Pantothenic acid nutritional requirement

The requirement of pyridoxal phosphate for heme synthesis was first shown by a nutritional experiment. In 1950 Wintrobe [47] found that pigs deficient in vitamin Bg formed small, pale, red cells very low in free protoporphyrin, stored excessive iron, and had a h3q)erplastic bone marrow. Lascelles [8] showed that both vitamin Bg and pantothenic acid were required for porphyrin synthesis in Tetrahymena vorax. Similarly, studies by Schulman and Richert [48] showed that heme synthesis in deficient ducklings required vitamin Bg and CoA. 

It is apparent that at this stage of development definitive conclusions are premature, and that this aspect of amino acid and lipide metabolism will be pursued vigorously in the near future. It is of considerable interest to us that biotin and pantothenic acid deficiencies affect amino acid transport in L. arabinosus, since both vitamins are known to play a prominent role in lipide biosynthesis. We are currently reexamining the turnover of lipide fractions in nutritionally normal and vitamin-deficient cell types to determine whether there is some relation between this aspect of metabolism and amino acid transport. In any case, the nature of the catalytic steps involved in amino acid transport is still unknown to us. They probably occur in the peripheral cell membrane, but even this elementary and widely accepted belief will require additional study before it can be accepted beyond doubt as an established fact. 

R)-Pantothenic acid (vitamin B5) is synthesized by microbes and plants, but not by mammals, who require it as a nutritional factor. Only the (R)-enantiomer is physiologically active. (R)-Pantothenic acid is produced as its calcium salt on a 6 kt a-1 scale, 80% of which is applied as an animal feed additive major suppliers are Roche, Fuji and BASF. Pantothenic acid is produced via chemical methods [110] but a fermentative procedure has recently been commercialized. 

Pietrzik K, Hesse CH, Zur Wiesch ES, and Hotzel D (1975) Urinary excretion of pantothenic acid as a measurement of nutritionai requirements. International Journal of Vitamin and Nutrition Research 45, 153-62. 

In the investigation of vitamin deficiencies, it is well to bear in mind that diets deficient in a rangle vitamin produce metabolic disorders which alter the animal s requirement for other nutritional factors. Where pantothenic acid deficiency is concerned, there is evidence that the metabolism of ascorbic acid, biotin, protein, carbohydrate, and fat are involved. 

It is true that when the selenium and/or methionine in the diet is suboptimum, there is a marked increase in the requirement for vitamin E. However, many stresses and other nutritional deficiencies are also known to increase the tocopherol requirement. For example, carbon tetrachloride toxicity, protein, B12 and folic acid deficiencies (Hove and Hardin, 1951a,b), and Be deficiency (Day and Dinning, 1956), all increase the requirement for a-tocopherol. As for the relationship of ubiquinone to tocopherol, here also, one wonders whether the decreased amount of ubiquinone found in vitamin E deficiency is specific or an incidental effect of one form of inanition, since a deficiency of pantothenic acid, and possibly other deficiencies that affect liver function, will produce similar decreases in ubiquinone. 

Lactic acid bacteria have very limited biosynthetic capabilities and, reflecting this, are described as nutritionally fastidious. Early work by Du Plessis (1963) noted that all strains of wine lactic acid bacteria required nicotinic acid, riboflavin, pantothenic acid, and either thiamine or pyridoxine. 

However, nitrogen is not the only nutritional factor that influences H2S evolution in grape musts as evidenced by Sea et al. (1998) who reported poor correlations between H2S and must nitrogen concentrations. Metabolic depletion of OAS and OAH could be the result of a lack of pantothenic acid, a vitamin required for the synthesis of coenzyme A (GoA), which is necessary for formation of these precursors (Fig. 1.12). In agreement, pantothenic acid deficiency is known to increase H2S pro-... 

From a nutritional standpoint, it is significant that five of the B-complex vitamins (riboflavin, nicotinamide, thiamine, vitamin Be, and pantothenic acid) have been shown to be constituents of the coenzymes. The nutritional requirement of these vitamins is explained on the basis of their coenzyme function. In all cases the coenzyme form appears to be the sole bound form of the vitamin, and this then becomes the only metabolically active form for these particular vitamins. 

Although pantothenic acid and coenzyme A are undoubtedly important in nutrition in man as well as in animals, no evidence of human pantothenic acid deficiency has been recorded. The wide distribution of pantothenic acid in food may explain this failure to observe deficiency even on restricted diets. The human requirement is unknown but probably is not above 5 mg. dailyIn dogs, the need is similar to that for thiamine and ribofiavin. 

The role of pantothenic acid in human nutrition has not been established. It is of wide natural occurrence, as the name implies. Metabol-ically, pantothenic acid seems to have some special role in the adrenals, and this may be a link with acetylation mechanisms in the synthesis of steroids (Hughes, 1953). The burning feet" syndrome encountered in prisoners of war and other malnourished groups has been specifically treated with pantothenic acid (Gopalan, 1946). The figures given by Williams et al. (1950) for B vitamins in different foods and tissues can be considered to show a ratio of pantothenic acid to thiamine, riboflavin, and niacin at an amount about half that of the niacin, but ten times the thiamine. No precise requirement can be stated. 

These are nutrients that are present in the body, and required by the body in minute quantities, ranging from millionths of a gram (microgram) to thousandths of a gram (milligram). Examples are vitamin B-12, pantothenic acid, chromium, cobalt, copper, fluorine, iodine, iron, manganese, molybdenum, selenium, silicon, and zinc. Their minuteness in no way diminishes their importance to human nutrition-many are known to be absolutely essential. 

RECOMMENDED DAILY ALLOWANCE. The amount of pantothenic acid required by human beings has not been determined so, a recommended daily allowance for pantothenic acid has not been made by the Food and Nutrition Board of the National Research Council. Nevertheless, they do give "estimated safe and adequate intakes" beised on proportional energy needs (see section on VITAMIN(S), Table V-5, Vitamin Table). Further, they suggest that a higher intake may be needed during pregnancy and lactation. 

Table XII records a group of bacteria for which pantothenic acid itself has been found to be an essential nutrient. In reading Table XII, it must always be borne in mind that the findings refer only to the actual cultures examined. It is not permissible to generalize and to conclude that all strains under a given specific name will have the same nutritional requirements. The nutritional requirements are always relative to the synthesizing ability of the cells of the inoculum, and this may differ from strain to strain within a species, or even from culture to culture of the same strain, depending on the cultural conditions, including the presence of other growth factors.

Leonian and Lilly (201) compared the relative requirements of 10 different strains of yeast for biotin, thiamin, inositol, pantothenic acid, and pyr idoxin, using 72 hour growth. No strain grew significantly without biotin, all were restricted without pantothenic acid, one was dependent upon thiamin, etc. Again inter-relations in growth effect were observed and, in general, it could not be said that the nutritional need for any one substance was absolute specific requirements depended on the presence of the other substances. 

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