Macroelement

Pesticides may change the soil s element content. Some pesticides may increase plants micro- and macroelement content, such as nitrogen, phosphorus, calcium, potassium, magnesium, manganese, iron, copper, barium, aluminum, strontium and zinc, whereas others decrease these or other elements. Pesticides may cause ammoniac compounds to accumulate in the soil. Dimethoate and fluometuron increase nitrates in the soil, while DDT, carbaryl and HCH sharply decrease them. When prometrin was used, soil nitrate content decreased by 30-40% [3]. 

The biogeochemical turnover of nitrogen is about 50 kg/ha per year. A similar value was shown for the turnover of total mineral elements, 47 kg/ha/yr. The relevant values for various trace and macroelements are shown in Table 8. 

The determination of distribution pattern of various forms of both macroelements and heavy metals in soil profile is a very complicated task. We have to know the... 

Macroelements, as well as basic elements are essential for plant and animal organisms. They are the building materials that support tissue, teeth, skin, and hair, play an important role in water-electrolyte management and pH regulation, and are parts of many active compounds vital for metabolic processes. 

The elements essential for life can be divided into macroelements (daily requirement > 100 mg) and microelements (daily requirement < 100 mg). The macroelements include the electrolytes sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg), and the nonmetals chlorine (Cl), phosphorus (P), sulfur (S), and iodine (I). 

The last column in the table lists some of the functions of minerals. It should be noted that almost all of the macroelements in the body function either as nutrients or electrolytes. Iodine (as a result of its incorporation into iodothyronines) and calcium act as signaling substances. Most trace elements are cofactors for proteins, especially for enzymes. Particularly important in quantitative terms are the iron proteins hemoglobin, myoglobin, and the cytochromes (see p. 286), as well as more than 300 different zinc proteins. 

Morama is a good source of macroelements such as potassium, phosphate, magnesium, and calcium as well as the trace elements zinc, iron, and copper (Amarteifio and Moholo, 1998 Holse et al., 2010 Wehmeyer et al., 1969), as summarized in Table 5.5. 

Minerals such as Na, K, Ca, and Mg constitute the macroelement in vermouth, whereas Cu, Fe, Mn, and Zn are the major microelements. A comparison of grape vermouth with other vermouths in terms of mineral composition is illustrated in Table 8.12. 

A method is presented for producing concentrate of dehydrated Jerusalem artichoke tubers. The novel product is characterized by a high content of micro- and macroelements (e.g., silicon, potassium, phosphorus, and magnesium). It provides a biologically active additive for foodstuffs, a base or component of food products, and can also be a source material for the production of inulin for use in the biotechnological, medicine, cosmetics, and pharmaceutical industries. 

A method for reproducing Jerusalem artichoke by culturing seedlings on a vernalization bed is disclosed. Seedlings are grown to 15 to 20 cm in height, cut into segments, cultured in medium (prepared from humus, fertilizer, trace elements, and macroelements),... 

Elements such as B, Cd, Co, Cr, Mo, Ni, Pb and V are also often found in foodstuffs at concentrations too low to be amenable to direct flame absorption. Resort must be made to concentration via, e.g., solvent extraction prior to introduction into the flame (SEFAAS) or to the newer technique of EAAS. The elements Na, K, Mg, Ca and Hg, although amenable to determination by EAAS are not listed in Table 5 as the flame provides adequate detectivity for the four macroelements, whereas the cold-vapour technique is clearly the one of choice for mercury. A good number of other elements in Table 5 can usually be determined in foods by flame spectrometry EAAS information for them is included, however, to cover the occasional sample with extremely low trace-element content. 

Minerals represent from 0.2-0.3% of the total intake of all nutrients in the diet. They are so potent and so important that without them the organism would not be able to utilize the remaining 99.7% of the food. The main mass of these minerals constitutes the macroelements the trace elements constitute only a hundredth of a percent of the total mass of daily eaten nutrients. Foods that are good sources of minerals are given in Table 4.1. 

A diet consisting of a variety of foods provides the best protection against potentially harmful chemicals in food. This is because the body tolerates very small quantities of many toxic substances, but has only a limited ability to cope with large quantities of any single one. Almost any chemical can have a harmful effect if taken in a large quantity. This is especially true for trace minerals, and to some degree, also for macroelements, as well as vitamins. For this reason, it is important to understand the difference between toxicity and hazard. Many foods contain toxic chemicals, but these chemicals do not present a hazard if consumed in allowable amounts. 

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