Elements, essential mineral

Fig. 1. Periodic Table showing elements of importance in biological systems principal element of bioorganic compounds essential mineral nutrients for humans and other animals 1 essential mineral nutrient for animals, probably for humans M present in body, not known to be a nutrient or toxic element M element used in medicine element generally poisonous and present in body, possibly toxic.

The essential mineral nutrients are classified either as principal elements or as trace and ultratrace elements. The distinction between these groups is the relative amounts ia the dietary requirement (see Table 1). 

The elemental and vitamin compositions of some representative yeasts are Hsted in Table 1. The principal carbon and energy sources for yeasts are carbohydrates (usually sugars), alcohols, and organic acids, as weU as a few other specific hydrocarbons. Nitrogen is usually suppHed as ammonia, urea, amino acids or oligopeptides. The main essential mineral elements are phosphoms (suppHed as phosphoric acid), and potassium, with smaller amounts of magnesium and trace amounts of copper, zinc, and iron. These requirements are characteristic of all yeasts. The vitamin requirements, however, differ among species. Eor laboratory and many industrial cultures, a commercial yeast extract contains all the required nutrients (see also Mineral nutrients). 

Cobalt is one of twenty-seven known elements essential to humans (28) (see Mineral NUTRIENTS). It is an integral part of the cyanocobalamin [68-19-9] molecule, ie, vitamin B 2> only documented biochemically active cobalt component in humans (29,30) (see Vitamins, VITAMIN Vitamin B 2 is not synthesized by animals or higher plants, rather the primary source is bacterial flora in the digestive system of sheep and cattle (8). Except for humans, nonmminants do not appear to requite cobalt. Humans have between 2 and 5 mg of vitamin B22, and deficiency results in the development of pernicious anemia. The wasting disease in sheep and cattle is known as bush sickness in New Zealand, salt sickness in Florida, pine sickness in Scotland, and coast disease in AustraUa. These are essentially the same symptomatically, and are caused by cobalt deficiency. Symptoms include initial lack of appetite followed by scaliness of skin, lack of coordination, loss of flesh, pale mucous membranes, and retarded growth. The total laboratory synthesis of vitamin B 2 was completed in 65—70 steps over a period of eleven years (31). The complex stmcture was reported by Dorothy Crowfoot-Hodgkin in 1961 (32) for which she was awarded a Nobel prize in 1964. 

White, P. J., Broadley, M. R. (2005a). Biofortifying crops with essential mineral elements. Trends Plant Sci., 10, 586-593. 

Trace Elements as Mineral Nutrients. Within this group of elements are copper, zinc, iron and manganese. All of these minerals are supplied during the cultivation of citrus fruit, and are essential as plant nutrients. They are important in many of the enzymatic reactions in the metabolic activities of the body. 

Of the essential mineral elements, those likely to be deficient in poultry diets are calcium, phosphorus, sodium, copper, iodine, manganese, selenium and zinc. Deficiencies of the other essential mineral elements are less common and the feeds used probably contain them in sufficient quantities. There are some indications that magnesium supplementation may be beneficial under certain situations. 

Golub MS, Han B, Keen CL. 1996b. Developmental patterns of aluminum and five essential mineral elements in the central nervous system of the fetal and infant guinea pig. Biol Trace Elem Res 55 241-251. 

There is great interest in the volatile hydride forming elements as mineral pathfinders , as pollutants and, for selenium at least, as an essential dietary element. There are no existing alternative methods for the elements which are both accurate and cost-effective and there is little doubt that hydride methods will be used extensively in the near future. 

Heating a vitamin will destroy its potency by breaking the compound into other compounds. In contfast, heating a compound that contains one of the essential minerals might destroy the compound, but it will not change the mineral into another element. For example, calcium cihate can be changed into another calcium-containing compound, but the calcium is still present. 

Vitamins are organic compounds necessary for growth and health and cannot be synthesized in sufficient quantities for physiologic health by the body. Therefore they must be obtained from food sources or supplementation. Inorganic essentials (minerals are trace elements) are required in much smaller quantities than vitamins. In general, minerals and trace elements aid and support physiologic functions and, like vitamins, must be obtained from dietary soinces. 

Micronutrients are subdivided according to the quantities needed in the human diet. If more than 100 milligrams (mg) per day of an element is needed, it is classed as a mineral. The seven essential minerals are calcium, magnesium, pho hwus, sodium, potassium, sulfur, and chlorine. Substances that are essential but needed in amounts cf less than 100 mg per day are called trace elements. These are iron, copper, iodine, manganese, zinc, molybdenum, selenium, and chromium. There are likely others (such as boron) that are yet to be identified. 

Phosphorus is an essential mineral element. Phosphorus homeostasis in the body is controlled by hormonal and renal control systems. Phosphorus intoxication from excessive consumption in food is not known. Toxic exposures have been reported to occur from its industrial use or from suicidal ingestion of phosphorus-containing materials. Phosphorus is highly toxic to humans and animals. The acute lethal dose in humans is lmgkg . ... 

Figure 30-26 Metabolism of copper. (Modified from Harris ED. Copper, In O Dell BL, Sunde RA, eds. Handbook of nutritionally essential mineral elements. New Vbr/c /Morce/ DeWcer, 1997 231-73.)...

Klevay LM. Trace element and mineral nutrition in ischemic hart disease. In Bogden JD, Klevay LM, eds. Clinical nutrition of the essential trace elements and minerals. Totowa, New Jersey Humana Press, 2000 251-71. 

O Dell BL, Sunde RA. Handbook of nutritionally essential mineral elements. New York Marcel Dekker, 1997. 

Clinical Nutrition of the Essential Trace Elements and Minerals The Guide for Health Professionals, edited hy John D. Bogden and Leslie M. Klev, ... 

The rate of growth and reproduction of organisms depends not only upon the availability of carbon, water and energy but also upon a variety of essential mineral nutrients. In Chapter 2 we saw that a number of elements are important, such as N in chlorophyll and amino acids, P in ATP and phospholipids, Si in diatom tests and Ca in coccoliths. Some of these essential elements (e.g. N, P, Ca and Si) are generally abundant, and so can be termed macronutrients, whereas others (e.g. Fe and Mg) are required by organisms in only trace amounts and are called micronutrients. 

Mineral Constituents. Cellulose fibers usually contain about 1% ash. The mineral elements contained in the ash include all those essential for the growth and development of cellulolytic microorganisms. This fact has led to speculations and certain experimental treatments by Baechler (4) and others showing that chelating agents applied to cotton or wood can so effectively bind these essential mineral elements that the growth of cellulolytic microorganisms is prevented. 

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