offered below’ in connection with the discussion of the results obtained with the crude bean protein. In Oshima’s compilation one notes that certain soy bean products (e.g., tofu) are as much as 96 per cent utilizable. Tofu, however, is probably of an albumose nature and such favorable results should be correspondingly interpreted. ‘P. 452. 10. 442 Utilization of Legume Proteins TABLE 6. Soy Bean without Agar or Bone Ash. BUBJECT, DO0 6 PERIOD xxx* Weight at beginning, 6.9 Kg. (5 daya) Weight at end. 6.0 Kg. Soy Bean Feeding grams gmnu Meat 150 Soy bean EEY 2 k:: 2 Composition of daily diet. . . . . . . . . Water 100 Water !z Estimated Estimated 1 calories 530 calories 530 Dally Averagea Dally Averages Nitrogen output. . Downloaded from www.jbc.org by guest, on January 21, 2010 Urine nitrogen, gm ........... 4.08 3.96 Total nitrogen, gm ........... . 4.30 4.66 Nitrogen in food, gm ......... 4.59 4.61 Nitrogen balanwLcr +0.29 -0.05 17.8 Weight air dry, gm ...................... Nitrogen, gm ................. . . . .$12; _... 0.70 Nitrogen, per cent ............ Nitrogen utilization, per cent. 95.2 8E * One-quarter to one-half of the food forced each day. TABLE 6. Sol/ Bean without -Agar or Bone Ash. - i31JBJEcrl, DOB 6 PERIOD XXII Weight at beginning, 6.1 Kg. (6 days) Weight at end, 6.3 Kg. Soy Bean Feeding _- .- @m?zs Dram Composition of daily diet. . . . . . . . . Meat pw$150 E 2; < 3oy bean L 1 1 64 zi Water 100 Water 225 Estimated Estimated 1 1 calories 530 calories ! Daily Averages Nitrogen output. .- Urine nitrogen, gm ................ 3.42 E 4.16 .’ 4:59 4.61 Nitrogen balance~e~~. +0.82 +0.45 Weightairdry,gm ... . ......................... 3.5 18.2 Nitrogen, gm ...................... 0.22 0.74 Nitrogen, per cent ................. 4.04 Nitrogen utilization, per cent. ..... 929 84.0 - - 11. Lafayette B. Mendel and Morris S. Fine 443 TABLE 7. Soy Bean without Agar or Bone Ash. - smmcm, DOG 7 PERIOD xx PEBIOD XXI Weight at beginning, 6.9 Kg. (4 days) (5 days) Weight at end, 6.3 Kg. Meat FeedIng Soy Bean Feeding _- grams g,llWZ* Meat 150 Soy bean c Composition of daily diet. . . . . . . . . ’ !3 ii i%S Water 100 Water 2;: Estimated Estimated calories 530 calories 530 Daily Averama Daily Aversnea Nitrogen output. Downloaded from www.jbc.org by guest, on January 21, 2010 Urine nitrogen, gm .................. 3.55 3.41 Total nitrogen, gm. ................ 3.74 4.21 Nitrogen, in food, gm ............... 4.59 4.61 Nitrogen balanc;;cz +0.85 +0.40 Weightairdry,gm ..I.. ........................... 3.2 16.2 Nitrogen, gm ....................... 0.19 Nitrogen, per cent .................. 5.93 xz Nitrogen utilization, per cent ....... 95.8 82:8 - TABLE 3. Soy Bean without Agar or Bone Ash. SUBJECT, DOG 5 PERIOD XXVI’ PERIOD XXYIII Weight at beginning, 6.2 Kg. (3 days) (5 days) Weight at end, 6.2 Kg. Soy Bean Feedlng Meat FeedIng grama !ara?na Meat 150 ii Sugar 25 Lard Lard Composition of daily diet. . . . . . . . . . Water 2Z Water 1: Estimated Estimated I calories 530 calories 530 Daily Averages Dailv Averarres Nitrogen output Urine nitrogen, gm ............. 3.66 3.68 Total nitrogen, gm. ............ 4.31 Nitrogen in food, gm ............ 4.61 2: Nitrogen balanc;;cz +0.30 +0.&l Weightairdry,gm ..:. ................... 18.5 3.4 Nitrogen, gm. .................. 0.65 0.16 Nitrogen, per cent .............. 3.52 4.62 Nitrogen utilization, per cent . . 85.9 96.6 *About half of the food forced each day. 12. 444 Utilization of Legume Proteins TABLE 9. Soy Bean without Agar or Bone Ash. BUBJEOT, DO(1 6 PlRIOD XXVII Weight at beginnIng 6.6 Kg. (3 da 8) Weight at end. 6.6 Kg. Soy Bean % eedlng Soy bean Meat 150 I pz; 2”; 25 !2% Composition of daily diet. . . . . . . . Water 2% Water 1: Estimated Estimated calories 530 calories 539 Dally Averages Dally Averages Nitrogen output. Downloaded from www.jbc.org by guest, on January 21, 2010 Urine nitrogen, gm.. . . . . . . . . . . . . . 3.45 3.35 Total nitrogen ,fm’ . . . . . . . . . . . . . . 4.06 3.59 Nitrogen in foo , gm.. . . . . . . . . . . . . . 4.61 Nitrogen balance, gm.. . . . . . . . . . . +0.55 Feces. Weight air dry, gm ................... 16.7 4.4 Nitrogen, gm ........................ 0.61 0.24 Nitrogen, per cent ................... 3.64 Nitrogen utilization, per cent. ....... 86.8 9::: TABLE 10. Soy Bean m’thout Agar or Bone Ash. BUBJECT, DOCI 7 PERIOD XXVI PERIOD Mvm Weight at beginning, 6.6 Kg. (4 days) (5 days) Weight at end, 6.6 Kg. Soy Bean FeedIng Meat Feeding grams gmmr Soy bean Meat 150 Composition of daily diet. . . . . . . . p$; Water 22 E Ed? Water ii 109 Estimated Estimated calories 530 calories 530 Daily Averagea Dally Averages Nitrogen output. 3.78 4.35 zz 4.61 4.64 +0.26 +0.89 Weight air dry, gm.. .*. . . . . . . . . 15.9 3.8 Nitrogen, gm.. . . . . . . . . . . . . .. 0.57 0.15 Nitrogen, per cent.. . . . . . . . . .. 3.60 3.82 Nitrogen utilization, per cent. .. 87.6 96.9
13. Lafayette B. Mendel and Morris S. Fine 445 TABLE 11. Soy Bean without Agar or Bone Ash. IOBJECT, DOG 5 PmuOD XVI PHlRIOD XVII We ht at beginning, 6.0 I& (4 days) (4 days) 8 eight at end, 5.9 Kg. Meat Feeding Soy Bean Feeding Meat ;yap Composition of daily diet. . . .. . k.% Lard Water Water Estimated Estimated calories calories Dally Averaaes 1 Dally Averagea Nitrogen output. Downloaded from www.jbc.org by guest, on January 21, 2010 Urine nitrogen, gm ................. 2.77 2.83 Total nitrogen, gm ................. 2.79 3.48 Nitrogen in food, gm ............... 3.28 3.31 Nitrogen balanc$e;;. +0.49 -0.17 Weight air dry, gm ................................. 0.4 14.0 Nitrogen, gm ....................... 0.65 Nitrogen, per cent .................. E; 4.67 Nitrogen utilization, per cent. ...... 99:4* 80.2 * Feces evidently separated Imperfectly. TABLE 12. Soy Bean without Agar or Bone Ash. BUEZJE~~, DOG 6 PERIUOD XVII Weight at beginning, 6.2 Kg. (4 days) Weight at end, 6.1 Kg. Meat Feeding grcrms grams Meat 100 Soy bean ii: Composition of daily diet. ......... ES z 2T Water 150 Water 22 Estimated Estimated calories 450 calories 460 Dally Averages Daily Averages Nitrogen output. Urine nitrogen, gm ........... 2.41 2.49 Total nitrogen, gm ............ . .. . 2.54 3.21 Nitrogen in food, gm ......... . .. . 3.28 3.31 Nitrogen balanc;;cr . .. . . +0.74 +0.10 Weightairdry. gm ..I.. ............... 14.0 Nitrogen, gm ................. kh 0.72 Nitrogen, per cent ............ .. 7.03 5.15 Nitrogen utilization, per cent . . . . . 96.0 79.3 14. 446 Utilization of Legume Proteins TABLE 13. Soy Bean without Agar or Bone Ash. PEBIOD XVII mv?24 !xJELsEm, DO0 7 PERIOD XVI Weight at beginning, 6.0 Kg. (4 days) (4 daya) Weight at end,.&9 Kg. Meat Feeding Soy Bean FeedIng Meat 100 Soy bean 46 sugar 25 Sugar 25 Lard 20 Lard 20 Composition of daily diet .... .. I Water 150 Water 225 Estimated Estimated calories 450 calories 460 Downloaded from www.jbc.org by guest, on January 21, 2010 Daily Averages Daily Averages+ Nitrogen output. - Urine nitrogen, gm. ................ 2.85 2.83 Total nitrogen, gm. ................. 2.95 3.37 Nitrogen in food, gm ................. 3.28 3.31 Nitrogen balance, gm ................ +0.33 -0.06 FeCW Weightairdry,gm.. ................. 1.5 11.0 Nitrogen, gm ........................ 0.10 0.54 Nitrogen, per cent ................... 7.06 4.77 Nitrogen utilization, per cent. ....... 96.8 83.8 WHITE BEAN. Man, Table 14: The original intention was to investigate the digestibility of hulled beans which had been finely ground and thoroughly cooked, and in which the starch had in great part been dissolved by an amylolytic preparation. This mixture, however, produced such violent nausea that a successful experiment with it was entirely out of the question. Indeed other workers, notably Striimpell, have reported similar difficulties with bean experiments. However, the subject was unwilling to have the fore period stand for naught, so the experiment was carried through using ordinary unhulled beans, which were cooked or baked in the usual way. In this form the beans were far from unpalatable. The character of the dietary employed in this experiment is given below: 15. Lafayette B. Mendel and Morris S. Fine 447 PBmm.aN*FzY AriD IPXPEBIMINTAL Foam PlRlODa PIlaOD Dally Averagea Daily Aversgea gm?nJ grams Cracker.. . . . . . . :. . . . . . . . . . . . . . . . . . . . 70 35 Egg. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 90 Meat............................... 206 Beans............................... 230 Potato;............................. 100 Tomato.. ..... . . . .. . .. . . . .. . .. . .. . . . 250 300 Apple. . . . . . . . . . . . . . . . . . ... ... 200 200 Grange. . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 180 Downloaded from www.jbc.org by guest, on January 21, 2010 Grapes. . . . . . . . . . . . . . . . . . . . . . . . . 120 140 Milk.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 60 Sugar. . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 130 Butter.. . . . . . . . . . . . . . . . . . . . . . . . . . . 75 80 Cereal coffee, tea. . . . . . . . . . . 600 600 TABLE 14. White Bean. BUBJEcr, MAN Weight at beginning, 66.4 Kg. Weuht at end. 56.0 Meat, egg, pota- Beans, egg, fruit, to, fruit, etc. etc. 68.2 per cent of total nitrogen Composition of daily diet.. . . . .. . . c supplied by the beans. Estimated Estimated calories 2600 calories 2700 Dally Ave~asee Da!ly Averages Nitrogen output. Urine nitrogen, gm. ................. 9.19 8.00 Total nitrogen, gm. ................. 10.90 10.70 Nitrogen in food, gm ................. 12.25 12.20 Nitrogen balance, gm ................ +1.35 +1.50 Feces. Weight, airdry,gm.. ................ 26.2 44.2 Nitrogen, gm ........................ 1.71 2.70 Nitrogen, per cent ................... 6.54 6.11 Nitrogen utilization, per cent. ....... 86.0 77.9 The plan of the experiment, diiered in no essential from those on man already reported. The preliminary period of adjustment was only one day in duration, and the after period was entirely 16. 448 Utilization of Legume Proteins omitted. The results are in general accord with those obtained by previous observers. The factors which probably contribute to the unfavorable util- ization of the protein of beans have already been discussed.’ The plan was conceived of avoiding these unfavorable influences as far as possible, and to that end, as already described,2 hulled and powdered beans were thoroughly cooked, and the greater part of the starch removed. Experiments with this material follow. CRUDE BEAN PRoTE&--Dogs, Tables 16 to 21: The material was not dried; but when in the stage of evaporation the proportion of solid matter became about 20 per cent, it was pressed into pack- Downloaded from www.jbc.org by guest, on January 21, 2010 ages containing the daily supply of protein, and preserved frozen until ready for use. In some cases, no additional water was given, as the moisture of the product sufficed. Such details may be most readily learned from the tables. In the experiments reported in Tables 15 to 17, the foodmixture was of the consistency of putty and made a rather large volume of material. The animals experienced some difficulty in chewing because of the unusual consistency, but in spite of this Dogs 6 and 7 appeared to relish the fare; and even Dog 5, upon whom forced feeding had to be practiced, did not seem to find the food especially repellent. It was thought that possibly this large mass of food overburdened the digestive tract thus accounting for the rather poor utilization, and hence experiments reported in Tables 18 to 20 were instituted, where the food nitrogen was only two-thirds as great as in the pre- ceding three experiments. In all the above experiments, agar and bone ash were included in the diet, and it was therefore desired to eliminate the influence of these “indigestibles” for comparison. Hence the experiment recorded in Table 21. 1 Cf. Mendel and Fine: This Journd, x, p. 305, 1911. 2 Pp. 435436. * As far as we are aware the only experiments with similar material were conducted by Edsall and Miller (see bibliography) on infants and on a man. The infants digested 90 per cent or over of the nitrogen in the bean periods and the man utilized 94 per cent. However, the bean protein fur- nished but 25 per cent of that of the infant’s food and only about 12 per cent of the protein in the man’s dietary, whereas in our experiments all the pro- tein was supplied by the bean preparation. 17. Lafayette B. Mendel and Morris S. Fine 449 TABLE 15. Crude Bean Protein with Aaar and Bone Ash. - sUBJEc!T. DOG 5 PmRIOD x PERIOD XI’ Weight at beginning. 6.6 Kg. (4 days) (3 days) Weight at end. 6.2 Kg. Meat Feedina 1 Bean F’mtein Feeding _- pVarn* grams Meat 150 Bean orotein 300 , 20 Sugar- 23 20 Lard ;: Agar Agar 2 Composition of daily diet. . . . . . Bone ash f Bone ash 5 7 Water 100 Water (contain- ed in the bean protein) 240 Estimated Estimated Downloaded from www.jbc.org by guest, on January 21, 2010 calories 520 calories 560 Daily Averages Daily Averages output. Nitrogen -- Urine nitrogen, gin.. . . . . . . . . . . . 4.65 4.24 Total nitrogen, gm.. . . . . . . . . . . . . . 4.97 5.08 Nitrogen in food, gm.. . . . . . . . . . . . 5.23 5.10 Nitrogen balanc$e;e;. ... . .. . . . +0.26 +0.02 i Weight air dry, gm.. .‘. . . . . . . . . . . . 11.0 39.3 Nitrogen, gm.. . . . . . . . . . . . . . . . . 0.32 0.84 Nitrogen, per cent.. . . . . . . . . . . . . . 2.95 2.15 Nitrogen utilization, per cent. . . . . 93.8 83.4 *Forced feeding necessary throughout the period. TABLE 16. Crude Bean Protein with - Aaar and Bone Ash. %UBJEcT, mm 6 PERIOD XI PERIOD XII Weight at beginning, 7.1 Kg. (4 days) (3 days) Weight at end, 6.8 Kg. Meat Feedlng Bean Protein Feedtng _- -- *rams gram* Meat 150 Bean protein 3OC& 2% z ES 25 Agar 2 Agar Composition of daily diet. . . . Bone ash Bone ash i Water loi Water(contain- ed in the bean protein) 240 Estimated Estimated calories 520 calories 560 Daily Averages Daily Averages - -- 3.84 3.62 4.20 4.59 5.23 5.10 +1.03 j-o.51 Weight air dry, gm .. .: ........ 9.2 35.3 Nitrogen, gm ...................... 0.36 0.97 Nitrogen, per cent ................. 3.91 2.75 Nitrogen utilization, per cent ....... 93.1 81.0
18. Utilization of Legume Proteins TABW 17. Crude Bean Protein m-t h Agar and Bone 8UB.TmxT, DOQ 7 PEErODx Weight at beginning, 6.7 Kg. Weeht at end, 6.4 Kg. i%&EtFzdng maw Bean protein z Er 25 &w Composition of daily diet. . . . . . . . . . Bone ash f Water(contain- ed in the bean protein) 240 Estimated Estimated Downloaded from www.jbc.org by guest, on January 21, 2010 calories 520 calories 560 Dally Averages Daily Averagea Nitrogen output. Urine nitrogen, gm. ................ 3.51 Total nitrogen, ................. 4.37 Nitrogen in foo c\$” gm ............... , 5.10 Nitrogen beige, gm +0.73 Weight air dry, gk~. ................................ 10.0 36.3 Nitrogen, gm ....................... 0.32 0.86 Nitrogen, per cent .................. 3.20 2.38 Nitrogen utilization, per cent. ...... - 93.9 83.1 TABLE 18. Crude Bea nP ‘rotein with At - and Bone Ac,h. - BUB.JE*, DOG)5 Weight at beginning, 8.2 Kg. W.&&t at end, 5.9 Kg. -- -- gromd Pama 1 grams Meat 100 Bean pro- Meat 100 tein 299 25 sugar ET 20 Lard 2 ES 2 Ciimpostion of daily Aw Bone ash ii 9gar Bone ash E Aw ash i Bone ........ . .. . .. . .. . . Water 150 Water(l60 gm. Water 150 in the bean protein)225 Estimated Estimated Estimated calories 450 calories 480 calories 450 _- Daily Averagea Daily Averages Daily Averages 3.15 3.09 3.43 3.49 3.54 3.34 3:: +0.06 -0.20 +Ei .. 11.0 26.5 11.5 Nitrogen, gm ........... .. Nitrogen, per cent ....... .. X:2 EG 8:Z Nitrogen utilization, Eher cent .................. .. 91.8 83.8 92.1 ’ Forced feeding necessy throughout the period.
19. TABLE 1% Crude Bean Protein with A{ w and Bone Ash. BOBJECT, DOG 8 Weight at beg~nnfng, 6.6 Kg Weight at end, 6.3 Kg. prwna OraM Bean pro- Meat 100 tein 200 23 Agar 25 25 27 Agar 2 Comer of daily Bone ash f *. . . . . . . . . . . . . . . . Bone ash f Water(l60 gm. Water 150 in the bean protein)225 Estimated Estimated Estimated calories 45( calories 480 calories 450 Downloaded from www.jbc.org by guest, on January 21, 2010 D&Y Averages Nitrogen output. Urine nitrogen, gm ...... 2.56 2.40 Total nitrogen, gm ...... 2.91 2.71 Nitrogen in food, gm. ... 3.49 Nitrogen bge;;e, gm +0.58 +E Weight air dry, &I. ........ 10.5 28.3 10.0 Nitrogen, gm. .......... 0.35 0.69 0.31 Nitrogen, per cent:. .... . 3.37 2.45 3.07 Nz;;en utrlmatlon, p .................. 89.8 79.3 90.6 TABLE 20. Crude Bean Protein with Agar and Bone Ash. I BUBJECT, DOG 7 PEELIOD xn PERIOD XI” Weight at be&.mlng, 6.4 Kg (4 days) Weight at end, 6.1 Kg. Meat FeedIng grama gram grama Meat 106 Bean pro- Meat 100 tein 206 p-%; Aw- Ei 2 E% Agar 2 Lard Atw sugar Ei Corrption of daily Boneash 5 Bone ash E Bone ash : . . . .. . .. . .. . .. . .. . Water 150 Water(l60 gm Water 150 in the bean protein) 22, Estimated Estimated Estimated calories 450 calories 480 calories 450 Daily Averagas Daily Averages Daily Averages Nitrogen output. Urine nitrogen, gm.. . . . . 2.82 2.70 2.55 Total nitrogen, .. . . . . 3.05 3.34 2.81 Nitroge In in foo Y, gm.. . . 3.49 3.34 Nitrogen b;i;sce, gm.. . +0.44 e0.00 +E Weight air dry, &.I. . . . . . 25.3 Nitrogen, gm. . . . . . . . . . . E3 E6 Nitrogen, per cent.. . . . . . 2.74 X:E 2.70 Nitrogen utilization, p cent.. . . . . . . . . . . . . .: 93.3 so.9 92.2 451
20. 452 Utilization of Legume Proteins TAFGE 21. Crude Bean Protein without Agar or Bone Ash. suB.mm, DOG 7 PERIOD XVI PERlOD XIX Weight at beginning. 6.0 Kg. (4 days Weight at end, 5.9 Kg. Meat Fee d Ing Bean F&%%edtng grams prom* Meat 100 Bean protein 235 Sugar 25 Sugar 25 Lard 20 Lard 20 Water 150 Water (130 gm. Composition of daily diet., .. . .. . .. in the bean protein) 230 Estimated Estimated Downloaded from www.jbc.org by guest, on January 21, 2010 calories 450 calories 430 Daily Averages Nitrogen output. Urine nitrogen, gm. . . . . . . . . . . 2.35 2.53 Total nitrogen, gm. . . . . . . . . . . 2.95 3.21 Nitrogen in food, gm. . . . . . . . . . 3.23 3.43 Nitrogen balance, gm.. . . . . . . +0.33 +o.n Feces. Weight air dry, gm. . . . . . . . 1.5 24.6 Nitrogen, gm.. . . . . . . . . . . . . . . 0.10 0.63 Nitrogen, per cent. . . . . . . . . . 7.06 2.57 Nitrogen utilization, per cent. 96.8 81.5 One would at once gain the impression from these results that the legume proteins are among the less well utilized materials; nor is this view dispelled when we attempt to analyze certain pos- sible contributing causes. The bean diets contained celluloses and hemicelluloses, substances inherent in the experimental mate- rial and entirely or for the most part indigestible. The influence upon utilization of such non-nitrogenous matter cannot be ascer- tained from the foregoing tables. In a few instances the attempt has been made to determine the amounts of these substances which have failed to disappear from the alimentary tract. The crude fiber of the food may be assumed to completely reappear in the feces.’ The undigested hemicelluloses of the excrement was determined by the method outlined in a previous paper.2 These data are presented in Table 22 and are in part reproduced in Table 1 Cf. Swartz: Transactions of the Connecticut Academy of Ark and Se+ ences, xvi, p. 263, 1911. * Mendel and Fine: This Journal, x, p. 339, 1911.

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