Nutritional Studies

The history of the discovery and the determination of structure of biotin has been well documented recently (130,396,398) and need not be repeated here except to connect up with the topic of the review. Attention should. 

The observations of Wildiers (420) on the growth requirements of yeast, when small inocula were used for propagation in media of simplified composition, initiated the study of the growth requirements of yeasts in terms of the chemical composition of the medium needed for optimal growth. Thereafter, methods of study and an orientation of viewpoint were gradually evolved which resulted in a clear conception of the problems of yeast nutrition, which were seen to be no different in kind from those of other organisms (423). 

Biotin was discovered and isolated by K6gl and Tonnis (160) using a yeast strain, Basse M, and an incre ed rate of growth under defined conditions as the biological test. Biotin was shown to be very widely distributed in biological materials of all kinds, including plant and animal tissues. Thus another part of the yeast bios complex, already separated into several distinct fractions, was identified. 

The third line involving biotin was the study of animal nutrition, first with rats, later extended to other animals. Here characteristic symptmns of egg-white injury were observed by Boas (27) in rats fed a diet contain-ing egg-white as the source of protein. It was found that the animals could 

The chemical work has been reviewed by Hofmann (130) and Melville (245a). For present purposes the effects of biotin in the nutrition of higher animals will be omitted and attention confined to micro-organisms. 

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W. R. Aykroyd and J. Doughty, Wheat in Human Nutrition, FAO Nutritional Studies, No. 23, Food and Agricultural Organi2ation, Rome, 1970, p. 1. 

This method can be appHed to large-scale nutrition studies. 

Although riboflavin can be assayed more readily by chemical or microbiological methods than by animal methods, the latter are preferred for nutritional studies and as the basis of other techniques. Such assays depend upon a growth response the rat or chick is the preferred experimental animal. This method is particularly useful for assaying riboflavin derivatives, since the substituents frequently reduce or eliminate the biological activity. 

Heat is measured in term.s of the calorie, defined as the amount of heat necessary to raise the temperature of 1 gram of water at a pressure of 1 atmosphere firom 15 to 16 °C. This unit is sometimes called the small calorie, or gram calorie, to distinguish it from the large calorie, or kilocalorie, equal to 1000 small calories, which is used in nutritional studies. In mechanical engineering practice in the United States and the United Kingdom, heat is measured in British thermal units (Btu). One Btu is the quantity of heat required to raise the temperature of 1 pound of water 1 ° F and is equal to 252 calories. 

In an analytical laboratory, there must be complete confidence between laboratory and client. All results belong to the client and must not be disclosed to others. There was a case, for instance, where some special methods were developed in connection with a nutritional study. This involved an analysis of monkey feces. The laboratory did not announce that it had newly developed methods, since these really belonged to the client. 

Reiter H, Ertel H, Wendt H, Pies Prater J, Barth L, Schroder H, Catel W, Dost F and Schneunert A (1938) Nutritional studies on the effects of vegetables produced with and without fertilisers . Emahrung (Liepzig), 3, 53-69. 

DF and antioxidants are generally addressed separately as groups of food constituents in both chemical and nutritional studies. However, it is a little-known fact that a substantial proportion of the antioxidant polyphenols and carotenoids contained in fruit and vegetables are linked to DF (Saura-Calixto and others 2007), and some of the postulated benefits of fiber intake can be attributed to these associated compounds. These compounds are not bioaccessible in the human small intestine, but they... 

Saura-Calixto F and Goni I. 2004. The intake of dietary indigestible fraction in the Spanish diet shows the limitations of dietary fibre data for nutritional studies. Eur J Clin Nutt 58 1078-1082. 

American Institute of Nutrition Ad Hoc Committee on Standards for Nutritional Studies. J. Nutr. 1977, 107, 1340-48. 

Glanded cottonseed has been used to produce a defatted cottonseed flour with reduced gossypol content by a procedure known as the liquid cyclone process (LCP). LCP cottonseed flour has been used in the preparation of many foods that have been tested in several animal and human nutrition studies. The commercial production of LCP cottonseed flour has not been successful (5). 

Over the next six years Hopkins pursued, intermittently, the search for the other nutrients required to keep an animal alive and in good health. In 1912 came the published results of his research and while he confirmed them in publications of 1913 (12) and 1920 (13), it appears that other pioneers in nutritional studies, Osborne and Mendel in particular, were unable to repeat or reproduce his results. 

When the prisoners-of-war in the Far Blast were freed, a picture of malnutrition was revealed which was the result of inadequate food, debilitating disease and enforced labour during three-and-a-half years of captivity. The story is here told by medical officers who were themselves prisoners, and the material they collected with little or no conventional apparatus makes no mean contribution to science. Valuable nutritional studies were made also on groups of prisoners after liberation, by medical relief teams, and at bases overseas during evacuation. 

Mn was first shown to play an important role in photosynthetic 0 evolution by nutritional studies of algae (7). The stoichiometry of Mn in photosystem II was determined by quantitating Mn released from thylakoid membranes by various treatments (8). These experiments established that Mn is specifically required for water oxidation and that four Mn ions per photosystem II are required for optimal rates of 0 evolution (9). More recently, photosystem II preparations with high rates of Oj evolution have been isolated from a variety of sources (for a review see 10). The isolation of an O2-evolving photosystem II has proved to be a major step forward in both the biochemical and spectroscopic characterization of the O2-evolving system. These preparations contain four Mn ions per photosystem II (11), thus confirming that four Mn ions are functionally associated with each O2-evolving center. 

Wiseman H, Casey K, Clarke DB, Barnes KA, Bowey E. Isoflavone aglycone and glucoconjugate content of high- and low-soy U.K. foods used in nutritional studies. J. Agric. Food Chem. 50,1404— 1410, 2002. 

Lipids may also be involved in the calcification of the dentine matrix, because sudanophilic materials have been detected in ontoblasts, at the dentine-predentine junction and in the peritubular dentine matrix311. A series of nutritional studies have shown that dentine lipids are in a dynamic state312-315. A diet deficient in essential fatty acids produced degenerative effects on dentinogenesis and resulted in the production of teeth more susceptible to dental caries315. ... 

Food and Agriculture Organization of the United Nations. Food Policy and Food Science Service Nutrition Division. 1970. Amino acid content of foods and biological data on proteins. FAO Nutritional Studies No. 24, Rome. 

Lowe, C. M., Kotula, K. T. and Briggs, G. M. 1983. Nutrition studies of real nonfat and fabricated dry milks with respect to the Food and Drug Administration s 1978 proposal for the nutritional equivalence (NE) of low-fat milk substitutes in rats. J. Dairy Sci. (Suppl. 1) 66, 90. 

Reiter, B. and Oram, J. D. 1962. Nutritioned studies on cheese starters. I. Vitamins and amino acid requirements of single strain steirters. J. Dairy Res. 29, 63-77. 

In the early 1940s nutritional studies of young animals raised on diets lacking animal proteins and maintained out of contact with their own excreta (which contained vitamin B12) demonstrated the need for "animal protein factor" which was soon shown to be the same as vitamin B12. The animal feeding experiments also demonstrated that waste liquors from streptomyces fermentations used in production of antibiotics were extremely rich in vitamin B12. Later this vitamin was recognized as a growth factor for a strain of Lactobacillus lactis which responded with half-maximum growth to as little as 0.013 pg/l(10-nM). 

Fixation of N2 by Clostridium pasteurianum and a few other species was recognized by Winogradsky4 in 1893. Subsequent nutritional studies indicated that both iron and molybdenum were required for the process. Inhibition by CO and NzO was observed. While ammonia was the suggested product, the possibility remained that more oxidized compounds such... 

Vanadium and chromium have been shown to be essential by nutritional studies. Of the remaining metals, it appears possible that tin and tungsten may be essential. The biological properties of the essential metalloids such as selenium1035 and arsenic1060 will not be considered. 

Jobling, M. (1983). A short review and critique of methodology used in fish growth and nutrition studies. Journal of Fish Biology 23,685-703. 

P has a 14.3-day half-life and emits an energetic f particle, making 21P useful for nutritional studies in plants and animals. A 0.01 - xCi sample of 32P in the form of a soluble phosphate was added to a hydroponic bath containing a young tomato plant. Exactly three weeks later, the entire plant was rinsed, dried, and liquefied in a blender. A portion of the preparation was placed in a total activity counter. In a 1.00-min period an average of 625 counts was recorded. How efficient was the tomato plant in utilizing the phosphorus ... 

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