Phytic acid bodies

The aleurone layer differentiates from the rest of the starchy endosperm approximately 2 weeks after pollination. There is clear evidence that aleurone cells synthesize starch granules after fertilization however, the starch granules disappear and the cell walls thicken as the grain matures. The cytoplasm of aleurone cells contains phytic acid bodies, protein bodies, and spherosomes or fat depots. The aleurone ceU walls contain soluble and insoluble dietary fiber, phenolics such as ferulic acid, ara-binoxylans, and P-glucans that fluoresce when viewed under a microscope equipped with ultraviolet light. 

Phosphate is better used when supplied by food than when supplied by phosphate salts, such as potassium phosphate. The food phosphate occurs largely as phosphate esters and, with gradual hydrolysis, enters the body relatively slowly and is used efficiently in the metabolic processes. Phosphate supplied as inorganic phosphate is rapidly absorbed, with a tendency to be excreted in the urine rather than to be used by tissues (Schuette and Linkswilcr, 1962). The phosphate in bran occurs largely in the form of phytic acid (inositol hexaphosphate). The phosphate groups of fhis compound may be only partially hydrolyzed in the gut- Phytic acid tends to be excreted via the fecal route as a complex with iron or calcium. 

If one had to state an overall role of copper in the body, one might say oxygen metabolism. One major factor shared by both zinc and copper is that both metal ions occur bound to metallothionein. The function of metallothionein is not firmly established. Copper is bound to another protein, ceruloplasmin, which occurs in the cell and plasma. The function of this protein is not clear either. Zinc absorption, as iron absorption, is impaired by high levels of phytic acid. Copper absorption is not inhibited by phytic acid. The major route of excretion of both metal ions is fecal, rather than urinary. 

As already described for phytic acid, also adding amino acids to feed has an economical as well as an ecological impact. The most relevant feed plants are soy and corn. Their profile of essential amino acids - and that of other plant materials as well - does not meet exactly the livestock s essential amino acid demand profile. Since the animals eat feed-protein until the demand of the most limited amino acid is filled the remaining overflow of other amino acids cannot be transformed into body mass. It is excreted. Consequently liquid manure of... 

The fact that phytic acid P is not completely available to the body, even in absence of calcium in the diet, was established by Lowe and Steenbock (1936). Increased Ca in the diet depresses phytic acid digestion considerably in the rat. Harrison and Mellanby (1939) observed that the mineralization of bones in puppies suffered as the result of the addition of phytic acid to the diet, and the explanation that phytic acid depresses the... 

In his Natural History (1826), Pliny the Elder stated that those persons who are dieted npon fermented bread are stronger in body , which is an early statement on the health benefits of sourdough breads. Whole meals of cereals are a good source of minerals. Their bioavailability is limited, as they are often bound to phytic acid (myo-inositol-hexophospate). Wheat and rye contain about 1.2% of dry matter (Fretzdorff Briimmer, 1992). With the drop in pH during sourdough fermentation, endogenous phytases of the cereals are activated and the bound minerals are released (Fretzdorff Briimmer, 1992). Lactic acid bacteria and yeasts also possess phytase... 

The residual oil of the cake or meal is highly unsaturated and may result in soft body and milk fat if consumed in excessive amounts and may also impart a disagreeable flavour to milk. The oil rapidly becomes rancid and unpalatable, and meals containing it have been implicated in cases of vitamin E deficiency. The meal has a high content of phytic acid, which makes much of its phosphorus unavailable rations containing the meal may also need extra supplementation with calcium. 

Phytin, the insoluble mixed potassium, magnesium and calcium salt of myoinositol hexaphosphoric acid (phytic acid) is the major storage form of phosphate and macronutrient mineral elements in seeds. It is invariably present within a globoid in protein bodies [38, 45, 47, 56, 68, 69, 71]. 

Cereal grains contain high levels of phytic acid. Why is phytic acid an inhibitor of iron uptake by the human body ... 

The addition of phytic acid to white flour markedly reduced the absorption of these minerals in short-term studies. With prolonged ingestion, the body can adapt to a high phytate intake apparently as a result of the action of enzymes which release the phosphate from soluble phytates. Phytases may be derived from the food, the digestive secretions or the intestinal bacteria. 

The recommended daily dietary doses of copper are 0.4-0.7 mg for children under 1 year, 0.7-2.0 mg for children aged 1 to 10 years, 1.5-2.5 mg for adolescents and 1.5-3.0 mg for adults. Resorption of copper and its retention in the body depend on the chemical form in which this element is present in the diet. Experiments on laboratory animals have shown a higher utilisation of copper in the form of neutral and anionic complexes contained in plant material than in the form of copper sulfate. Availability of copper increases the presence of proteins and amino acids in the diet. Also, carboxylic and hydroxycarboxylic acids stimulate resorption of copper. In contrast, higher doses of ascorbic acid, fructose, molybdenum, sulfur compounds and zinc significantly reduce the resorption of copper. Ascorbic acid reduces cupric compounds to slightly soluble cuprous compounds. The effect of phytic acid and dietary fibre on copper resorption is, in comparison with the effect of these components in zinc, less pronounced. 

ABSORPTION, METABOLISM, EXCRETION. Zinc is poorly absorbed less than 10% of dietary zinc is taken into the body, primarily in the duodenum. It appears that metallic zinc and zinc in its carbonate, sulfate, and oxide forms are all absorbed equally well. Large amounts of calcium, phytic acid, or copper inhibit zinc absorption. Cadmium appears to be a zinc antimetabolite. 

B-vitamins, minerals, phytic acid (phytic bodies), proteins (protein bodies), and phenolic compounds. 

Most phosphorus associated with cereal grains exists in the form of phytic acid (myoinositol hexaphosphate) that is stored in phytic bodies mainly loeated in the aleurone layer. These molecules bind potassium, magnesium, and other minerals. The phytases degrade these compounds to release phosphate, other minerals, and myoinositol. The myoinositol is a known precursor of sugars associated with cell wall polysaccharides and a promoter of seedling growth. The free phosphorus is critically important for synthesis of nucleic acids and phospholipids for cellular membrane proliferation, and ATP and energy production. 

Phytic bodies Organelles that store phytic acids. In cereals, most phytic bodies are in the aluerone cells. 

Treatment of other areas of the body with AHAs is not often described, because of the poor penetration of these acids through the skin of the body. A technique combining abrasion and an application of Easy Phytic solution (see Chapter 11) is more successful on the legs, arms and torso. 

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