Nutrient requirements Pyridoxine

Various species and strains of Streptococcus (see Table IX) require pyridoxin as an essential nutrient. The nutrient requirements of these organisms are complex, and other essential metabolites besides pyridoxin must be given them. Here it is worth stressing that, just as the requirement for a given essential metabolite as a nutrient is conditional on the rate of synthesis of this substance by the cells, so too there may be considerable interdependence in requirements for different essential metabolites, because of the general interlinking of metabolic processes in the cells. Thus a nutritional requirement for a given essential metabolite may be conditional not only on its rate of synthesis but also on the rate of synthesis of another essential metabolite. 

Several lower fungi have already been found to require pyridoxin for growth, while in. some groups related organisms have not required it as a nutrient, probably being able to synthesize it for themselves. 

Folic acid/cobalamin/pyridoxine hydrochloride are nutritional combinations. Folic acid and cobalamin reduce homocysteine by metabolizing it to methionine. Pyridox-ine facilitates breakdown of homocysteine to cysteine and other by-products. They are indicated for nutritional requirement of patients with end-stage renal failure, dialysis, hyperhomocysteinemia, homocystinuria, nutrient malabsorption or inadequate dietary intake, particularly for patients with or at risk for cardiovascular disease, cerebrovascular disease, peripheral vascular disease, arteriosclerotic... 

At higher ethanol concentrations the intracellular alcohol interferes with membrane organization, increasing its fluidity and permeability to ions and small metabolites and inhibiting transport of nutrients. Especially Ca and Mg ions are able to increase the plasma membrane stability. It has been demonstrated that incorporation of unsaturated fatty acids and/or sterol(s) as well as proteolipids into cellular membrane of yeasts helps to alleviate ethanol tolerance. For the synthesis of the unsaturated fatty acids the presence of traces of oxygen under fermentation conditions is required. Further to Ca and Mg ions, other trace elements such as Co, Cu, Mn and Zn " and vitamins, e.g. pantothenate, thiamine, riboflavin, nicotinic acid, pyridoxine, biotin, folic acid and inositol, are essential for the growth and ethanol production by yeasts. 

Ascorbic acid differs from the other vitamins in that it is required in the diet by only a few species of animals—man, other primates, the guinea pig, an Indian fruit-eating bat, and the red-vented bulbul and some related species of Pas-seriform birds. Other species of animals synthesize ascorbic acid. All mammals and other larger animals require vitamin A, thiamine, riboflavin, nicotinic acid, and pyridoxine as essential nutrients, although microoi anisms usually have the power to synthesize all or most of these substances. 

Vitamins, minerals, and electrolytes— Studies have shown that during moderate to severe stresses, more zinc, copper, magnesium, and calcium are lost in the urine. Furthermore, stress results in altered blood levels of vitamins A and C, and of zinc and iron. Also, part of the response to stress includes water and sodium retention, via veisopressin and aldosterone secretion. As for the water-soluble vitamins—thiamin, riboflavin, niacin, pyridoxine (B-6), pantothenic acid, folic acid, and vitamin C stress increases their requirement. However, no dietary recommendations are made for these nutrients for individuals under stressful situations. Still, it seems wise to supply some supplementation before deficiency symptoms appear. 

Pyridoxin synthesized E ssential nutrient or different nutrient conditions required for synthesis... 

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