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Vitamin cobalt content

Laboratory-scale experiments which used L. casei symbiotically with Propionibacterium freudenreichii in the fermentation of whey gave an average yield of 2.2 mg of vitamin per liter the maximum was 4.3 mg/liter. Production of vitamin Bi2 is not species-specific. All species of Propionibacterium, when cultivated under the same conditions, produce active substances, but in different quantities. P freudenreichii and P zeae synthesized sufficient quantities to warrant their consideration for commercial exploitation. Because propionic acid bacteria are active during Swiss cheese ripening, it was anticipated, and actually demonstrated, that production of vitamin Bi2 in Swiss cheese is influenced by the same factors that influence its production in pure culture, particularly by the cobalt content of milk (Hargrove and Leviton 1955). [Pg.713]

The human body contains only about 1.5 mg of cobalt, almost all of it is in the form of cobalamin, vitamin B12. Ruminant animals, such as cattle and sheep, have a relatively high nutritional need for cobalt and in regions with a low soil cobalt content, such as Australia, cobalt deficiency in these animals is a serious problem. This need for cobalt largely reflects the high requirement of the microorganisms of the rumen (paunch) for vitamin B12. All bacteria require vitamin B12 but not all are able to synthesize it. For example, E. coli lacks one enzyme in the biosynthetic... [Pg.866]

Vitamin B12 (cyanocobalamin) can be determined by its cobalt content (4.35%) and given the low concentrations (0.2 pg cyanocobalamin per tablet has been reported [88]) and coloured solutions sometimes encountered, atomic absorption is a useful method for this determination. Care must obviously be taken if cobalt was used to prepare the vitamin, otherwise standard additions and a conventional air/acetylene flame can be used. If the concentration permits, the tablets may be dissolved in hot water, ethanol... [Pg.419]

The method of choice for the determination of most vitamins is HPLC due to its high separation capability, its mild analytical conditions, and the possibility to use various specifically adapted detection methods, e.g., LTV, fluorescence, or MS detection. All fat-soluble vitamins and most water-soluble vitamins have chromophores suitable for UV detection. Separation of vitamers and stereoisomers can be achieved. If a higher sensitivity is required HPLC with fluorescence detection can be used, either directly (e.g., vitamins A and E) or after derivatization (e.g., thiamine). A further improvement in sensitivity and specificity has been achieved by introducing HPLC with mass spectrometric detection in vitamin analysis. Due to the structural information retrievable, e.g., molecular mass, fragmentation pattern, this is the method of choice for analysis of samples with complex mixtures or low vitamin concentrations. Examples for the use of HPLC-MS in vitamin analysis include the determination of 25-hydroxy-D3 and pantothenic acid. However, one drawback of mass spectrometry is the need for an isotopically labeled reference compound for reliable quantification. Due to the structural complexity of many vitamins, these reference compounds are often expensive and difficult to synthesize. An interesting unique application is the determination of vitamin B12 by HPLC-IPC-MS, which is possible due to its cobalt content. [Pg.4898]

As shown previously (Vorobjeva and Iordan, 1976), the content of 2 pg vitamin Bn per g of dry biomass of P. shermanii represents a threshold for the isomerization to proceed. In these studies, a number of metabolic variables were investigated in vitamin Bn-replete cells (about 1000 pg vitamin B /g biomass), Bn-deficient cells (about 10 pg vitamin B /g biomass) and Bn-depleted cells (at most 2 pg vitamin Bn/g biomass). The cellular vitamin Bn content was varied by changing the concentration of a cobalt salt in the growth medium, or by using a mutant strain that produced only traces of corrinoids. [Pg.179]

By adding propionic acid bacteria to leavens bread can be enriched in vitamin B this is especially important for vegetarians and persons suffering from various diseases arising from vitamin B deficiency (see above). Vitamin Bn content in bacterial cells is regulated by the availability of cobaltous salts in the medium (see Chapter 5). Hence, tiie vitamin Bn content of bread can be modified by using an appropriate leaven. [Pg.232]

The total cobalt content of the body is 1-2 mg. Since it was discovered that vitamin B12 contains cobalt as its central atom, the nutritional importance of cobalt has been emphasized and it has been assigned the status of an essential element. Its requirement is met by normal nutrition. [Pg.426]

SOURCES OF COBALT. Cobalt is present in many foods. However, the element must be ingested in the form of vitamin B-12 in order to be of value to man hence, a table showing the cobalt content of human foods serves no... [Pg.211]

Cobalt— This mineral, which is an integral part of vitamin B-12—an essential factor in the formation of red blood cells, must be ingested in the form of vitamin B-12 in order to be of value to man hence, a table showing the cobalt content of human foods serves no useful purpose. The oigan meats (liver, kidney) are excellent sources of vitamin B-12 (hence, of cobalt). The vitamin B-12 content, in mcg/100 g, of some rich animal food sources follows beef liver. 111 clams, 98 lamb kidneys, 63 turkey liver, 48 and calf kidney, 25. [Pg.679]

The cobalt content of vitamin Bj2 is 4% by wei t. The total body content of cobalt is 1.1 mg. It is fo md in the liver, bone marrow and carots. The salts of cobalt are soluble in water so extra cobalt passes out along with urine. [Pg.83]

Co deficit Everywhere Low content of Co in Podsoluvisols, Podzols, Arenosols and Histosols. The average Co content in plant species is < 5 ppb The decrease of Co content in tissues decrease of vitamin BJ2 in liver (tr.—130 ppm), in tissue (tr.—0.05 ppm), in milk (tr.—3 ppm). Synthesis of vitamin Bi2 and protein is weakened. Cobalt-deficiency and Bj2 vitamin-deficiency. The number of animal diseases is decreasing in raw sheep —cattle — pigs and horses. Low meat and wool productivity and reproduction... [Pg.40]

Cu + Co deficit Especially in Swamp ecosystems Low content of Cu and Co in Podsoluvisols, Podzols, Arenosols and Histosols. Declining contents of Cu and Co in forage species (Cu from 3 to 0.7 ppm, Co < 5 ppb) Depressed synthesis of BJ2 vitamin and oxidation ferments. Cobalt-deficiency and B12 vitamin-deficiency complicated by Cu deficiency. The prevalent diseases of sheep and cattle... [Pg.40]

Sewage wastes contain as much as 4 ppm of vitamin Bi2 (Hoover et al. 1952B Miner and Wolnak 1953). Although frowned on for aesthetic reasons as a source of vitamin Bi2 for human nutrition, wastes from activated sludge processes may well provide the cheapest source for preparation of vitamin Bi2 concentrates used in cattle feed. Symbiotic growth of lactic and acetic acid bacteria has been recommended for producing sour milk products biologically enriched with vitamin Bi2 (Rykshina 1961). Acetic acid bacteria cultured in whey fortified with cobalt salts led to an 80-fold increase in vitamin B12. Propionic acid bacteria in skim milk supplemented with dimethylbenzimidazole increased the vitamin content by 300-fold. [Pg.713]

Royal jelly. Nutritional paste prepared by nurse bees tom head gland secretions and honey stomach contents for rearing queen bee larvae. R. j. contains ca. 24% water, 31% protein, 15% carbohydrates, 15% ether-soluble components as well as 2% ash, and further trace elements such as iron, manganese, nickel, cobalt, etc., and various vitamins. Although synthetically prepared R. j. keeps the larvae alive it does not result in the development of a queen bee. R. j. differs from the breeding nutrition of worker bees by having higher concentrations of neopterin, biopterin, and... [Pg.559]

Vitamin Bn-deficient cells contained about 30-45% less DNA than cells with physiological levels of the vitamin (Vorobjeva and Iordan, 1976 Iordan, 1992). The DNA content in these cells increased by up to 80% when AdoCbl was added to cultures growing in cobalt-ffee medium (Iordan et al., 1983) (Table 5.1). Strains with a potential capacity for high corrinoid synthesis demonstrated a more significant stimulation by exogenous AdoCbl than strains with low synthetic capacity (Fig. 5.7). However, P. acnes represented an exception to this rule it responded weakly to the addition of AdoCbl, despite having a high potential for vitamin Bn synthesis. [Pg.184]

Let us consider other natural habitats of propionic acid bacteria. In grasses used as fodder for livestock the content of cobalt is often below a certain limit (0.08 ppm), so that if cobaltous salts are not added to feeds, animals will suffer from cobalamin deficiency. Animals are supplied with corrinoids mainly through the biosynthetic activity of bacteria. If 1 mg of cobalt a day is added to the feed, then the content of cobalamins in the dry residue of lignin matter in rumen is 0.59 to 1.0 jag/g. When no cobalt is added, the content of cobalamins is lowered by an order of magnitude, to 0.081-0.108 ig/g (Smith and Marston, 1970) correspondingly, the content of vitamin in all animal tissues and fluids is low. Therefore, the concentration of vitamin in meat, milk and other products obtained from the animal will depend on the content of cobalt in the feed. [Pg.190]

Other natural habitats of propionic acid bacteria are represented by cheese and silage. If one recalls that there are at least 10 bacterial cells in 1 g of cheese, then it becomes clear that bacteria lead a cobalamin-deficient existence. The same is true of bacteria that live in silage, where the cobalamin content is about 0.1 to 2.0 xg per 100 g (Smith and Marston, 1970). In the rumen of ruminants, where cobalt is limited, the cobalamin content is in the range of 0.14-0.41 ng/ml (Dryden et al., 1962). It is clear that these bacteria live at a very low cobalamin level. Therefore, the conclusion is obvious—most propionic acid bacteria lead a vitamin B -deficient mode of life in nature, although they can readily attain high levels of corrinoids under favorable conditions. [Pg.190]

Livestock supplementation. Cobalt-deficient fodder such as grasses (contain less than 0.08 ppm) may cause serious losses of livestock and lead to vitamin Bn deficiency in humans consuming animal products. Farm animals utilize relatively small amounts of vitamin Bn, ranging from 0.05 to 0.5 mg per kg of their weight, but its content in animal feed is also very low. An effective utilization of the vitamin is due to the high affinity binding proteins. Low yields of cobalamins in the rumen of animals result from a relatively short period of bacterial transit and anaerobic conditions, unfavorable for the synthesis of the cobalamin precursor DMB. When DMB... [Pg.220]

Another preparation, Propiovit, is based on the cells of P. acnes isolated from cow s rumen, and this is an advantage over PABB. The preparation contains rumen bacteria grown in the medium containing glucose-protein concentrate (industrial waste), enzymatic hydrolysate of yeasts, ammonium sulfate, and cobaltous salt (Volkova, 1980). One g of dry preparation contains up to 5-10 living cells, B-group vitamins (pg/g) Bn, 400-500 pyridoxine, 33-51 nicotinic acid, up to 350 pantothenic acid, up to 330 riboflavin, 60-140 fohc acid, 3.2 water content less than 5-6%. [Pg.224]


See other pages where Vitamin cobalt content is mentioned: [Pg.372]    [Pg.387]    [Pg.33]    [Pg.144]    [Pg.825]    [Pg.830]    [Pg.609]    [Pg.179]    [Pg.107]    [Pg.234]    [Pg.682]    [Pg.454]    [Pg.457]    [Pg.458]    [Pg.165]    [Pg.36]    [Pg.1365]    [Pg.48]    [Pg.320]    [Pg.312]    [Pg.334]    [Pg.190]    [Pg.732]    [Pg.731]   
See also in sourсe #XX -- [ Pg.320 ]




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Vitamin content

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