Vitamin fortified rice grain using spraying and soaking methods

The objective of this work was to fortify three types of rice grains (brown, white milled and parboiled) with B complex vitamins (B₁, B₂, B₃, B₅, B₆, B₁₂), using two different physical treatment methods, (1) soaking of whole dehusked or milled rice kernels in vitamin solutions at 90 °C for 15 min and (2) full spraying of whole kernels with vitamin solution at 35 °C, both followed by oven drying. Various nutrient concentrations were added and the vitamin retention of dried fortified as well as of cooked rice were determined. Fortified rice was evaluated based on vitamin retention, estimated as the percentage of vitamin in rice after fortification treatment versus the total amount of added plus its initially vitamin quantity. It was found that the average retention of all vitamins in dried rice was high and varied from 54.3% to 85.3% for the spraying and from 53.5% to 76.2% for the soaking method respectively. After rice cooking, the retention was maintained in sufficient level (>70%) for all vitamins except for B₁₂. When excess of water was used for cooking, the water-soluble vitamins were leached; however a significant amount of vitamins still remained, varying from 13.5% (B₁₂) to 51.2% (B₁). The good retention of vitamins, even after cooking, achieved applying these relatively simple techniques, may be attributed to the absorption and diffusion of vitamins in the interior of rice kernels in high concentrations. Dried fortified rice samples properties were evaluated.     

Bestimmung der wasserl?slichen Vitamine B1, B2, B6 und B12 in Milch durch HPLC

Zusammenfassung Es werden einfache HPLC-Methoden beschrieben, die es erlauben, die wasserlöslichen Vitamine B₁, B₂, B₆ und B₁₂ in der Milch zu bestimmen. Dabei wurden gegenüber bestehenden Methoden folgende Verbesserungen erzielt: Bei der Bestimmung von Vitamin B₁ wird die nicht stöchiometrisch verlaufende Oxydation zu Thiochrom durch Zugabe von Natriumsulfit gestoppt, was zu einer deutlichen Verbesserung der Reproduzierbarkeit führt. Das Oxydationsprodukt Thiochrom wird zudem mit 1-Butanol ausgeschüttelt; dadurch werden störende Begleitstoffe abgetrennt und die Selektivität erhöht. Vitamin B₆ (Pyridoxin, Pyridoxal, Pyridoxamin und deren 5-Phosphate): Nach Spaltung der Phosphate werden die 3 Komponenten isokratisch als DDS-Ionenpaare mit HPLC und fluorimetrischer Detektion bestimmt. Vitamin B₁₂: Da geringe Konzentrationen in Milch bis jetzt nur mikrobiologisch bestimmt werden konnten, wird eine neue HPLC-Methode beschrieben, welche eine Nachweisgrenze von 0,2 g Vitamin B₁₂/L Milch aufweist.

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Determination of the water-soluble vitamins B₁, B₂, B₆ and B₁₂ in milk by HPLC

Summary Simple methods of determining the water-soluble vitamins B₁, B₂, B₆ and B₁₂ in milk by HPLC are described. Compared to existing procedures, the following improvements can be realized. The oxidation of vitamin B₁ to thiochrome is stopped by the addition of sodium sulphite. This step significantly increases repeatability. Thiochrome is then extracted with butan-1-ol, which results in fewer co-extracts and greater selectivity. After the hydrolysis of the 5-phosphates of the vitamin B₆ (pyridoxine, pyridoxal and pyridoxamine), these three vitamers are determined by isocratic HPLC as DDS-ionpairs and with fluorimetric detection. As only microbiological methods have so far been used for the determination of minute quantities of vitamin B₁₂ in milk, a new HPLC procedure is proposed with a detection limit of 0.2 g vitamin B₁₂/L milk.

     

Analysis of Water-Soluble Vitamins in Honey by Isocratic RP-HPLC

An isocratic RP-HPLC method has been developed for the identification and quantification of water-soluble vitamins in honey. The mobile phase tested was an aqueous solution of sulphuric acid and the detection was carried out simultaneously by UV and fluorescence. The separation of vitamins C (l-ascorbic acid), B₁ (thiamine), B₃N (nicotinamide), B₃H (nicotinic acid), B₅ (d-pantothenic acid) and B₆ (pyridoxine) is achieved in these conditions in 15 min. The addition to the mobile phase of methanol 2 %?v/v reduced significantly the analysis time in the separation of these vitamins up to 10 min. Moreover, in presence of a cationic surfactant hexadecyltrimethylammonium bromide (CTAB) in the mobile phase, the separation of vitamin C, B₁, B₃N, B₃H, B₂ (riboflavin) and B₆ is possible in 6 min. The combination of both mobile phases, H₂SO₄/methanol and H₂SO₄/methanol/CTAB, has been applied to the analysis, in isocratic mode, of several monofloral honeys (rosemary, thyme, lavender, chestnut, echium) and a honeydew honey in a short time analysis.     

New voltammetric procedure for determination of thiamine in commercially available juices and pharmaceutical formulation using a lead film electrode

A simple, reliable and reproducible method, based on adsorptive stripping voltammetry (AdSV), for determination of vitamin B₁ (thiamine) in pharmaceutical preparation and food is described in this paper. The in situ plated lead film electrode was used as a working electrode. The lead film was formed and thiamine was accumulated at −1.25 V (vs. Ag/AgCl) on a glassy carbon electrode. Then, the preconcentrated thiamine was reduced by scanning the potential of the electrode from −1.25 to −1.55 V using a square-wave technique. The linear range was from 0.0133 to 0.265 mg L⁻¹ for vitamin B₁, with the regression coefficient of 0.999. The detection limit for vitamin B₁ was 0.0053 mg L⁻¹ for the accumulation time 120 s. The method developed was applied to the determination of thiamine in certified reference material (BCR-485), pharmaceutical formulation and commercially available juices, and the assay results were satisfactory.     

Net flux of nutrients across splanchnic tissues of lactating dairy cows as influenced by dietary supplements of biotin and vitamin B12

Biotin and vitamin B₁₂ are coenzymes in reactions that are essential to propionate metabolism in dairy cows. The objective of the present studies was to determine whether an increased dietary supply of these vitamins would change the net flux of nutrients through the rumen, the portal-drained viscera (PDV), the total splanchnic tissues (TSP), and the liver. Four lactating cows equipped with ultrasonic flow probes around the right ruminal artery and the portal vein and catheters in the right ruminal vein, the portal vein, one hepatic vein, and one mesenteric artery were fed 12 times per day a mixed ration at 95% of ad libitum dry matter intake. Daily supplements of 500 mg of vitamin B₁₂ + 20 mg of biotin or no vitamin supplement (study 1) or 500 mg of vitamin B₁₂ alone or with 20 mg of biotin (study 2) were fed according to a crossover design with two 4-wk periods in each study. On the last day of each period, blood flow was recorded and blood samples were collected every 30 min for 4 h. In study 1, biotin and vitamin B₁₂ given together increased milk production and milk protein yields compared with the control diet. The supplement increased appearance of the 2 vitamins across the PDV and TSP. It also reduced the net portal appearance of ammonia and total volatile fatty acids across the PDV. In study 2, compared with the 2 vitamins together, vitamin B₁₂ alone increased glucose flux across PDV and TSP as well as its arterial concentration and PDV flux of ammonia. With the diet used in the present experiment, the major effects of the vitamin supplements seem to be mediated through changes in ruminal fermentation and gastrointestinal tract metabolism rather than by effects on hepatic metabolism.     

Enzymatic assay of dehydrogenase substrate based on the detection of superoxide anion

The oxidation of NADH using NADH oxidase from Bacillus licheniformis or diaphorase from Clostridium kluyveri, was found to produce superoxide anion (O₂⁻). The generated O₂⁻ reduced water-soluble tetrazolium salt WST-1 to WST-1 formazan. The formation of WST-1 formazan was monitored as a change in the absorbance at 438 nm. The formation of WST-1 formazan was found to be proportional to the NADH concentration. As a result, a linear curve was obtained within the range of 0.5 μM–50 μM NADH concentration. The concentration of NADH was determined by chemiluminescence using lucigenin specific for O₂⁻ instead of WST-1. Application of NADH oxidase from Bacillus licheniformis was found to be 400 times stronger chemiluminescence than that of diaphorase with a lower detection limit of 15 nM. The present method was applied to determine ethanol combined with yeast alcohol dehydrogenase. The ethanol concentrations of various kinds of alcoholic beverages obtained by the present method were compared with those obtained using F-kit method. A good linear correlation was observed between them (r=0.9997) and the slope (1.005) was very close to unity, suggesting that the present method could be applied for the determination of ethanol in practical samples.     

Methods quantitative for determination of water-soluble vitamins in premixes and fortified food products by micellar electrokinetic chromatography on short end of the capillary

It was purposed new technique by micellar electrokinetic chromatography on short end of the capillary (capillary electrophoresis system Agilent 3D CE, DAD, quartz capillary HPCE stndrd cap 56 cm, 50 microm, 50 mM borate buffer pH=9,3, 100 mM sodium dodecil sulfate) for simultaneous determination of water-soluble vitamins (B1, B2, B6, B12, PP, B5, B9, C, B8) in fortified food products and premixes. It was observed on 6 samples of vitamin premixes and 28 samples of fortified food products using this technique. Our findings are consistent with the results of research on certain vitamins, conducted by other methods. The developed technique can be used in analysis of water-soluble vitamins in premixes and fortified food products.     

Effects of dietary supplements of folic acid and vitamin B12 on metabolism of dairy cows in early lactation

The present experiment was undertaken to determine the effects of dietary supplements of folic acid and vitamin B₁₂ given from 3 wk before to 8 wk after calving on lactational performance and metabolism of 24 multiparous Holstein cows assigned to 6 blocks of 4 cows each according to their previous milk production. Supplementary folic acid at 0 or 2.6 g/d and vitamin B₁₂ at 0 or 0.5 g/d were used in a 2 × 2 factorial arrangement. Supplementary folic acid increased milk production from 38.0 ± 0.9 to 41.4 ± 1.0 kg/d and milk crude protein yield from 1.17 ± 0.02 to 1.25 ± 0.03 kg/d. It also increased plasma Gly, Ser, Thr, and total sulfur AA, decreased Asp, and tended to increase plasma Met. Supplementary B₁₂ decreased milk urea N, plasma Ile, and Leu and tended to decrease Val but increased homocysteine, Cys, and total sulfur AA. Liver concentration of phospholipids was higher in cows fed supplementary B₁₂. Plasma and liver concentrations of folates and B₁₂ were increased by their respective supplements, but the increase in plasma folates and plasma and liver B₁₂ was smaller for cows fed the 2 vitamins together. In cows fed folic acid supplements, supplementary B₁₂ increased plasma glucose and alanine, tended to decrease plasma biotin, and decreased K_m of the methylmalonyl-coenzyme A mutase in hepatic tissues following addition of deoxyadenosylcobalamin, whereas it had no effect when cows were not fed folic acid supplements. There was no treatment effect on plasma nonesterified fatty acids as well as specific activity and gene expression of Met synthase and methylmalonyl-coenzyme A mutase in the liver. Ingestion of folic acid supplements by cows fed no supplementary B₁₂ increased total lipid and triacylglycerols in liver, whereas these supplements had no effect in cows supplemented with B₁₂. The increases in milk and milk protein yields due to folic acid supplements did not seem to be dependent on the vitamin B₁₂ supply. However, when vitamin B₁₂ was given in combination with folic acid, utilization of the 2 vitamins seems to be increased, probably more so in extrahepatic tissues. Metabolic efficiency seems also to be improved as suggested by similar lactational performance and dry matter intake for cows fed supplementary folic acid but increased plasma glucose and decreased hepatic lipids in cows fed folic acid and vitamin B₁₂ together.     

Micellar Electrokinetic Chromatography Method for Determination of the Ten Water-Soluble Vitamins in Food Supplements

The separation and determination of the ten water-soluble vitamins by using capillary electrophoresis in the micellar electrokinetic chromatography in a single run are proposed. The method uses low toxicity and cost solvent (ethanol) as modifier of background electrolyte (BGE) attending to the Green Chemistry principles. The electrophoretic method uses 10.0 % (v/v) ethanol, 2.0 % (w/v) SDS, 0.02 mol?L^?1 borate at pH 8.70 as BGE. The standard and real sample solutions were injected in the eletrophoretic system by hydrodynamic injection under pressure of 0.80 psi for 8 s, and the separation was carried out in a fused silica capillary under a potential of 28 kV at 25 °C; the analytical signals were monitored at 214 nm. The analytical method is precise (r.s.d.?<?6 %), accurate (better than 9 %), selective, sensitive, robust, simple, and presents high analytical frequency as ten water-soluble vitamins were separated in only 18 min, with migration times of 5.75?±?0.02, 6.81?±?0.02, 8.13?±?0.04, 8.80?±?0.07, 8.98?±?0.06, 11.10?±?0.08, 11.34?±?0.05, 13.85?±?0.15, 14.82?±?0.04, and 17.85?±?0.30 min. Detection and quantification limits of 0.34, 0.32, 0.27, 0.20, 2.50, 4.98, 4.92, 0.30, 0.86 and 0.28 mg?L^?1 and 1.02, 0.97, 0.83, 0.62, 7.56, 15.09, 14.91, 0.90, 2.59 and 0.83 mg?L^?1, for vitamins PP (nicotinamide), B₁₂ (cyanocobalamin), B₂ (riboflavin), B₆ (pyridoxine), B₈ (biotin), C (ascorbic acid), B₅ (pantothenic acid), B₃ (nicotinic acid), B₁ (thiamine), and B₉ (folic acid), respectively. Excellent recoveries (intra and inter-day) were obtained and, when the method was applied to food supplement analyses the results were in agreement with the conventional HPLC methods.     

Vitamins B1 and B2 contents in cultivated mushrooms

Mushrooms have long been treated as a delicacy. Nowadays however, many researchers consider them to be nutraceutical foods, which has stimulated new and existing Brazilian producers to search for more productive techniques and to introduce other species. The objective of this study was to determine the vitamin B₁ and B₂ contents in mushrooms. The main species of mushroom cultivated in Brazil and analysed in this study are: Agaricus bisporus (white button mushroom and portobello), Lentinula edodes (shiitake) and Pleorotus spp. (shimeji and oyster mushroom). The methodology employed used acid hydrolysis followed by enzymatic hydrolysis and separation of the vitamins by high performance liquid chromatography using a C₁₈ reverse phase column and fluorescence detector. The results obtained for thiamine (vitamin B₁) were from 0.004 to 0.08 mg/100 g and for riboflavin (vitamin B₂), from 0.04 to 0.3 mg/100 g.     

Variations of vitamin and mineral contents in raw goat milk of the indigenous Greek breed during lactation

Raw goat milk samples from the indigenous Greek breed in the area of Ioannina, northwestern Greece, were collected during one lactation and analyzed for vitamins A, E, B₁, B₂, and C and for minerals Ca, Mg, P, Na, K, Cu, Fe and Zn. Also, the major constituents of goat milk, namely fat, protein, lactose and solids-non-fat, were determined. The average composition (%) of milk was: fat 4.10, protein 3.36, lactose 4.48 and solids-non-fat 8.54. The mean concentration of the fat-soluble vitamins retinol (A) and α-tocopherol (E) were 0.013 and 0.121 mg/100 ml, respectively. The mean concentration of the water-soluble vitamins, thiamin (B₁), riboflavin (B₂) and ascorbic acid (C) were 0.260, 0.112 and 5.48 mg/100 ml, respectively. Seasonal variations were observed for all vitamins studied. Thiamin had significantly (P < 0.05) higher concentrations during summer than in winter and early spring. The observed variations of the studied vitamins might be attributed to the differences in the feeding of goats during lactation. The mean mineral contents (mg/100 g) of goat milk were Ca 132, P 97.7, Na 59.4, K 152, Mg 15.87, Cu 0.08, Fe 0.06, Zn 0.37 and Mn 6.53 μg/100 g. Seasonal variations were observed for the major minerals Ca, P, K, and the trace elements Cu and Zn.     

Determination of water-soluble vitamins in soft drinks and vitamin supplements using capillary electrophoresis

A method for the determination of six water-soluble vitamins based on capillary electrophoresis (CE) operated in micellar mode was developed. Thiamine hydrochloride (vitamin B1), riboflavin (vitamin B2), pyridoxine hydrochloride (vitamin B6), pantothenic acid (vitamin B5), nicotinamide (vitamin B3), and cobalamin (Vitamin B12) could be separated in a single run. All CE parameters such as buffer composition and operation temperature were optimized in order to achieve better separation. Relative standard deviations (RSDs) of the described method ranged from 1.08 to 3.68% (intra-day precision) and 1.26 to 3.35% (inter-day precision). The method was then used for measuring various soft drinks and vitamin supplements directly without any step of sample cleanup. The determination of niacin was successful for all samples tested, reaching recoveries near 100%. Riboflavin and pyridoxine were quantified successfully in some but not all samples. Therefore, an evaluation on a case-by-case basis is mandatory. When applicable, this method provides a fast, accurate, simple, and inexpensive way to quantify selected vitamins, and is therefore well suited for routine analysis in soft drink industry.     

The nutrient composition of three cuts obtained from P-class South African pork carcasses

The shoulder, loin and leg from P-class pork carcasses were used to determine the nutrient composition of both raw and cooked cuts. Significantly lower fat content were observed in the current study for the leg (5.21 g/100 g) and loin (6.99 g/100 g) compared to the shoulder cut (10.32 g/100 g). The overall percentage fat for all three cuts was less than 10% which is recommended by the South African Heart Mark. The cooked loin cut contained the most protein (27.50 g/100 g) of the three cooked cuts. When compared to other meat products (beef, mutton and chicken) it is clear that pork is a good source of B vitamins, especially vitamin B₃. The cooked loin cut contained the least vitamin B₁ (0.22 mg/100 g), B₂ (0.02 mg/100 g) but the most vitamin B₃ (7.09 mg/100 g), of the three cooked cuts. The 100 g cooked shoulder, loin and leg cuts provide on average 40.11% protein, 5.19% magnesium, 3.37% calcium, 24.29% phosphorus, 18.22% zinc, 22.33% iron and 22.50% vitamin B₁, 2.57% vitamin B₂ and 42.6% vitamin B₃ of Recommended Daily Allowances for males, age 25–50. Energy from a 100 g portion provides 5.81% of the Recommended Daily Allowances. To conclude, the pork cuts are undoubtedly a good source of nutrients that is required for good health because it is high in protein, have a low fat content and are a nutrient-packed choice for the family and compares favourably with the fat, energy, and cholesterol content of many other meats and poultry.     

The effects of pre-treatment with vitamin B6 on memory retrieval in rats

The effects of pre-treatment with vitamin B₆ on memory retrieval in adult male Wistar rats were evaluated using a step-through passive avoidance task. The rats were divided into three groups of 10 each. All animals were fed standard rodent chow. Vitamin B₆ (50 or 100 mg/kg) was administered intraperitoneally (i.p.) every other day for 1 month before training was initiated. Three retention tests were performed to assess the memory of the rats. Vitamin B₆ (100 mg/kg) significantly increased the step-through latency of the passive avoidance response compared with the control in the first retention test of the passive avoidance paradigm (p < 0.05). In addition, vitamin B₆ at 100 mg/kg significantly increased memory retrieval in the second and third retention tests conducted 2 days and 1 week after training, respectively, compared with the control (p < 0.05). These results indicate that pre-treatment with vitamin B₆ potentially enhances memory retrieval.     

B Vitamins in Selected Variety Breads Commercially Produced in Major U.S. Cities

Three enrichment vitamins (thiamin, riboflavin, niacin) and three other (folic acid, pantothenic acid, vitamin B₆) B vitamins were determined in 10 types, up to four brands of each type, of variety breads (including tortillas) purchased from four major U.S. cities. In general, bread types traditionally enriched and not containing nonflour components as significant ingredients met the vitamin enrichment standards. In many products, the contents of all six vitamins varied appreciably from brand to brand. In contrast to wholewheat bread and some enriched breads, corn tortillas were consistently low in ail vitamins except vitamin B₆.     

Simplified fluorimetric methods for determination of vitamin B6 in food materials

Summary A simple fluorimetric method for the determination of vitamin B₆ in food materials is proposed, enabling total vitamin B₆ to be determined after the chromatographic removal of interfering substances on Dowex 50 WX 8 columns. Pyridoxol, pyridoxal and pyridoxamine are transferred into the highly fluorescent lactone of 4-pyridoxic acid. The method is specific and agrees well with the microbilogical assay. Three or four determinations can be performed in eight hours.

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Vereinfachte fluorimetrische Methoden zur Vitamin-B₆-Bestimmung in Lebensmitteln

Zusammenfassung Eine einfache fluorometrische Methode zur Vitamin-B₆-Bestimmung wurde vorgeschlagen, die den gesamten Vitamin-B₆-Gehalt nach chromatographischer Beseitigung der interferierenden Substanzen auf Dowex-50-WX8-Säulen ermittelt. Pyridoxol, Pyridoxal und Pyridoxamin werden in das stark fluorescierende Lacton der 4-Pyridoxinsäure überführt. Die Methode ist spezifisch und stimmt gut mit dem mikrobiologischen Test überein. Drei bis vier Bestimmungen können in 8 Std durchgeführt werden.

     

培养基质量控制对维生素B12含量测定的影响

目的 GB 5413.14-2010微生物法检测维生素B₁₂中培养基的质量和配方直接影响莱士曼氏乳杆菌在整个检测过程中的活化,接种和测定。方法 为解决这一问题,本文通过比较不同配方菌株活化培养基和种子液制备肉汤培养基及不同品牌测定培养基对维生素B₁₂ 结果测定的影响。利用莱士曼氏乳杆菌对维生素B₁₂的特异性和灵敏性,定量测定质控样品中维生素B₁₂的含量,并通过质量控制措施对测定结果进行分析评价。结果 方案设计中A2种活化菌株方式所用培养基和B1品牌的维生素B₁₂测定培养基得到的拟合曲线线性更好,质控结果组间差异也更小。结论 表明培养基质量控制对维生素B₁₂检测的准确度和稳定性极为重要。     

Influence of methionine supply on the response of lactational performance of dairy cows to supplementary folic acid and vitamin B12

The present experiment was undertaken to determine if the effects of supplementary folic acid on lactational performance were caused by improved methylneogenesis and if the supply in vitamin B₁₂ could affect this metabolic pathway. In this eventuality, supplementary Met, a major source of preformed methyl groups, should reduce the requirements for these vitamins. Sixty multiparous Holstein cows were assigned to 10 blocks of 6 cows each according to their previous milk production. Within each block, 3 cows were fed a diet estimated to supply Met as 1.83% metabolizable protein and 3 cows were fed the same diet supplemented with 18 g of rumen-protected methionine (RPM) to supply Met as 2.23% of metabolizable protein. Within each level of Met, cows received no vitamin supplement or weekly intramuscular injections of 160 mg of folic acid alone or combined with 10 mg of vitamin B₁₂ from 3 wk before to 16 wk after calving. There was no treatment effect on dry matter intake during pre- and postcalving periods: 13.4 ± 0.4 and 21.8 ± 0.4 kg/d, respectively. Milk production was not affected by RPM supplementation. Folic acid and vitamin B₁₂ given together tended to increase milk production during the 16 wk of lactation. This effect was more pronounced during the first 4 wk of lactation: 37.5, 37.7, and 40.3 ± 0.9 kg/d for cows receiving no vitamin supplement, folic acid alone, or folic acid combined with vitamin B₁₂, respectively. Milk fat yield was not affected by treatments. Lactose, crude protein, and total solid yields were greater, in early lactation, in cows injected with folic acid and vitamin B₁₂ together but this effect diminished as lactation progressed. Intramuscular injections of folic acid alone or combined with vitamin B₁₂ tended to decrease plasma concentrations of homocysteine from 5.51 μM with no vitamin supplement to 4.54 and 4.77 ± 0.37 μM, respectively. Results of the present experiment suggest that the effects of the combined supplement of folic acid and vitamin B₁₂ on lactational performance of dairy cows were not due to an improvement in methyl groups supply, because RPM supplement, a source of preformed methyl groups, did not alter the cow responsiveness to vitamin supplements.     

Short communication: Effect of fatty acid supplements on apparent ruminal synthesis of B vitamins in lactating dairy cows

The effect of fat supplements (FS) providing different proportions of saturated (SFA) and unsaturated (UFA) fatty acids on supply, apparent ruminal synthesis (ARS), and duodenal flow (DF) of some B vitamins (thiamine, riboflavin, niacin, vitamin B₆, folates, and vitamin B₁₂) were evaluated in an experiment using 8 ruminally and duodenally cannulated lactating Holstein cows. The experiment was a replicated 4 × 4 Latin square design with 21-d treatment periods. The 4 treatments were a control diet without fatty acid supplement and 3 diets with 2.5% additional fatty acids from supplements containing (1) SFA, (2) an intermediate mixture of SFA and UFA, or (3) UFA. All diets were served as a total mixed ration once daily at 115% of the expected intake. B-vitamin concentrations were analyzed in feed and duodenal digesta. Apparent ruminal synthesis of each B vitamin was calculated as the DF minus the intake. B-vitamin concentrations were similar among the 4 treatments; consequently, daily intake of the vitamins followed the same pattern as dry matter intake. Adding FS decreased B-vitamin intakes (except vitamin B₁₂), as did increasing the proportion of UFA. Riboflavin and niacin DF and ARS, expressed as total daily amount or per unit of dry matter intake, were not affected by FS, but increasing the proportion of UFA decreased riboflavin and niacin DF and ARS. Fat supplements decreased DF of vitamin B₆, expressed either as total daily amount or per unit of dry matter intake. No treatment effects were observed on total daily folate DF and ARS. However, when expressed per unit of dry matter intake, folate DF and ARS were greater when cows were fed FS and they increased linearly with the proportion of UFA in the supplement. Inclusion of fat supplements into the dairy cow diet had a limited effect on the fate of most B vitamins in the rumen although increasing the proportion of UFA in the FS linearly decreased apparent synthesis of riboflavin and niacin in the rumen and the amounts of these vitamins reaching the small intestine.     

Multivitamin Analysis of Fruits, Fruit–Vegetable Juices, and Diet Supplements

Vitamins are organic compounds that are required for various biological functions. In general, vitamins are not synthesized in the human body, but lack or deficiency of them may lead to certain diseases. Determinations of 11 vitamins in various products were performed, which included ascorbic acid (C), seven vitamins of the B group (thiamine B₁, riboflavin B₂, nicotinamide B₃, pantothenic acid B₅, pyridoxine B₆, folic acid B₉, and cyanocobalamin B₁₂), as well as three fat-soluble vitamins (retinol A, cholecalciferol D₃, and α-tocopherol E). A column with RP18 stationary phase and a diode array detector with properly selected analytical wavelengths for each compound were used. A gradient of trifluoroacetic acid in water with methanol was used as the mobile phase. Limits of quantification in the range of 0.70–2.90 μg/mL for water-soluble vitamins and 1.85–15.84 μg/mL for fat-soluble vitamins were obtained. Those values are sufficient for determinations of the aforementioned compounds in foodstuff. The developed procedure of sample preparation together with chromatographic system can be used for food quality monitoring in the food industry.