Vitamin B12 and folate in non-institutionalized urban older people

Vitamin B12 and folate deficiencies are the main nutritional determinants of hyperhomocysteinemia, which is an independent risk factor for cardiovascular diseases. There is scarce information about nutritional status on vitamin B12 and serum levels of folate in Mexican older people. The objective was to evaluate the nutritional status of vitamin B12 and folic acid concentration in non-institutionalized, urban elderly men and women subjects. One hundred volunteers over 60 years were included in this cross-sectional study. Serum levels of vitamin B12 and folate were measured. In addition some biochemical and anthropometric indicators were also evaluated. Considering serum values of vitamin, 30% had vitamin B12 deficiency, 52% normal status and 18% with high levels. None subjects had folic acid deficiency, by the contrary, a high proportion (62%) showed elevated levels in serum. There was an effect of sex on vitamin B12 status. Elderly men showed significantly lower levels of vitamin B12, and it was according with significant higher prevalence of vitamin B12 deficiency in this group as compared with the women group. The high proportion of vitamin B12 deficiency found in this study underline a possible public health problem and guarantee further survey-studies about vitamin B12 status and to explore causes and consequences of the deficiency. Finally, due the sample size and the design of the study, the results must be seen with caution and not try to generalize.     

Synthesis and characterization of polymer supported vitamin B12 model compounds

A series of polymer supported cobalt complexes have been synthesized by the reaction of Co(II)‐SALEN (salicylaldehyde ethylenediimine) and other variations thereof with the chelating resin containing vinyl pyridine. The polymer supported complexes have been characterized by electronic and infrared spectra. The presence of polymer supports has a marked influence on the UV–visible bands observed in the electronic spectra of cobalt complexes. These polymer supported complexes are also investigated by cyclic voltammetry. The electronic spectral data and cyclic voltammetric data for free complexes and polymer supported complexes are compared. The discernible differences in the spectral and electrochemical data suggest the presence of pentacoordinate cobalt in the polymer matrix. © 2000 Society of Chemical Industry     

Lowering plasma homocysteine with vitamins B6, B12, and folic acid. Effect on lipids concentration in patients with secondary hyperlipoproteinemia type IV, with and without Lovastatina treatment

The concentration of plasma homocysteine was diminished by the oral use of vitamins B6 (300 mg/day), B12 (250 microg/day) and folic acid (10 mg/day), and the effect was studied in the lipids of patient with hiperlipoproteinemia secondary type IV, during 120 days, in 30 patients, 45 to 70 years old, with myocardial heart attack. They were divided in group A (n=15) without treatment with Lovastatin and group B (n=15) with Lovastatin. Basal homocysteine concentration was 17.4 +/- 1.0 micromol/L and 16.7 +/- 1.0 micromol/L for the groups A and B respectively, diminishing 24% at the end of the experimental time, in both groups. Total cholesterol decreased below 220 mg/dl, while the triglycerides diminished 25.4 mg/dl and 27.0 mg/dl in groups A and B respectively, by each micromol/L of homocysteine catabolissed. Low density lipoproteins (LDL) and very low density (VLDL) diminished significantly (p < 0.005), while the high-density (HDL) increased 1.0 mg/dl in group A and 1.15 mg/dl in group B, for each micromol/L of homocysteine metabolized, lowering the coronary risk factor in 28.5% group A and 35.9% group B. We concluded that these vitamins decreased plasma homocysteine concentration, promoting the lowering of lipids and lipoprotein concentratation in this type of patients; while Lovastatin doesn't reduce homocysteine, but it had a synergic effect with the vitamins, dicreasing the lipid concentration, in group B.     

Adsorption of vitamin B12 on ordered mesoporous carbons coated with PMMA

Ordered mesoporous carbons CMK-3 and CMK-1 were prepared from SBA-15 and MCM-48 materials with pore diameters 3.9 nm and 2.7 nm, respectively. When both mesoporous carbons were coated with about 10 wt.% poly(methyl methacrylate) (PMMA), the pore diameters decreased from 3.9 nm to 3.4 nm for CMK-3 and from 2.7 nm to 2.5 nm for CMK-1. These mesoporous carbons containing about 10 wt.% PMMA were studied as adsorbents of Vitamin B 12 (VB12) from water solutions, and their performances were compared with that of pristine CMK-3, CMK-1. Compared with CMK-1, CMK-3 showed higher vitamin B12 adsorption due to a larger mesopore volume, a higher BET surface and a larger pore diameter. After coated with PMMA, both mesoporous carbons showed higher adsorption capacity than pristine materials. The adsorption properties were influenced by the pore structure and surface properties of mesoporous carbons.     

Multifunctional mussel-inspired Gelatin and Tannic acid-based hydrogel with pH-controllable release of vitamin B12

Hydrogels have emerged to be an impeccable material for a large variety of applications over the past few decades. In the field of biomedical applications, remarkable progress has been observed in the effort of fabricating numerous hydrogel systems. In this work, gelatin and tannic acid-based stretchable and adhesive hydrogel has been synthesized to study the release behavior of vitamin B₁₂. Successful formation of the synthesized hydrogels was confirmed by Fourier transform infrared and X-ray diffraction analysis. The morphology of the surfaces and the cross section of such hydrogels were studied with Scanning electron microscopy analysis. Swelling behavior of our hydrogel was studied with Design Expert software. The maximum swelling of the hydrogel was found to be around 137 g/g. Adhesive property was demonstrated on various surfaces to observe the adhesiveness of the fabricated hydrogel. Blood compatibility study was also performed. The release behavior of vitamin B₁₂ was performed in two different pH media and it was found to have enhanced value in the fluid mimicking the intestine. This work provides a new prospect for designing hydrogels with stretchable and adhesive properties with pH-controllable drug delivery applications along with other promising applications in various fields of research.     

Studies of the uptake of vitamin B12 by styrene-based porous polymeric adsorbents

Porous polymeric adsorbents based on styrene were studied for the uptake of vitamin B₁₂ from aqueous solutions under static conditions. The effect of various parameters on the uptake was studied. The uptake of vitamin B₁₂ by polymeric adsorbents and their subsequent elution from the polymer matrix was also studied under dynamic conditions to assess their utility for the isolation of this compound. Results obtained point to their potential use for the recovery of vitamin B₁₂.     

HPLC法测定复方利血平片中氢氯噻嗪、硫酸双肼屈嗪、维生素B_1和维生素B_6的含量

采用HPLC法测定复方利血平片中氢氯噻嗪、硫酸双肼屈嗪、维生素B1和维生素B6的含量。Kromasil C-18色谱柱（250 mm×4.6 mm,5μm）,检测波长210 nm,以0.2%己烷磺酸钠（用冰醋酸调节pH=3.5）-甲醇-乙腈（75∶20∶5）为流动相,流速1.0 mL/min,进样量20μL,柱温30℃。结果表明,氢氯噻嗪的线性范围为49.6～496.0μg/mL（R2=0.999 4）,精密度RSD为0.12%（n=6）,重复性RSD为0.45%（n=6）,平均回收率为99.74%（RSD=0.78%,n=9）;硫酸双肼屈嗪的线性范围为16.8～336.0μg/mL（R2=0.999 3）,精密度RSD为0.06%（n=6）,重复性RSD为0.21%（n=6）,平均回收率为99.83%（RSD=0.08%,n=9）;维生素B1的线性范围为4.0～80.0μg/mL（R2=0.998 7）,精密度RSD为0.56%（n=6）,重复性RSD为0.96%（n=6）,平均回收率为99.02%（RSD=1.13%,n=9）;维生素B6的线性范围为4.0～80.0μg/mL（R2=0.999 1）,精密度RSD为0.23%（n=6）,重复性RSD为0.78%（n=6）,平均回收率为99.56%（RSD=0.48%,n=9）。此法分离度好,峰形对称,分析周期短,重复性好,简单易行,可同时测定复方利血平片中氢氯噻嗪、硫酸双肼屈嗪、维生素B1和维生素B6的含量。     

Interactions among indicators of B1, B2, B6 and vitamin C status in university students

In 209 young university students (109 males and 80 females) with body mass index within the normal range, the activation coefficient of the erythrocyte transketolase (ETKAC) glutathione reductase (EGRAC) and aspartate amino transferase (EASTAC) as well as the circulating levels of vitamin C were determined. Using the usual cutoff points for ETKAC and serum vitamin C and higher than usual cutoff points for EASTAC and EGRAC 99, 95, 92, and 87% of the study subjects exhibited activation coefficients which were compatible with an acceptable status for vitamin B2, B6, C and B1 respectively. A correlation analysis showed a high correlation (r = 0.81) between erythrocyte indicators of B1 and B2 status a lower correlation between indicators of the status of these vitamins and B6 and no correlation between the indicators of B1, B2, and B6 status and serum vitamin C. This study indicated that in this largely nutritionally adequate population, the activation coefficient of the erythrocyte enzymes used here as markers of the nutritional status of B1, B2, and B6 were related between themselves and varied in the same direction. These changes, however, were not associated with circulating levels of vitamin C.     

羧化多壁碳纳米管/维生素B_(12)修饰电极测定多巴胺

制备了羧化多壁碳纳米管/维生素B12修饰玻碳电极,利用循环伏安法研究了多巴胺(DA)在此修饰电极上的电化学行为。结果表明,在pH为6.48的PBS缓冲溶液中,此修饰电极对DA有很强的电催化作用,明显增强了峰电流,峰电位差ΔEp由196 mV减小至69 mV,提高了电极反应的可逆性。在优化实验条件下,此修饰电极所测DA氧化峰电流与DA浓度在1.0×10-5~5.0×10-5mol/L及1.0×10-3~1.0×10-2mol/L范围内均呈线性,线性方程分别为y=373.78x+71.726(R2=0.995 8)和y=57.2x+365.22(R2=0.986 6),其中低浓度区的相关系数较高,应用于实际样品测定时结果较为满意。检测限可达8.0×10-8mol/L。     

HPLC法同时测定五维B颗粒中的烟酰胺、维生素B1、维生素B2的含量

目的建立同时测定五维B颗粒中维生素B1、维生素B2、烟酰胺三组分含量的高效液相色谱法.方法采用ODS C18柱、柱长150×4.6mm流动相为甲醇乙腈0.06%己烷磺酸钠和0.04%庚烷磺酸钠的混合液冰醋酸=4530241流速1.2mL/min柱温30℃波长275nm,外标法计算.结果线性范围分别是烟酰胺90～210μg/mL;r=0.999维生素B2 12～32μg/mL;r=0.999、维生素B1 25～65μg/mL;r=0.998,回收率分别为烟酰胺99.5%、维生素B2 99.7%、维生素B1 100.3%.结论本方法分离效果好、辅料无干扰、快速、简便、准确适合于该制剂3组分的同时测定.     

Studies of the uptake of vitamin B12 and theophylline by phenol-based porous condensate cation exchangers

Porous condensate cation exchangers based on phenol were evaluated for the uptake of vitamin B₁₂ and theophylline from aqueous solutions under static conditions. The effect of various parameters on the uptake was studied. The uptake of these compounds by porous cation exchangers and their elution performance from polymer matrices were studied under dynamic conditions to assess their utility for the isolation of medicinally important compounds. The results obtained indicate that they may prove useful in this respect.     

Cholesterol metabolism and vitamin B6: II. Intestinal cholesterogenesis in vitamin B6 deficient rats

The in vitro incorporation of 1-¹⁴C-acetate into cholesterol by vitamin B₆ deficient and pair-fed rat intestinal tissue was assayed. It was found that vitamin B₆ deficiency increases, by a twofold factor, the incorporation of 1-¹⁴C-acetate into the cholesterol biosynthetic chain, when using a segment of the ileum, and on the other hand no increase was observed when using a segment from the jejunum. The production of¹⁴CO₂ from 1-¹⁴C-acetate was not found altered by a vitamin B₆ deficiency when using segments from the jejunum or the ileum. The effect of sodium cholate and sodium chenodeoxycholate on the incorporation of radioactivity into cholesterol and on the production of radioactive CO₂, with 1-¹⁴C-acetate as a substrate, was assayed with the two groups of animals. The significance of these findings and the posible relationships between these factors are discussed.     

Liposoluble vitamin B1 microcapsules: Preparation,characterization, stabilization,and bioaccessibility

Thiamine (VB₁) is an essential water-soluble vitamin that is necessary in our daily diet. However, its instability when exposed to external factors poses a limitation on its application in the food industry. To address this issue and increase its application in fat-rich food systems, this study developed liposoluble VB₁ microcapsules via freeze-drying, utilizing β-cyclodextrin as a wall material and polyglycerol fatty acid ester as an emulsifying agent. The VB₁ microcapsules were characterized in terms of their particle size distribution, morphology, solubility, and stability in soybean oil, as well as their in vitro bioaccessibility. The results showed that the average particle size of VB₁ microcapsules was 83.73 μm with a nonuniform, somewhat wrinkled spherical structure. The solubility of the VB₁ microcapsules in soybean oil was increased to 142.86 mg kg^–1. The retention rates of VB₁ in soybean oil was found to be above 95% after 48 h of UV irradiation and 96.44% after heating for 7 days at 60°C. The presence of VB₁ microcapsules did not significant impact on the oxidation stability of soybean oil. The bioaccessibility of VB₁ in soybean oil was 82.81%. This work provides a useful and novel direction for the application of VB₁ in high-fat diets. Practical applications: VB₁ is one of the B-group vitamins that assists in maintaining normal glucose metabolism. However, it is readily inactivated when exposed to UV radiation, certain pH conditions, and other factors. In this work, the VB₁ microcapsules prepared by freeze-drying exhibited high liposolubility, stability, and bioaccessibility, rendering them suitable for applications in oil-based systems. This work not only provides a new delivery system to facilitate VB₁ supplementation in humans, but also helps to elucidate its application prospect of VB₁ in fat-rich foods, such as edible oil, butter, margarine, rich-fat dressings, and so on, thus improves the application value of VB₁.     

B12Hn and B12Fn: planar vs icosahedral structures

Using density functional theory and quantum Monte Carlo calculations, we show that B₁₂H_n and B₁₂F_n (n = 0 to 4) quasi-planar structures are energetically more favorable than the corresponding icosahedral clusters. Moreover, we show that the fully planar B₁₂F₆ cluster is more stable than the three-dimensional counterpart. These results open up the possibility of designing larger boron-based nanostructures starting from quasi-planar or fully planar building blocks.     

Iron, folic acid and vitamin B12 deficiencies related to anemia in adolescents from a region with a high incidence of congenital malformations in Venezuela

Since in recent years for certain age groups, the main cause of anemia is not iron deficiency, we intended to study the effect of iron, folic acid and vitamin B12 deficiencies on anemia prevalence in adolescents from Venezuela. One hundred adolescents aged between 12 and 19 years participated in the study. Each subject was interviewed about antecedents and habits and a physical examination and a 24-hour food recall questionnaire were performed. From a blood sample, hemoglobin and hematocrit concentrations were determined and serum was separated for quantification of ferritin, folic acid and vitamin B12 concentrations. Prevalence of anemia was 78% and for iron, folic acid and vitamin B12 deficiencies were 34.66, 90.9 and 18.18%, respectively. From anemic cases, 35.89% presented iron deficiency, while 91.02% presented folic acid deficiency. Only 19.23% of adolescents with anemia presented also vitamin B12 deficiency, but all the cases with vitamin B12 deficiency, were anemic. Simultaneous iron and folic acid deficiencies affected 30.76% of anemic cases. The high prevalence of deficiencies found in this work could be explained by insufficient intake and inadequate food habits. The prevalence of anemia was associated to folic acid deficiency rather than to iron deficiency, due to the high prevalence of folic acid deficiency. The high prevalence of nutritional deficiencies found in this work, especially regarding folic acid deficiency, require immediate interventions.     

Study on the dissolved oxygen control strategy in large‐scale vitamin B12 fermentation by Pseudomonas denitrificans

BACKGROUND: There are two different routes for vitamin B₁₂ biosynthesis, which results in discrepancies and uncertainties of the dissolved oxygen (DO) concentration for vitamin B₁₂ fermentation. In this paper, the DO control strategy was explored for industrial vitamin B₁₂ fermentation by Pesudomonas denitrificans in 120000‐L fermenter. RESULTS: A DO‐stat strategy was first successfully scaled up from a 9000 L fermenter to a 120 000 L fermenter. Then a multi‐stage DO control strategy was further established in the 120 000 L fermenter, in which the DO level was shifted from 8–10% (20–48 h) to 2–5% (49–106 h) and below 2% (107–168 h) by gradually reducing the rate of aeration and agitation. As a result, 198.80 mg L^?1 of vitamin B₁₂ was obtained, which was significantly higher than those obtained under the fermentations with one‐stage DO control. CONCLUSIONS: The comparatively low DO level was favorable for vitamin B₁₂ biosynthesis, but it would have an extremely negative effect on cell growth. Compared with the low DO level maintained at all times of the fermentation process, a multi‐stage DO control strategy could not only increase the biomass but also improve vitamin B₁₂ biosynthesis. Copyright © 2012 Society of Chemical Industry