Riboflavin Values Research Articles

Tiamina e riboflavina: evolução com a maturação de Cabernet Sauvignon e comportamento durante a fermentação com diferentes níveis de anidrido sulfuroso adicionado

O objetivo do trabalho foi estudar o comportamento das vitaminas,tiamina (vitamina B1) e riboflavina (vitamina B2),durante a maturação de Vitis vinifera cultivar Cabemet Sauvignon e durante a fermentação do mosto, usando diferentes quantidades de SO2. Os valores mínimos encontrados para tiamina e riboflavina foram respectivamente (ug/100nd): 7,67 e 6,85 com 5,5 °Brix e os máximos foram, respectivamente, 19,35 (na colheita) e 15,75 com 12,8 °Brix. A tiamina foi quase totalmente consumida antes da fermentação inicial, aparecendo novamente ao final da mesma. A riboflavina, ao contrário aumentou durante a fermentação. Ambas as vitaminas aumentaram durante a maturação de Cabemet Sauvignon, estando a tiamina presente em maior quantidade. O aumento das quantidades de SO2 adicionado ao mosto, afetou a tiamina numa proporção direta, mas não teve nenhum efeito sobre a riboflavina. A tiamina diminuiu durante a fermentação, ao mesmo tempo em que ocorreu um aumento da riboflavina.

Nutrient composition of four cuts of British Columbia grainfed veal

The objective of this study was to determine the nutrient content of four cuts of BC grainfed veal. Rib chops, loin chops, rolled shoulder roasts and shanks were evaluated for proximate composition, cholesterol, eight minerals, thiamin, niacin and riboflavin. Both raw and cooked samples were examined as lean meat only and as total edible portion (lean plus fat). Nine samples were purchased for each treatment, homogenized, combined, and analyzed in triplicate. Results of nutrient analysis showed significant differences from US Department of Agriculture data. Raw and cooked lean-only and total edible samples were found to be lower in fat, sodium and niacin but higher in iron, potassium and copper. Phosphorus levels were lower in some but not all cuts, as were calcium levels. Thiamin levels were higher in some cuts. Values for moisture, ash, protein, cholesterol, zinc, magnesium and riboflavin were comparable to the U.S. data. Key words: Veal, Canadian veal, grainfed veal, nutrient composition

Riboflavin 5′-pyrophosphate: A contaminant of commercial FAD, a coenzyme for FAD-dependent oxidases, and an inhibitor of FAD synthetase

Commercially available preparations of flavin adenine dinucleotide (FAD) have been found to be 94% pure, the remaining 6% being composed of four or five minor contaminants which can be separated from FAD by reverse-phase high-performance liquid chromatography. FAD purified in this manner has been shown to be 100% pure. One of the contaminants has been identified as riboflavin 5′-pyrophosphate (RPP) by spectroscopic and chemical methods of analysis. This compound has been shown to exhibit biological activity as a weak cofactor for two FAD-requiring enzymes. With the apo-protein of porcine d-amino-acid oxidase, values determined for RPP were 8.4 μ m for K m and 0.10 for V max compared to 0.47 μ m and 0.28 (36 U/mg), respectively, for FAD. With fungal glucose apooxidase, values determined for RPP were 474 n m for K m and 0.02 for V max and 45 n m and 0.09 (105 U/mg), respectively, for FAD. RPP can also inhibit FAD biosynthesis. For bovine liver FAD synthetase, a K i value for RPP against FMN was determined to be 9 μ m where K m for FMN was 5.5 μ m. These studies illustrate the value of riboflavin 5′-pyrophosphate as a flavin analog for use in the study of structure/function relationships within certain flavin-dependent enzymes.

Nutritional Status of Free-Living Alzheimer’s Patients

Self-reported, dietary intake and biochemical estimates of thiamine, riboflavin, folate, vitamin B-12, protein, and iron were compared in 22, free-living elders by individuals who had senile dementia of the Alzheimer's type (SDAT) and in 41 who were cognitively normal (CN). The two groups did not differ significantly in their intake of these nutrients or the number of deficiency states for intake (less than 67% RDA). Low serum transketolase (thiamin; p less than 0.055), red blood cell (RBC) folate (p less than 0.06), and serum vitamin B-12 (p less than 0.05) levels occurred more often in SDAT patients than in CN subjects. Individuals in both groups who used multivitamin supplements had significantly higher biochemical values for thiamine (p less than 0.03), riboflavin (p less than 0.01), and vitamin B-12 (p less than 0.003) than nonsupplement users. Because of the differences in vitamin B-12 and RBC folate levels between groups, a retrospective analysis was performed on a larger group of subjects drawn from a geriatric assessment clinic. Patients with SDAT had significantly lower serum vitamin B-12 (p less than 0.01) and lower RBC folate (p less than 0.03) values than CN subjects. Which mean values for vitamin B-12 and RBC folate were grouped by degree of impairment in SDAT subjects, vitamin B-12 was significantly lower in mildly and moderately impaired subjects than in those with normal cognition. Mean values for both nutrients did not differ significantly between severely impaired and CN subjects. There was a significant quadratic relationship between cognitive impairment and biochemical values for vitamin B-12.(ABSTRACT TRUNCATED AT 250 WORDS)

Riboflavin excretion from roots of iron‐stressed and reciprocally grafted tobacco and tomato plants

Abstract Seedlings of tomato and tobacco were V‐grafted reciprocally and intraspecifically and cultured for 22 days in 2‐liter containers of nutrient solution with normal or no iron. The pH of solutions containing iron increased slightly, while the pH of solutions with no iron decreased. There was little decrease in the pH of tomato grafts on tomato, while the pH of other combinations decreased from 1.5 to 3.1 pH units. Riboflavin concentrations in nutrient solution were highest with tobacco on tobacco, and were about one‐third less with tomato on tobacco. The riboflavin values for tobacco on tomato and tomato on tomato were barely detectable like those for plants supplied with iron. Roots of iron‐deficient tobacco plants at harvest contained much more total riboflavin than roots of iron‐deficient tomato plants and roots of iron‐supplied plants contained less total riboflavin than iron‐deficient plants. Total riboflavin in roots of tobacco plants exceeded that in roots of tomato plants. The total riboflav...

Nutrient content of liquid milk

SummaryConcentrations were measured of different vitamins in milk as delivered to the home and after storage in the domestic refrigerator, during summer and winter periods. Vitamin C concentrations varied greatly, ranging from 0·1 to 18·4 εg/ml. Most of the lower vitamin C values were associated with known exposure of the milk to daylight and there was a clear tendency for the concentrations to fall with increased time of refrigerated storage especially when associated with prior exposure of the milk to daylight. Riboflavin values were mostly in the range 1·35–1·92εg/ml, but occasional lower values were associated with low content of vitamin C and in some instances with prolonged exposure to daylight on the doorstep. Concentrations of the other vitamins (εg/m1) were: folic acid 0·041–0·074, thiamin 0·38–0·48, vitamin B12 0·0032–0·0044 and vitamin B6 0·56–0·71. All fell within the normal ranges and were not significantly influenced by exposure of the milk to daylight or subsequent storage in the refrigerator.

Effect of Sex and Age on Proximate Analysis, Cholesterol and Selected Vitamins in Broiler Breast Meat

Breast meat was obtained from 7- through 12-wk-old commercially reared broilers and analyzed. Proximate analyses values showed no differences due to sex or age of bird. Riboflavin values remained constant at about 0.09 mg/100g raw flesh for the period studied. Vitamin B6 values were higher than has been reported in literature (0.72-0.86 mg/100g range). Niacin values were only slightly higher than previously reported (11.7-13.3 mg/100g). Cholesterol values were lower than reported in the literature (31-54 mg/100g vs 58 mg/100g). The 7- and 12-wk values were near reported values, while the 9, 10 and 11-wk values were definitely lower.

The modeled structure of the IgG Gar VL region and its implications for anti-flavin and anti-DNP fine specificities.

The variable domain (V) sequence of the lambda-light chain of the Gar IgG2 human myeloma protein was determined from enzymatically generated peptides that were isolated, characterized, and ordered by overlap and/or by subgroup homology. The sequence consisted of the amino terminal 107 residues of the light chain, and shared subgroup V lambda III-specific residues as well as a pattern of CDR deletions unique to most V lambda III sequences. The structural role of the light V region in the high affinity for flavins and the low affinity for 2,4-dinitrophenyl haptens characteristic of the intact IgG molecule was coarsely assessed by way of model building and by comparison with the refined combining site model of MOPC 315, an Ig with relative affinity values for DNP and riboflavin the converse of those observed in Gar.

Nitrate reductase from Penicillium chrysogenum: The reduced flavin-adenine dinucleotide-dependent reaction

Nitrate reductase from Penicillium chrysogenum catalyzes the FADH 2-dependent reduction of nitrate in the absence of excess dithionite. At pH 7.2 (0.1 m potassium phosphate buffer) the FADH 2/nitrate reciprocal plot patterns were parallel. Nitrite was competitive with nitrate and an uncompetitive inhibitor with respect to FADH 2. FAD was competitive with FADH 2 and uncompetitive with nitrate. FMNH 2 and riboflavin H 2 also served as reducing agents and yielded the same kinetic patterns. The results are consistent with a nonclassical, two-site model in which nitrate and nitrite bind to a site different from the site at which FADH 2 and FAD bind. The following results suggest that the site at which FADH 2 binds to reduce the enzyme (and at which FAD binds in competition with FADH 2 to inhibit the reaction) is not the same high-affinity site to which FAD binds as a cosubstrate in the NADPH + FAD-dependent reaction: (a) The K m for FAD in the NADPH + FAD-dependent reaction at pH 7.2 is only 0.17 μ m, while the K i , for FAD in the FADH 2-dependent reaction is 65 μ m. (b) FAD is the preferred flavin in the NADPH + oxidized flavin-dependent reaction. (The K m values for FMN and riboflavin are 15 and 41 μ m, respectively.) But all three oxidized flavins have about the same K i in the reduced flavin-dependent reaction (65, 80, and 165 μ m, respectively). Furthermore, (c) the K m values for FADH 2, FMNH 2, and riboflavinH 2 in the reduced flavin-dependent reaction are all about the same (ca. 900 μM), (d) V values (specific activities in units per milligram of protein) of the NADPH + oxidized flavin-dependent reaction in 0.1 m phosphate, pH 7.2, are in the order FAD (225) > FMN (150) > riboflavin (60), but the values in the reduced flavin-dependent reaction are in the order FADH 2 (100) < FMNH 2 (150) < riboflavinH 2 (500). Dithionite is known to reduce the cytochrome b component of nitrate reductase. But in the absence of a flavin, the specific activity of the dithionite-dependent reaction is only about 7—extremely low compared to the range of 60–500 for the nucleotide-dependent reactions. This result, together with the intersecting FAD/nitrate reciprocal plot patterns, suggests two possible models for the NADPH + FAD-dependent reactions: (a) FAD binds to two different high-affinity sites. At the “upstream” site, FAD mediates the transfer of electrons from NADPH to the cytochrome b prosthetic group. At the “downstream” site FAD plays either an additional electron transfer role or an activator role promoting the flow of electrons to nitrate. (b) There is only one high-affinity FAD site. FAD must occupy this site (even after the cytochrome is reduced) in order for electrons to flow to nitrate.

Nutritional status of African populations predisposed to esophageal cancer.

Nutritional status indicators were assessed chemically in blood and urine taken from 625 Transkeians drawn from three age-groups in each of two regions: one with a moderate risk for esophageal cancer and one with a very high risk. Aggregate mean values for protein, albumin, vitamin A, and phosphorus were generally acceptable, but many subjects had inadequate (though not necessarily deficient) values for nicotinic acid (74% of subjects), magnesium (60%), vitamin C (55%), carotene (53%), riboflavin (41%), calcium (35%), and zinc (27%). Groups at highest risk for esophageal cancer had markedly lower serum magnesium and carotene concentrations and mildly depressed hemoglobin and hematocrit values, but such findings are not necessarily associated with esophageal cancer etiology. Possible intestinal malabsorption in the populations at highest risk may be associated with the unusually high fiber and phytate intake of the high-risk populations as well as with exposure to necrotizing mycotoxins. Thus, while protein and energy nutriture seem generally adequate, both the high- and moderate-risk populations had high incidences of multiple micronutrient malnutrition.

The effect of thiamin and riboflavin supplementation on the level of those vitamins in human breast milk and urine

Thiamin and riboflavin concentrations in urine and breast milk were measured to see if vitamin supplementation during lactation is beneficial to healthy well-nourished women. seven supplemented subjects and five nonsupplemented subjects expressed milk four times per day for 3 days at 1 and 6 weeks postpartum. Dietary intakes were recorded for 1 day before milk collection and the 3 days of milk collection. A 24-hr urine sample was collected at 1 and 6 weeks postpartum. Mean thiamin concentration in the milk increased significantly in both groups between 1 and 6 weeks postpartum, although there were no significant differences between groups. Riboflavin values reflected in the milk were significantly lower in the nonsupplemented group of women both at 1 and 6 weeks postpartum, but values did not change significantly in either groups as the milk matured from 1 to 6 weeks postpartum. Urinary excretion of thiamin and riboflavin was proportionally higher in the supplemented group of women. Riboflavin and thiamin status of both groups of women depicted normal intakes and the milk concentration of thiamin and riboflavin either met or exceeded established norms in both groups of women.

A continuous fluorometric assay for flavokinase Properties of flavokinase from Peptostreptococcus elsdenii

A continuous fluorometric assay that utilizes apoflavodoxin as a trapping agent for riboflavin 5′-phosphate (FMN) has been developed for flavokinase (ATP:riboflavin 5′-phosphotransferase, EC 2.7.1.26). Use of this assay is illustrated in a procedure for the partial purification of flavokinase from the strict anaerobe Peptostreptococcus esldenii. The purified enzyme catalyzed the formation of 8.3 nmol FMN · min −1 at 37°C and had apparent K m values for riboflavin and ATP of 10 and 4.7 μM, respectively. ATP could be replaced by ADP (22% of the rate observed with ATP) but not by GTP. The enzyme also phosphorylated 5-deaza- and 8-bromoriboflavin with activities of 15 and 70%, respectively, of that with riboflavin; it was inactive with iso riboflavin and deoxyriboflavin.

Automated Determination of Thiamine and Riboflavin in Various Foods

Abstract Thiamine and riboflavin were determined in various foods by automated analysis. Foods hydrolyzed before diastase digestion usually yielded more of both vitamins, except for lower thiamine values in fish and nonprocessed meats. Loss of both vitamins during the separation of insoluble matter from certain fruits was prevented by adding ethylene glycol monomethyl ether. Extraction in the presence of cysteine gave higher thiamine values in samples dehydrated with heat such as milk and potatoes. Recoveries of flavin adenine dinucleotide (FAD) and thiamine pyrophosphate (TPP) were complete with the automated methods, but recoveries of FAD were less satisfactory with AOAC method 43.039—43.042. Riboflavin values by the AOAC method agreed with those by the automated method in cereals, meats, and dairy products but were slightly higher in other foods. The automated method appears more specific because it directly measures total riboflavin, including that derived quantitatively from FAD and flavin mononucleotide (FMN), while in the AOAC method the natural forms are hydrolyzed to FMN which is measured against a riboflavin standard. Much of the interfering fluorescent compounds are separated from riboflavin in the flow-through automated system. In general, variations from day to day were quite acceptable by the automated methods but often unacceptable by the AOAC riboflavin method.

Composition and Nutrient Content of Elephant (Elephas maximus) Milk

Gross composition and nutrient content were determined for milk samples from four cows of a captive family of Indian elephants during the course of eight calvings at the Portland Zoo in Oregon. The milk had a lower concentration of fat than that frequently reported for this species and showed a unique fatty acid composition with respect to the large amounts of capric acid (10:0) present. Data for amino acid analyses are given as well as values for ascorbic acid, thiamin, riboflavin, and pyridoxine. Vitamin A and carotene were shown to be almost nonexistent.

Effect of Protein and Riboflavin on Plasma Amino Acids and Hepatic Riboflavin-coenzymes in the Rat

To study the effect of protein quality and riboflavin on the concentrations of free amino acids in plasma and riboflavin-coenzymes in liver, weanling rats were fed diets containing casein, gluten or gluten plus lysine as sources of protein, supplemented with two levels of riboflavin. When compared with data obtained for animals fed 18% casein, the feeding of 18% gluten with an oral administration of 100 µg riboflavin resulted in a depression of plasma lysine, which was markedly greater than that of other essential amino acids, and in a significant increase in threonine. When the gluten diet was supplemented with 10 µg riboflavin, an interaction between riboflavin and protein resulted in a less pronounced change in the concentration of plasma lysine with no apparent change in threonine. A reduction in the essential to nonessential (EN) amino acid ratio in plasma of animals fed gluten was attributed to a decrease of most essential amino acids and to an increase in serine and glycine. Addition of lysine to the gluten diet did not significantly alter the EN ratio. Values for flavin adenine dinucleotide and total riboflavin in liver were significantly less in animals fed gluten than in animals fed casein. Comparison of data obtained for animals fed 18% casein with those of animals fed 18% gluten plus lysine showed that lysine supplementation had no significant effect on riboflavin fractions or total riboflavin of liver. The value observed for free riboflavin plus flavin mononucleotide in liver of animals fed gluten with 10 µg riboflavin was greater than that of animals fed casein or gluten plus lysine. The interaction between dietary riboflavin and protein was significant at the 5% level. The data indicated that although plasma amino acids may have value in evaluating protein status, other factors may be involved.

Metabolic Patterns in Preadolescent Children: XVI. Riboflavin Utilization in Relation to Nitrogen Intake

The riboflavin content of food, urine and feces was determined for 35 preadolescent girls fed controlled, adequate diets, the protein content of which, 18 to 88 g/day, constituted the experimental variable. Riboflavin in whole blood was determined on 24 subjects. Nitrogen intake and urinary riboflavin showed significant, positive correlation. About one-half the riboflavin intake was excreted in the urine. Correlation of intake and outgo of riboflavin was not significant. Mean fecal riboflavin values decreased sharply when nitrogen intake was reduced from 14.12 to 2.91 g/day. At the same time, the ratio of sucrose to lactose, in grams per day, increased from 104/31 to 195/3. Urinary creatinine and urinary riboflavin showed significant positive correlation as did riboflavin retention and energy balance. Riboflavin values in whole blood did not appear to be affected by differences in protein intake in 1956 when one-half the subjects were given about 2 g of protein and the other half about 3 g of protein/kg of body weight. In 1958 riboflavin blood values decreased from a mean of 21.3 to 11.4 μg/100 ml when protein intake was reduced to less than 1 g/kg of body weight but not so low as to prevent a retention of 0.3 g nitrogen/day.

Vitamin Excretion by Deer

It is well established that diet influences the intestinal flora of certain species of animals and that certain vitamins of the B complex are synthesized by microorganisms in the digestive tract (Gall, Illingworth, Cowgill and Fenton, 1948; Gall, Fenton and Cowgill, 1948). This synthetic activity is of particular importance to ruminants, and those that have been studied include cows (Johnson, et al. , 1947; Pounden and Hibbs, 1948a, b ; Hibbs, and Pounden, 1948; Teeri, et al. , 1951 a , b , 1953) and sheep (Pearson, et al. , 1953). Another ruminant for which such synthetic activity might be especially important because of its sometimes rather limited diet, and one for which nothing in this connection has been reported previously, is the deer ( Odocoileus ). Such information is presented in this report in the form of fecal and urinary excretion values for nicotinic acid, riboflavin, thiamine and vitamin B12. Three male deer ( Odocoileus virginianus ) provided by the New Hampshire Fish and Game Department were used in this study. All were between ten and twelve months of age, and weighed as follows: No. 1, 65 lbs.; No. 2, 94 lbs.; and No. 3, 82 lbs. The animals were maintained in metabolism stalls, thus making possible the regular collection of 24-hr, urine and feces samples. Daily aliquots were preserved, …

STUDIES ON NUTRITION OF POULTRY

Australian Veterinary JournalVolume 31, Issue 4 p. 91-92 STUDIES ON NUTRITION OF POULTRY (5) COMPARATIVE VALUE OF SYNTHETIC RIBOFLAVIN AND NATURAL VITAMIN B COMPLEX RICH FEEDS FOR SUPPLEMENTING WHEAT-MEATMEAL RATIONS FOR HATCHABILITY. G. L. McClymont Ph.D., B.V.Sc., G. L. McClymont Ph.D., B.V.Sc. Nutrition Research Laboratory, Veterinary Research Station, Glenfield *Faculty of Rural Science, University of New England, Armidale, N.S.W.Search for more papers by this authorD. C. Duncan, D. C. Duncan Poultry Experiment Station, Seven Hills.Search for more papers by this author G. L. McClymont Ph.D., B.V.Sc., G. L. McClymont Ph.D., B.V.Sc. Nutrition Research Laboratory, Veterinary Research Station, Glenfield *Faculty of Rural Science, University of New England, Armidale, N.S.W.Search for more papers by this authorD. C. Duncan, D. C. Duncan Poultry Experiment Station, Seven Hills.Search for more papers by this author First published: April 1955 https://doi.org/10.1111/j.1751-0813.1955.tb05524.xCitations: 2 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume31, Issue4April 1955Pages 91-92 RelatedInformation

The Vanderbilt Cooperative Study of Maternal and Infant Nutrition IV. Dietary, Laboratory and Physical Findings in 2,129 Delivered Pregnancies

The nutritional characteristics revealed by records of dietary intake laboratory assessments and physical examinations with respect to the altered physiology of pregnancy are described for an unselected group of 2129 pregnant white women attending the Vanderbilt prenatal clinic. Each patient was requested to keep dietary records for 1 week during each trimester of pregnancy. The data were examined for trends. Calorie consumption decreased between the second and third trimester in women attending the clinic. Women attending the prenatal clinic had a caloric intake 200 calories lower than women at the same point in gestation who entered the clinic at a later date. Seasonal trends were examined. The continuous schedule of acceptance of patients into the study was effective in minimizing the seasonal effect on the various groups. Long-term trends of significant magnitude were absent. The food which supplied the nutrients are indicated. 73% of the subjects were without dietary supplements. Laboratory measurements were made for the following: 1) hematologic and serum protein values 2) fat-soluble vitamins in the serum or plasma 3) serum ascorbic acid levels and 4) urinary excretion of B vitamins following load tests. Analysis of the laboratory values revealed a difference in average levels of some of the measurements depending upon when the woman first visited the clinic. This effect is seen in the values for hemoglobin packed cell volume erythrocyte count serum carotene total serum protein and serum globulin. Long-term trends were apparent in the data on the urinary excretion of thiamine riboflavin and N-methylnicotinamide and on the concentration of albumin in the serum. The gradual upward trend in the median value of riboflavin from the early part of the study to the later part of the study seem to be intrinsic within the persons studied. The expected decrease in hemoglobin concentration erythrocyte count and packed cell volume occured during pregnancy. The postpartum hemotologic values returned to levels somewhat higher than the values observed at the 5th and 9th week of gestation wheras the hemoglobin barely regianed its maximum concentration. Serum ascorbic acid showed a decrease during gestation followed by a further decline by the 5th week postpartum. In the present series the mean serum vitamin-A values decreased during pregnancy and then rose. The postpartum values for serum vitamin-A and carotene were higher than the levels observed for nonpregnant nonlactating women in an adjacent county. There was an early increase in Nmethylnicotinamide. The commonest nutritional disease found was obesity. However examiner differences were responsible for many of the differences noted on physical examination of the patients. Instances of clinically recognizable deficiency disease were absent.

The vitamin‐B content of foodstuffs fumigated with methyl bromide

AbstractThe effect of methyl bromide on some of the B‐vitamins, both in aqueous solution and in foodstuffs, has been studied. From analyses of the bromide residues, it appeared that some reaction had occurred in those solutions of nicotinic acid and nicotinamide that had been treated with high concentrations of methyl bromide. Likewise, a slight loss of nicotinamide was found on chemical analyses of the solution, and was confirmed by the appearance of an N1‐methylnicotinamide‐like substance. In milled wheat, the nicotinic acid, thiamine and riboflavin values were not diminished after treatment with various concentrations of methyl bromide, or by fumigation at different moisture contents. Similarly, no loss was found in a range of foodstuffs, including groundnuts, whole wheat, barley, peas, beans, maize and rice, when treated at concentration‐time products far higher than those normally used in practical fumigation.