Deficiency Of Essential Nutrients Research Articles

Biological and physiological factors in soybeans.

There are limitations to which one is justified in drawing broad generalizations concerning the diverse biological and physiological effects of soy protein products. Nevertheless, there appear to be two distinct situations: (A.) Proper heat treatment exerts a beneficial effect upon the nutritive value of whole soybeans, full‐fat and defatted meal. Associated with proper heating is inactivation of trypsin inhibitor and other heat‐labile factors and conversion of raw refractory proteins to forms that are more readily digested. (B.) Moist heat also has a beneficial effect upon the nutritive value of soy protein isolates. However, a deficiency of certain essential nutrients and the interaction of phytic acid with protein, vitamins, and minerals during processing are the primary factors responsible for the poor nutritive value of soy isolates. Occasionally mineral deficiency symptoms do occur in animals fed soybean meal. It is a misnomer to refer to the growth‐inhibiting and pancreatic hypertrophic properties as a “toxic” effect since both properties are reversible. Modern analytical techniques should be used to reinvestigate the relationship between phytic acid and availability of minerals and vitamins in soy protein isolate diets. Research also is needed to determine more accurately vitamin and mineral contents of soy protein isolates and the availability of vitamins and minerals in soy protein concentrates. Breeding soybean varieties genetically deficient in antinutritional and nonflatulent factors does not appear promising. More research is needed to determine whether fermentation and enzyme processes can be used to prepare flatulent‐free soy products. Minor factors to be considered in assessing the nutritive value of soy products include a weak goitrogen present in soybeans, and a very low estrogenic activity.

Epidemiology of periodontal disease in Western Nigerians in relation to socio-economic status

An epidemiological survey was carried out in the Yoruba ethnic group of Western Nigeria in 1965. The survey was undertaken to determine the relation of periodontal health to socio-economic status, and included 941 persons. The age groups between 5 and 19 yr comprised 53 per cent and 95 per cent of the low and high socio-economic communities respectively. Russell's Periodontal Index (PI) and the Simplified Oral Hygiene Index (OHI-S) comprising the Debris and Calculus Indices (DI-S and CI-S) were recorded. Evaluation of the nutritional status of the communities was carried out by studies of the dietary intakes and the biochemical estimation of blood haemoglobin, serum proteins and serum ascorbic acid levels. In both communities, CI-S and age were closely correlated with PI. At all ages, the same level of CI-S was associated with a higher PI score in the low than in the high socio-economic group. Multiple correlation analysis indicated some residual variation in PI not accounted for by age, CI-S and DI-S, and this was more evident in the low socio-economic group. Clinical, dietary and biochemical studies suggested marked deficiencies of essential nutrients in the low socio-economic group. The survey showed that, in addition to the oral hygiene, due attention should be paid to the host state and his environment in planning prophylactic measures for periodontal lesions especially in malnourished populations.

Effect of sulphate nutrition on flavour components of onion (Allium cepa)

AbstractIt is known that the volatile components of raw and cooked onions contain mono‐, di‐ and tri‐sulphides and other flavour‐contributing sulphur compounds. The relationship between the sulphate nutrition of spring (salad) onion (Allium cepa) and its flavour strength determined by sensory, biochemical and chromatographic methods has been investigated. The plants were grown in sand culture in a glasshouse and the nutrient solutions contained five levels of sulphate from zero to an adequate amount. In their growth response, total sulphur content and visual symptoms, the plants showed characteristic essential nutrient deficiency. The sensory tests, and instrumental and biochemical assays showed that flavour strength increased approximately in proportion to sulphate concentration in the medium; lachrymatory potency also increased. There were significant coefficients of correlation between sulphate concentration of the nutrient medium and some aspects of flavour strength. The correlation coefficients between total sulphur content (% of the edible portion) and total peak area, n‐propyl disulphide peak area and total pyruvate were also high. These observations suggest the possibility of control of onion flavour strength and lachrymatory potency, under field conditions, by control of sulphate nutrition. The question of loss of maximum potential onion flavour as a consequence of sulphur deficiency in soils is discussed.A headspace method for sampling onion flavour volatiles and for their introduction into gas chromatographs is described.

Guilt by Association?

Historically, aminoacidurias have been associated with mental disease. Enzymatic defects in amino acid metabolism, resulting in an accumulation of toxic substances or a deficiency of essential nutrients, may produce mental deficiency. Such cause- and-effect relations, however, were difficult to establish in many aminoacidurias originally reported in mentally retarded persons. It appeared as though many such associations resulted from the sampling bias of urine screening programs that were frequently carried out only in mental institutions. In this issue of the Journal (page 783) the report of an association between cystinuria and mental disease, when such an association was not orginally believed . . .

The magnesium requirements of arable crops

AbstractMagnesium is an essential plant nutrient but magnesium deficiency occurs fairly widely in Europe and North America, especially on light soils. In Great Britain this is known to be so for many horticultural crops, although information on deficiencies in agricultural crops is limited.Magnesium sulphate applied to the seedbed for potatoes increased yield in some but not all experiments on light soils, while in a few on both early and main crop potatoes it depressed yield.Deficiency symptoms often seen in cereals and sugar beet are usually transient, and in almost all experiments on these crops applying Mg has not increased yield.There is a well established interaction between Mg and K, and high rates of the latter can intensify deficiency symptoms and reduce the Mg content of the crop. Field experiments strongly suggest that the induced Mg‐deficiency from heavy rates of applied potash seldom reduces the yield of potatoes, cereals or sugar beet.Methods of controlling or averting Mg deficiency are discussed.

The deoxyribose nucleic acid slime layer of some halophilic bacteria.

Cells of Micrococcus halodenitrificans and Vibrio costicolus when grown under certain conditions possess a sticky extracellular deoxypentose nucleic acid (DNA) slime. Treatment of these cells with deoxyribonuclease (DNase) eliminates the stickiness and removes up to 50% of the DNA of the cells, without affecting their viability. A similar DNA slime is probably responsible for the stickiness of Pseudomonas salinaria and other halophiles, and the presence of such a slime seems peculiar to halophiles. The stickiness of M. halodenitrificans and the amount of DNA extractable from it with DNase decrease with increasing salt content of the growth medium, or if calcium is added to the medium. The results suggest that a deficiency of essential nutrients affects the permeability of the membrane allowing leakage of DNA or its precursors from the cell.

Medical Evaluation of Nutritional Status. Part VIII. The School Lunch as a Method for Improving Diets of High School Students

IT has often been suggested that the school lunch offers an opportunity to make up some of the deficiencies in the home diet of school children and to influence their food habits. The extent to which a high school cafeteria can function with respect to these two objectives is uncertain and no experimental work in this field has come to our attention. The relative frequency and extent of deficiencies of essential nutrients in diets, it is believed, afford a reasonable guide for needed modifications in dietary habits of special groups of the population. In a previous report (i), the prevalence of diets below recommended allowances for specific food elements was presented for a high school group in New York City. This information is utilized in the present report as a basis for suggestions for improving the school lunch as a source of the food values which were most commonly deficient. In New York City, a majority of students in public high schools purchase lunch in the school cafeteria, many others who carry lunch to school purchase some supplementary food, and a small group receive free lunches. Through careful planning of food items offered for sale, and some attention to making the more nutritious items attractive, psychologically and economically, the school cafeteria has an opportunity to influence the consumption level of essential food elements. Diet histories, obtained by interview, were available for 2,037 pupils as part of an investigation on Evaluation of Nutri1This paper is the eighth of a series from a cooperative investigation by the United States Public Health Service, Division of Public Health Methods; the Cornell University College, Department of Public Health and Preventive Medicine and Department of Pediatrics; the Milbank Memorial Fund; and the New York City Department of Health. The cooperating agencies have been assisted in carrying out this investigation by the Work Projects Administration for the City of New York, Official Project No. 65-1-97-21, W.P. 24, Medical Evaluation of Nutritional Status.

The Relation of the Vitamin B Complex to Tumor Growth

Caloric restriction without any deficiency in essential nutrients or the lack of certain essential amino-acids in the diet has been shown to influence the development and rate of tumor growth (1, 2). Tumor growth is therefore definitely dependent upon the intake of exogenous nutrients by the host. So-called synthetic diets were not required to prove this point, but without the use of such a diet an investigation of the influence of essential nutrients becomes most difficult. It is the purpose of this paper to present our progress in this problem. The basal diet finally chosen for these studies consisted of vitamin-free casein, starch, Crisco, agar, and salt mixture. On this diet mice rapidly lost appetite and weight, and tumor growth was markedly retarded, in some cases even inhibited. In the experiments to be recorded various nutrients were added to this basal diet and a study was made of their influence upon the somatic and tumor growth of mice of the Marsh-Buffalo strain inoculated with sarcoma 180.

THE CHEMISTRY OF VITAMIN C

IDENTIFICATION A primary requisite for studying the chemical nature of vitamin C was provided by Hoist and Frolich 1 when they observed that the guinea pig could be used as an experimental animal for the study of scurvy. The experimental diets and general technic developed by Cohen and Mendel 2 and La Mer, Campbell and Sherman 3 then made it possible to measure antiscorbutic activity in a satisfactory quantitative manner, free from interference by deficiencies in other essential nutrients. Attempts to isolate the vitamin from natural products encountered great difficulty, however, because of its extreme sensitiveness to destruction by oxidation. By 1931 many investigators, particularly Zilva and his associates, 4 Bezssonoff and his associates 5 and King and his associates 6 had succeeded in concentrating the vitamin to such a degree that approximately 1 to 2 mg. of solids daily served to protect young guinea pigs from scurvy. The isolation