Mineral bioavailability interactions

O Dell LB (1997) Mineral-ion interaction as assessed by bioavailability and ion channel function. In O Dell BL and Sunde R, eds. Handbook of Nutritionally Essential Mineral Elements. Marcel Dekker, Inc, New York-Basel-Hong Kong, pp. 651-659. 

Bioavailability of Metals, Nonmetals and Xenobiotics Immobilized on Soil Components, (4) Distribution and Activity of Biomolecules in Terrestrial Systems, (5) Interactions between Soil Microbial Biomass and Organic Matter/Nutrient Transformations, and (6) Impact of Interactions among Soil Mineral Colloids, Organic Matter and Biota on Risk Assessment and Restoration of Terrestrial Ecosystems. There were 2 plenary lectures, 9 invited speakers, 36 oral presentations and 45 posters. Dr. N. Senesi from University of Bari, Italy, presented an IUPAC lecture entitled Metal-Humic... 

The concept of bioavailability was developed to explain the difference between the total amount of mineral in a food and the amount which was used by the individual consuming the food. Over the past sixty years or more, there have been numerous studies related to dietary calcium requirements and bioavailability (1,2). As a result, much is known about non-calcium food components which influence the absorption and utilization of dietary calcium under experimental conditions. What now is lacking is a detailed knowledge of how these factors interact with calcium under normal conditions of ingestion in meals. 

A couple of theories have been proposed to explain how dietary Ca might possibly affect Se utilization. It has been suggested that Se availability may be directly influenced by intestinal interactions involving Ca or minerals linked to Ca utilization (e.g., phosphorus) (Lowry et al., 1985). Indirect effects on the capacity of a target tissue to respond to Se are also considered possible means by which bioavailability or retention might be influenced (Parizek, 1978). It has also been conjectured (Hill and Matrone, 1970 Howell and Hill, 1978) that elements with valence shell electronic structures most similar to Se (i.e., Se , Se, and Se " ") are most likely to act antagonistically. Based on this criterion, Ca does not fit the profile of a probable Se antagonist. 

Masaphy and Mandelbaum (1997) indicated that long-term irrigation with treated wastewater increased organic matter in soil but decreased the overall mineralization rate of atrazine. The authors indicated that initial atrazine mineralization was greater in soils irrigated with treated wastewater, but after a few days of interaction between the soil and the applied herbicide, mineralization rates decreased as a result of decrease in bioavailability. 

Morse, J. W., 1994, Interactions of trace metals with authigenic sulfide minerals Implications for their bioavailability Marine Chemistry, v. 46, p. 1 -6. 

The physiological interaction between different essential trace elements and also with the other essential major minerals can have significant effects on health. Such interactions are mostly considered as affecting the intestinal bioavailability of nutrients from various diets. The complex interactions that were investigated systematically in animal studies have been important in trying to understand the mechanisms of... 

Interactions among minerals affecting their utilization are currently an area of intense investigation. Greger has reviewed impacts of phosphorus and calcium on iron utilization in this book. Interactions of iron with copper and zinc have also been established (14-16). If minerals compete with iron for absorption binding sites, adverse effects on iron bioavailability may occur. 

The many mineral interactions which influence the safe dietary levels of essential and toxic elements are partly represented in Figure 3.2. While interactions involving dietary elements may be either detrimental or beneficial, the major concern is that an antagonistic element may induce a deficiency of its counterpart nutrient whose concentration in the diet is borderline. The assessment of such in-vivo interactions will be considered here under the limits of bioavailability, which occurs at the site of absorption in the intestinal mucosa or the redistribution from one tissue to another one. Figure 3.2 illustrates the most important, quite different, species-specific interactions of metals, trace and macro elements, respectively, with net requirements in animals and man. Clearly, there are interrelationships in the metabolism of the mineral elements consumed. 

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