[27] Radioassay of vitamin B12 and other corrinoids

Pratt, John J.; Woldring, Mg

doi:10.1016/0076-6879(82)84029-9

Cited by 5 publications

(3 citation statements)

References 123 publications

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“…The reduced cell-free liquid from the propanediol culture did not degrade CT (Figure 1a), which indicates that there was not a significant level of extracellular agents in the fermentative culture that promote CT degradation. The measured vitamin B12 in the liquid was very low at 0.30 µg/L, close to the background level of some natural waters (28). There was significant CT degradation in the autoclaved control bottles with the propanediol culture.…”

Section: Resultssupporting

confidence: 58%

Carbon Tetrachloride Degradation: Effect of Microbial Growth Substrate and Vitamin B₁₂ Content

Zou

Stensel

Ferguson

2000

Environ. Sci. Technol.

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Microbial degradation kinetics of carbon tetrachloride (CT) under reducing conditions were investigated for different cultures, fed with 1,2-propanediol, dextrose, propionaldehyde, or acetate and nitrate, in the anaerobic step of an anaerobic/aerobic operation sequence. Methanogenesis was inhibited due to the aerobic step. CT biodegradation rates followed first-order kinetics with respect to CT concentration and biomass and were not affected by the presence of growth substrate. CT degradation rates increased linearly with higher intracellular vitamin B12 content. The culture fed 1,2-propanediol had the highest vitamin B12 content, which was 3.8, 4.7, and 16 times that of the propionaldehyde-, dextrose-, and acetate-fed cultures, respectively, and its first-order degradation rate constant was 2.8, 4.5, 6.0 times that for those cultures, respectively. No CT degradation occurred with culture liquid, suggesting that intracellular factors were responsible for CT degradation. The propanediol culture was able to sustain a constant CT degradation rate for a 16-day test period without substrate addition. Compared to a propanediol-fed culture grown only under anaerobic conditions, the propanediol culture grown under the sequential anaerobic/aerobic condition resulted in more biomass growth and a greater CT degradation rate per unit of propanediol fed, although its CT degradation rate per unit of biomass was lower.

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Section: Resultssupporting

confidence: 58%

Carbon Tetrachloride Degradation: Effect of Microbial Growth Substrate and Vitamin B₁₂ Content

Zou

Stensel

Ferguson

2000

Environ. Sci. Technol.

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“…0.2 to 0.4 g fresh weight) were frozen in liquid nitrogen and were either used immediately for vitamin analysis or were stored at -40°C until analyzed. Vitamin analysis was performed by the Radioisotope Dilution (RID) technique (Oersterdahl et al, 1986;Pratt and Woldring, 1982). Frozen plant materials were crushed and then homogenized at root temperature with 20 to 40 mL acetate buffer (0.4 mol L 1, pH = 4.6 and containing 3mmol L -1 KCN) as described by Oesterdahl et al (1986).…”

Section: Generalmentioning

confidence: 99%

“…After centrifugation, the supernatant liquid was then counted with a Gammazint BF 5300 gamma counter. The concentrations of B12 in unknown samples are read from a standard curve, derived by plotting the amount of 57Co-vitamin B12 bound to the Intrinsic Factor in the presence of known concentrations of cyanocobalamin (Pratt and Woldring, 1982) and expressed on the fresh weight basis of plant tissues.…”

Section: Generalmentioning

confidence: 99%

Uptake of a microbially-produced vitamin (B12) by soybean roots

Mozafar¹,

Oertli²

1992

Plant Soil

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Vitamin B12 (Cyanocobalamin) is one of the vitamins believed to be produced exclusively by microorganisms. Although soil is a rich source of vitamin B12, systematic study as to possible uptake of this vitamin by the plant roots is lacking. This study was undertaken to investigate, under water culture conditions, the uptake of [57Co]-cyanocobalamin by soybean (Glycine max (L.) Merr.). In the range of 10 to 3200/zmol L-~, uptake of vitamin B12 was a linear function of the vitamin concentration in the nutrient solution. Depending on the vitamin concentration, 12 to 34% of the total absorbed vitamin was transported to the plant shoots, with proportionally more vitamin B12 transported at higher vitamin concentrations. Aeration of the rooting medium with nitrogen gas significantly increased the total uptake and the percentage of vitamin transported to the shoots. Addition of respiration inhibitor dinitrophenol to the nutrient solution did not affect the total uptake or the partitioning of the vitamin. Root temperature (5-30°C) did not affect the total uptake but significantly altered the partitioning of the vitamin between the roots and the shoots. Foliar-applied vitamin B12 was not translocated to any considerable degree to other plant parts, indicating that phloem transport does not contribute to the distribution of this vitamin within the plant. It is suggested that adding manure (which is rich in this vitamin) to the soil could increase soil and thus plant content of vitamin B12. This could be of importance in raising the intake of this vitamin by people living by choice or necessity on vegetarian diets who are usually threatened by vitamin B12 deficiency.

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Development of a specific radioimmunoassay for vitamin B12 and its application in the diagnosis of cobalt deficiency in sheep

Kennedy

O’Harte

Blanchflower

et al. 1990

Veterinary Research Communications

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[27] Radioassay of vitamin B12 and other corrinoids

Cited by 5 publications

References 123 publications

Carbon Tetrachloride Degradation: Effect of Microbial Growth Substrate and Vitamin B₁₂ Content

Carbon Tetrachloride Degradation: Effect of Microbial Growth Substrate and Vitamin B₁₂ Content

Uptake of a microbially-produced vitamin (B12) by soybean roots

Development of a specific radioimmunoassay for vitamin B12 and its application in the diagnosis of cobalt deficiency in sheep

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[27] Radioassay of vitamin B12 and other corrinoids

Cited by 5 publications

References 123 publications

Carbon Tetrachloride Degradation: Effect of Microbial Growth Substrate and Vitamin B12 Content

Carbon Tetrachloride Degradation: Effect of Microbial Growth Substrate and Vitamin B12 Content

Uptake of a microbially-produced vitamin (B12) by soybean roots

Development of a specific radioimmunoassay for vitamin B12 and its application in the diagnosis of cobalt deficiency in sheep

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Product

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Carbon Tetrachloride Degradation: Effect of Microbial Growth Substrate and Vitamin B₁₂ Content

Carbon Tetrachloride Degradation: Effect of Microbial Growth Substrate and Vitamin B₁₂ Content