ABSTRACT
The aim of this study was to determine the profile and contents of carotenoids, tocols and B1 and B2 vitamins in different parts of two wild edible plants (WEPs), Diplotaxis erucoides and Oxalis pes-caprae. Results showed interesting amounts of these bioactive compounds in the leaves, with intakes higher than the Recommended Daily Allowance (RDA) for vitamin A and vitamin E after consumption of 100 g. Diplotaxis erucoides and Oxalis pes-caprae leaves evidenced high amounts of carotenoids, such as lutein (about 8 mg/100 g and 5 mg, respectively) and ß-carotene (about 8 mg/100 g and 4 mg/100 g, respectively). Even when not present at high amounts, the investigated plants can also contribute to the daily intake of thiamine and riboflavin. The rich profile and high contents of bioactive compounds in these WEPs clearly justify their potential use as food ingredients in a healthy and sustainable modern cuisine and in the development of new functional foods.
Subject(s)
Carotenoids , Plant Leaves , Carotenoids/analysis , Plant Leaves/chemistry , Riboflavin/analysis , Thiamine/analysis , Plants, Edible/chemistry , Humans , Tocopherols/analysis , Lutein/analysis , Recommended Dietary Allowances , Nutritive ValueABSTRACT
Thiamine (vitamin B1) is an essential vitamin serving in its diphosphate form as a cofactor for enzymes in the citric acid cycle and pentose-phosphate pathways. Its concentration reported in the pM and nM range in environmental and clinical analyses prompted our consideration of the components used in pre-analytical processing, including the selection of filters, filter apparatuses, and sample vials. The seemingly innocuous use of glass fiber filters, glass filter flasks, and glass vials, ubiquitous in laboratory analysis of clinical and environmental samples, led to marked thiamine losses. 19.3 nM thiamine was recovered from a 100 nM standard following storage in glass autosampler vials and only 1 nM of thiamine was obtained in the filtrate of a 100 nM thiamine stock passed through a borosilicate glass fiber filter. We further observed a significant shift towards phosphorylated derivatives of thiamine when an equimolar mixture of thiamine, thiamine monophosphate, and thiamine diphosphate was stored in glass (most notably non-silanized glass, where a reduction of 54% of the thiamine peak area was observed) versus polypropylene autosampler vials. The selective losses of thiamine could lead to errors in interpreting the distribution of phosphorylated species in samples. Further, some loss of phosphorylated thiamine derivatives selectively to amber glass vials was observed relative to other glass vials. Our results suggest the use of polymeric filters (including nylon and cellulose acetate) and storage container materials (including polycarbonate and polypropylene) for thiamine handling. Losses to cellulose nitrate and polyethersulfone filters were far less substantial than to glass fiber filters, but were still notable given the low concentrations expected in samples. Thiamine losses were negated when thiamine was stored diluted in trichloroacetic acid or as thiochrome formed in situ, both of which are common practices, but not ubiquitous, in thiamine sample preparation.
Subject(s)
Glass , Thiamine , Thiamine/analysis , Thiamine/chemistry , Glass/chemistry , Adsorption , Humans , FiltrationABSTRACT
A protein hydrolysate of goat viscera added with xylose, cysteine, and thiamine under different pH was used to prepare a meat flavoring. Goat viscera hydrolysate and flavoring were subjected to analysis of physicochemical characteristics, amino acid profile, sugars, fatty acids, and volatile profile. Meat aroma characteristics were initiated in the hydrolysate, in which Strecker's pyrazines and aldehydes were identified, which also had fatty acids and amino acids available for the formation of 96 volatile compounds in the flavorings via lipid manipulation, Maillard occurrence, Strecker manipulation and interactions among these means. Maillard reaction products with intense meat aroma, such as 2-methyl-3-furanthiol, 2-furfurylthiol and, bis(2-methyl-3-furyl) disulfide were isolated only in the flavoring at pH 4. In contrast, the flavoring at pH 6 showed a higher concentration than all the other compounds, providing a lower meat characteristic, but an intense sweet, fatty and goat aroma.
Subject(s)
Cysteine , Maillard Reaction , Animals , Cysteine/chemistry , Thiamine/analysis , Xylose/chemistry , Protein Hydrolysates , Goats , Flavoring Agents/analysis , Meat/analysis , Fatty Acids , Odorants/analysisABSTRACT
The level of vitamin B group in human serum is an important index of human health. Among B vitamins, cyanocobalamin in serum is unstable and its content is extremely low. Rapid and simultaneous detection of multiple B vitamins including cyanocobalamin is a challenge. Herein, we have developed a rapid and stable method that can realize the determination of thiamine, riboflavin, nicotinamide, pantothenic acid, pyridoxic acid, biotin, 5-methyltetrahydrofolate, and cyanocobalamin simultaneously in 6 min. The method was established based on protein precipitation with methanol and then chromatographic separation was achieved using Waters acquity ultra-high-performance liquid chromatography high strength silica T3 column, which was stable and sensitive especially for cyanocobalamin. Limit of quantification, precision, trueness, and matrix effect were validated according to the European Medicines Agency and United States Food and Drug guidelines and Clinical and Laboratory Standards Institute guidelines on bioanalytical method. The limit of quantification for thiamine, riboflavin, nicotinamide, pantothenic acid, pyridoxic acid, biotin, 5-methyltetrahydrofolate, and cyanocobalamin was 0.4, 0.4, 0.8, 2.0, 0.4, 0.1, 0.4, and 0.04 ng/mL separately, respectively. Intra- and interday precisions were 1.1%-12.4% and 2.0%-13.5%, respectively. The relative errors were between 0.3% and 13.3%, and the matrix effects were between 2.6% and 10.4%.
Subject(s)
Vitamin B Complex , Humans , Pantothenic Acid/analysis , Biotin/analysis , Tandem Mass Spectrometry/methods , Pyridoxic Acid , Chromatography, Liquid/methods , Thiamine/analysis , Riboflavin/analysis , Niacinamide/analysis , Vitamin B 12/analysis , Chromatography, High Pressure Liquid/methods , Vitamin A/analysis , Vitamin K/analysisABSTRACT
BACKGROUND: High doses of oral thiamine improve clinical fatigue scores in patients with quiescent inflammatory bowel disease (IBD) and chronic fatigue. In this study we analysed plasma samples obtained in a randomised clinical trial and aimed compare levels of vitamins B1, B2, B3 and B6, and their related vitamers and metabolites in patients with IBD, with or without chronic fatigue and with or without effect of high dose oral thiamine for chronic fatigue. METHODS: Blood samples from patients with fatigue were drawn prior and after thiamine exposure and only once for patients without fatigue. A wide panel of analysis were done at Bevital AS Lab. RESULTS: Concentration of flavin mononucleotide (FMN) was lower in patients with chronic fatigue compared to patients without fatigue (p = 0.02). Patients with chronic fatigue who reported a positive effect on fatigue after 4 weeks of high dose thiamine treatment had a statistically significantly lower level of riboflavin after thiamine treatment (p = 0.01). CONCLUSION: FMN and Riboflavin were associated with chronic fatigue in patients with quiescent IBD. Levels of other B vitamins and metabolites were not significantly different between the investigated groups or related to effect of the thiamine intervention. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov study identifier NCT036347359. Registered 15 August 2018, https://clinicaltrials.gov/study/NCT03634735?cond=Inflammatory%20Bowel%20Diseases&intr=Thiamine&rank=1.
Subject(s)
Fatigue Syndrome, Chronic , Inflammatory Bowel Diseases , Vitamin B Complex , Humans , Vitamin B Complex/therapeutic use , Thiamine/therapeutic use , Thiamine/analysis , Riboflavin/therapeutic use , Riboflavin/analysis , Inflammatory Bowel Diseases/drug therapyABSTRACT
Although prime compounds in yeast metabolism, vitamins in oenology have remained mostly unexplored for decades. Here, a premier characterization of the vitamers in white grape musts has been drawn. A RP-HPLC method has therefore been developed for their direct analysis in musts, allowing for the determination of 19 different vitamers from 8 water-soluble vitaminic groups, including thiamine forms T, TMP and TPP, with LODs between 0.1 and 45.9 µg.L-1 and LOQs between 0.4 and 137.8 µg.L-1. A resulting characterization of 85 grape musts has been drawn from their vitaminic composition. Plus, the use of neither sulfites nor filtration affects the must vitamin content. The method stands as a useful tool for the later determination of yeast requirements, or impact of winemaking products on vitamins. The method has, overall, proven as practical and sensitive, for rapid identification of vitamins and vitamers in musts.
Subject(s)
Vitamins , Vitis , Chromatography, High Pressure Liquid/methods , Saccharomyces cerevisiae , Thiamine/analysis , Vitamin A/analysis , Vitamin K/analysis , Vitamins/analysisABSTRACT
B group vitamins, except folate, are involved in at least one step of cellular energy production. Vegetables are considered essential for a healthy diet plan. Vegetables significantly affect diet quality by contributing to the adequate intake of some B group vitamins. Our results demonstrated that the level of vitamins B1, B2, and B3 in the studied vegetables was in the range of 9-85 µg/100 g, 22-319 µg/100 g, and 459-3497 µg/100 g, respectively. However, it is fundamental to investigate the bioaccessibility of all vitamins to identify primary dietary sources. We observed that the average bioaccessibility values for vitamins B1 and B2 were 68.9% and 63.9%, respectively. The bioaccessibility of the nicotinic acid form of vitamin B3 was 40%, while the nicotinamide form was 33.9%. As revealed in this research, the bioaccessibilities of vitamins B1, B2, and B3 in vegetables were generally low in vitro.
Subject(s)
Thiamine , Vitamin B Complex , Diet , Folic Acid , Thiamine/analysis , VegetablesABSTRACT
The volatile composition and odor of meat and meat products is based on the precursors present in the raw meat. These are influenced by various pre-slaughter factors (species, breed, sex, age, feed, muscle type). Furthermore, post-mortem conditions (chiller aging, cooking conditions, curing, fermentation, etc.) determine the development of meat volatile organic compounds (VOCs). In this review, the main reactions leading to the development of meat VOCs such as the Maillard reaction; Strecker degradation; lipid oxidation; and thiamine, carbohydrate, and nucleotide degradation are described. The important pre-slaughter factors and post-mortem conditions influencing meat VOCs are discussed. Finally, the pros, cons, and future perspectives of the most commonly used sample preparation techniques (solid-phase microextraction, stir bar sorptive extraction, dynamic headspace extraction) and analytical methods (gas chromatography mass spectrometry and olfactometry, as well as electronic noses) for the analysis of meat VOCs are discussed, and the continued importance of sensorial analysis is pinpointed.
Subject(s)
Odorants , Volatile Organic Compounds , Carbohydrates , Lipids , Meat/analysis , Nucleotides , Odorants/analysis , Solid Phase Microextraction/methods , Thiamine/analysis , Volatile Organic Compounds/analysisABSTRACT
Thiamine is an essential vitamin for most living organisms, of which yeasts are a rich nutritional source. In this study we developed a thiamine extraction and determination method to detect thiamine in fresh yeast biomass. The thiamine determination method combines the derivatization of thiamine to a highly fluorescent product, with chromatographic separation (HPLC) and fluorescence detection. The method specifically detects free thiamine (T), thiamine phosphate (TP), and thiamine pyrophosphate (TPP). It has a high sensitivity of 2 ng/ml for TPP and TP, and 1 ng/ml for T, excellent instrumental repeatability, and low day-to-day variation in retention time of the different phosphate forms. We demonstrated the robustness of the method by proving that the fluorescence signals of the derivatised samples are stable for at least 82 h after derivatization, and by showing that the final pH of the samples does not influence the fluorescent response. In addition, we developed and validated a thiamine extraction method consisting of beads beating the fresh yeast biomass in 0.1 M HCl using a lysing matrix composed of 0.1 mm silica spheres. The performance of this method was compared to extraction via heat treatment at 95 °C for 30 min, and a combination of beads beating and heat treatment carried out in different order. We demonstrated that thiamine extraction via beads beating is the only method that prevents the biologically active form thiamine pyrophosphate to be degraded to thiamine phosphate, therefore, the extraction method developed and described in this study is preferred when the different thiamine vitamers need to be detected in their actual proportions. The combination of the extraction via beads beating, the conversion of all vitamers to the thiochrome derivatives, and the separation of these compounds on the reversed phase HPLC with a fluorescence detector, yielded a sensitive, specific, repeatable, and robust method for extraction and determination of vitamin B1 in fresh yeast biomass.
Subject(s)
Saccharomyces cerevisiae , Thiamine Pyrophosphate , Biomass , Chromatography, High Pressure Liquid/methods , Esters , Phosphates , Silicon Dioxide , Thiamine/analysis , Thiamine Monophosphate/analysis , Thiamine Pyrophosphate/analysis , VitaminsABSTRACT
Obligate symbiotic bacteria associated with the insects feeding exclusively on vertebrate blood are supposed to complement B vitamins presumably lacking in their diet. Recent genomic analyses revealed considerable differences in biosynthetic capacities across different symbionts, suggesting that levels of B vitamins may vary across different vertebrate hosts. However, a rigorous determination of B vitamins content in blood of various vertebrates has not yet been approached. A reliable analytical method focused on B vitamin complex in blood can provide valuable informative background and understanding of general principles of insect symbiosis. In this work, a chromatographic separation of eight B vitamins (thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, biotin, folic acid, and cyanocobalamine), four B vitamin derivatives (niacinamide, pyridoxal-5-phosphate, 4-pyridoxic acid, and tetrahydrofolic acid), and 3 stable isotope labelled internal standards was developed. Detection was carried out using dual-pressure linear ion trap mass spectrometer in FullScan MS/MS and SIM mode. Except for vitamin B9 (tetrahydrofolic acid), the instrument quantitation limits of all analytes were ranging from 0.42 to 5.0 µg/L, correlation coefficients from 0.9997 to 1.0000, and QC coefficients from 0.53 to 3.2%. Optimization of whole blood sample preparation step was focused especially on evaluation of two types of protein-precipitation agents: trichloroacetic acid and zinc sulphate in methanol. The best results were obtained for zinc sulphate in methanol, but only nine analytes were successfully validated. Accuracy of the procedure using this protein-precipitating agent was ranging from 89 to 120%, precision from 0.5 to 13%, and process efficiency from 65 to 108%. The content of B vitamins in whole blood samples from human and various vertebrates is presented as an application example of this newly developed method.
Subject(s)
Vitamin B Complex , Animals , Chromatography, Liquid/methods , Folic Acid/analysis , Humans , Methanol , Riboflavin/analysis , Tandem Mass Spectrometry/methods , Thiamine/analysis , Zinc SulfateABSTRACT
Recently, a novel hybrid surface technology (HST) has been developed to mitigate metal analyte adsorption in liquid chromatography. The HST provides a hybrid organic-inorganic surface on the metal fluidic path, from injection to detector and including the column frits and wall, to mitigate the interaction between analytes and metals. Here the impact of the HST on the analysis of B group vitamins using liquid chromatography coupled with electrospray tandem mass spectrometry (LC-ESI-MS/MS) has been evaluated. Significant improvements in analyte intensity, limit of quantification (LOQ), carry-over, and peak shape were observed using an LC-ESI-MS/MS system and column that incorporated the HST. The key observed improvements include a 3-10 times increase in sensitivity (providing a lower LOQ) for riboflavin, thiamine, nicotinamide, FMN, PLP, and 5MTHF, no carry-over, and a more symmetrical peak for thiamine. When applied to the analysis of B group vitamins in energy drinks and B vitamin dietary supplement samples, the HST system demonstrated excellent accuracy and repeatability.
Subject(s)
Vitamin B Complex , Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Technology , Thiamine/analysis , Vitamin B Complex/analysisABSTRACT
We report the synthesis of vitamin B1, B2, and B3 derived nucleotides and dinucleotides generated either through mechanochemical or solution phase chemistry. Under the explored conditions, adenosine and thiamine proved to be particularly amenable to milling conditions. Following optimization of the chemistry related to the formation pyrophosphate bonds, mixed dinucleotides of adenine and thiamine (vitamin B1), riboflavin (vitamin B2), nicotinamide riboside and 3-carboxamide 4-pyridone riboside (both vitamin B3 derivatives) were generated in good yields. Furthermore, we report an efficient synthesis of the MW+4 isotopologue of NAD+ for which deuterium incorporation is present on either side of the dinucleotidic linkage, poised for isotopic tracing experiments by mass spectrometry. Many of these mixed species are novel and present unexplored possibilities to simultaneously enhance or modulate cofactor transporters and enzymes of independent biosynthetic pathways.
Subject(s)
Niacin , Niacin/metabolism , Riboflavin , Thiamine/analysisABSTRACT
Nanofibers were fabricated by using the electrospinning technique. The diameter of gelatin nanofibers was measured as 41.511 nm. When thiamine was integrated into the nanofibers, it was increased to 100.156 nm. After raw red meat and salmon samples were coated with the nanofibers, the samples were stored at cold storage conditions. The thiamine levels of raw uncoated red meat (RM, 400 to 379 µg/100 g: p < 0.05) and salmon meat (SM, 68 to 62 µg/100 g: p < 0.05) were decreased. The coating increased thiamine contents in raw (519 to 563 µg/100 g) and cooked (416 to 485 µg/100 g) RM samples. Thiamine contents of raw (75 to 78 µg/100 g) and cooked (67 to 75 µg/100 g) SM samples were increased (p < 0.05). The changes in the bioaccessibility of uncoated and coated RM samples were in the range of 85-76%, and 87-79%, respectively while salmon samples were increased from 79 to 94% (p < 0.05).
Subject(s)
Nanofibers , Red Meat , Animals , Cooking , Meat/analysis , Salmon , Thiamine/analysisABSTRACT
The ability to measure the concentration of metabolites in biological samples is important, both in the clinic and for home diagnostics. Here we present a nanopore-based biosensor and automated data analysis for quantification of thiamine in urine in less than a minute, without the need for recalibration. For this we use the Cytolysin A nanopore and equip it with an engineered periplasmic thiamine binding protein (TbpA). To allow fast measurements we tuned the affinity of TbpA for thiamine by redesigning the π-π stacking interactions between the thiazole group of thiamine and TbpA. This substitution resulted furthermore in a marked difference between unbound and bound state, allowing the reliable discrimination of thiamine from its two phosphorylated forms by residual current only. Using an array of nanopores, this will allow the quantification within seconds, paving the way for next-generation single-molecule metabolite detection systems.
Subject(s)
Biosensing Techniques/methods , Body Fluids/chemistry , Nanopores , Thiamine/analysis , Carrier Proteins/chemistry , Carrier Proteins/metabolism , Electricity , Humans , Nanotechnology , Perforin/chemistry , Perforin/metabolism , Protein BindingABSTRACT
The nutritional composition and productivity of halophytes is strongly related to the biotic/abiotic stress to which these extremophile salt tolerant plants are subjected during their cultivation cycle. In this study, two commercial halophyte species (Inula crithmoides and Mesembryanthemum nodiflorum) were cultivated at six levels of salinity using a soilless cultivation system. In this way, it was possible to understand the response mechanisms of these halophytes to salt stress. The relative productivity decreased from the salinities of 110 and 200 mmol L-1 upwards for I. crithmoides and M. nodiflorum, respectively. Nonetheless, the nutritional profile for human consumption remained balanced. In general, I. crithmoides vitamin (B1 and B6) contents were significantly higher than those of M. nodiflorum. For both species, ß-carotene and lutein were induced by salinity, possibly as a response to oxidative stress. Phenolic compounds were more abundant in plants cultivated at lower salinities, while the antioxidant activity increased as a response to salt stress. Sensory characteristics were evaluated by a panel of culinary chefs showing a preference for plants grown at the salt concentration of 350 mmol L-1. In summary, salinity stress was effective in boosting important nutritional components in these species, and the soilless system promotes the sustainable and safe production of halophyte plants for human consumption.
Subject(s)
Inula/chemistry , Inula/growth & development , Mesembryanthemum/chemistry , Mesembryanthemum/growth & development , Nutritive Value , Salinity , Salt-Tolerant Plants/chemistry , Salt-Tolerant Plants/growth & development , Antioxidants/pharmacology , Diet, Vegetarian , Humans , Lutein/analysis , Minerals/analysis , Oxidative Stress , Phenols/analysis , Plant Extracts/pharmacology , Pyridoxine/analysis , Salt Stress , Tannins/analysis , Thiamine/analysis , beta Carotene/analysisABSTRACT
The use of substrates supplemented with minerals is a promising strategy for increasing the nutraceutical value of Pleurotus spp. The current research was performed to analyze the effect of substrate supplementation with magnesium (Mg) salts on the Mg content, biomass, and chemical composition of pink oyster mushroom (Pleurotus djamor) fruiting bodies. Before inoculation, substrate was supplemented with MgCl2 × 6 H2O and MgSO4, both salts were applied at three concentrations: 210, 420, and 4200 mg of Mg per 2 kg of substrate. The harvest period included three flushes. Substrate supplementation with 4200 mg of Mg caused the most significant decrease in mushroom productivity, of about 28% for both Mg salts. The dry matter content in fruiting bodies was significantly lower in the treatment in which 210 mg of Mg was applied as MgSO4 in comparison to the control. Supplementation effectively increased the Mg content in fruiting bodies of P. djamor by 19-85% depending on the treatment, and significantly affected the level of remaining bioelements and anions. One hundred grams of pink oyster fruiting bodies, supplemented with Mg salts, provides more than 20% of the Mg dietary value recommended by the Food and Drug Administration (FDA); thus, supplementation can be an effective technique for producing mushrooms that are rich in dietary Mg. Although P. djamor grown in supplemented substrate showed lower productivity, this was evident only in the fresh weight because the differences in dry weight were negligible. Mg supplementation increased the antioxidant activity of the fruiting bodies, phenolic compounds, and some amino acids, including L-tryptophan, and vitamins (thiamine and l-ascorbic acid).
Subject(s)
Dietary Supplements , Fruiting Bodies, Fungal/chemistry , Magnesium/chemistry , Pleurotus/metabolism , Agaricales , Ascorbic Acid/analysis , Ascorbic Acid/chemistry , Biofortification , Chlorides/chemistry , Culture Media , Food Technology , Functional Food , Phenol/chemistry , Phenols/chemistry , Pleurotus/chemistry , Salts/chemistry , Secale/microbiology , Sugars/chemistry , Sulfates/chemistry , Thiamine/analysis , Tryptophan/analysisABSTRACT
The contribution of free amino acids and thiamine to the production of potent meat aroma compounds in nitrite-reduced, dry-fermented sausages inoculated with a D. hansenii strain was the objective of this study. For this, three different sausage formulations were manufactured; a control and two formulations reduced by half in nitrate and nitrite and one of them inoculated with D. hansenii. Free amino acids, thiamine content and savoury volatile compounds were analysed. Eleven savoury volatile compounds were quantitated. Among them, the most potent compounds above their odour thresholds were 2-methyl-3-furanthiol, 2-acetyl-1-pyrroline, methional, dimethyl trisulfide and methyl-2-methyl-3-furyl disulfide. Their generation was affected by D. hansenii inoculation as shown by the decrease in methional and methyl 2-methyl-3-furyl disulfide content, and the increase of methionol. Nitrate and nitrite reduction did not significantly affect amino acid and thiamine contents.
Subject(s)
Amino Acids/analysis , Debaryomyces , Fermented Foods/analysis , Meat Products/analysis , Odorants/analysis , Aldehydes/analysis , Fermentation , Fermented Foods/microbiology , Meat Products/microbiology , Nitrates/metabolism , Nitrites/metabolism , Thiamine/analysis , Yeast, DriedABSTRACT
Two accurate and sensitive chromatographic methods have been introduced and validated for the simultaneous determination of thioctic acid, benfotiamine and cyanocobalamin in bulk powders and in their pharmaceutical formulation. Method A is reversed-phase ultra performance liquid chromatographic method with an isocratic elution, where a rapid separation was accomplished on a Zorbax C8 column using a mobile phase of acetonitrile:0.05 M phosphate buffer (pH 6 adjusted by o-phosphoric acid) (23:77, v/v). The retention times (tR) were 0.578, 0.852 and 1.376 for cyanocobalamin, benfotiamine and thioctic acid, respectively. The separated peaks were revealed at 210.0 nm. Method B is a thin-layer densitometric method where the separation of the studied drugs was carried out on silica gel plates using methanol-chloroform-heptane-1-sulphonic acid sodium salt (0.4%) (7:3:0.1, by volume) as a mobile phase, and scanning of the separated bands was done at 240.0 nm. The retardation factor (Rf) values were 0.17, 0.48 and 0.75 for cyanocobalamin, benfotiamine and thioctic acid, respectively. Validation of the methods was achieved following ICH guidelines and the applied methods succeeded to determine the cited drugs in their pure forms and capsules. Results were statistically compared to the manufacturer's method where no significant difference was observed.
Subject(s)
Thiamine/analysis , Thioctic Acid , Vitamin B 12/analysis , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Reproducibility of Results , Thiamine/analogs & derivatives , Thioctic Acid/analysisABSTRACT
Water-soluble vitamins are essential dietary components with a multitude of important functions that require quantification from food sources to characterise the nutritional status of food. In this study, we have developed a hydrophilic interaction chromatography (HILIC) based method coupled to single-quadrupole mass spectrometry (MS) for the analysis of selected water-soluble vitamins. Due to their involvement in energy release from macronutrients, the quantification of thiamine (B1), riboflavin (B2), nicotinamide (B3) and pyridoxine (B6) offers significant value in food analysis. A commercially available vegetable soup was selected as the food matrix for this study and utilised to develop an efficient extraction procedure for the vitamins of interest. Vitamins were extracted using meta-phosphoric acid coupled with a reducing agent, DL-dithiothreitol (DTT) to produce the parent compound. The extracted vitamins were then analysed using an LC-MS system with electrospray - atmospheric pressure ionization (ES-API) source, operated in positive single ion monitoring (SIM) mode. The MS provided good linearity within the investigated range from 5 to 400â¯ng/mL with coefficient of determination (r2) ranging from 0.98 to 0.99. Retention times (0.65-9.04 min) were reproducible and no coelution between vitamins was observed. Limit of detection (LOD) varied from 2.4 to 9.0â¯ng/mL and limit of quantification (LOQ) was from 8 to 30â¯ng/mL, comparable to previously published studies. The extraction method provided good intra-day (%CV 1.56-6.56) and inter-day precision (%CV 8.07-10.97). Standard injections were used as part of quality control measures and provided excellent reproducibility (%CV 0.9-3.4). The overall runtime of this method was 19 min, including column reconditioning. Using this method, the quantity of thiamine (67⯱â¯7â¯ng/g), riboflavin (423⯱â¯39â¯ng/g), nicotinamide (856⯱â¯77â¯ng/g) and pyridoxine (133⯱â¯11â¯ng/g) was determined from a complex food matrix. In conclusion, we have developed a rapid and reliable, HILIC-single quad MS method utilising SIM for the low-level quantification of four B vitamins in a vegetable soup matrix in under 20 min. This method has shown excellent linearity, intra- and inter-day reproducibility and is directly applicable to other plant-based food matrices.
Subject(s)
Chromatography, Liquid/methods , Food Analysis/methods , Mass Spectrometry/methods , Vitamins/analysis , Hydrophobic and Hydrophilic Interactions , Limit of Detection , Linear Models , Niacinamide/analysis , Pyridoxine/analysis , Reproducibility of Results , Riboflavin/analysis , Solubility , Thiamine/analysisABSTRACT
Component analysis plays an important role in food production, pharmaceutics and agriculture. Nanozymes have attracted wide attention in analytical applications for their enzyme-like properties. In this work, a fluorometric method is described for the determination of thiamine (TH) (vitamin B1) based on hemoglobin-Cu3(PO4)2 nanoflowers (Hb-Cu3(PO4)2 NFs) with peroxidase-like properties. The Hb-Cu3(PO4)2 NFs catalyzed the decomposition of H2O2 into ·OH radicals in an alkaline solution that could efficiently react with nonfluorescent thiamine to fluoresce thiochrome. The fluorescence of thiochrome was further enhanced with a nonionic surfactant, Tween 80. Under optimal reaction conditions, the linear range for thiamine was from 5 × 10-8 to 5 × 10-5 mol/L. The correlation coefficient for the calibration curve and the limit of detection (LOD) were 0.9972 and 4.8 × 10-8 mol/L, respectively. The other vitamins did not bring about any obvious changes in fluorescence. The developed method based on hybrid nanoflowers is specific, pragmatically simple and sensitive, and has potential for application in thiamine detection.