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Sathyan B, Banerjee G, Jagtap AA, Verma A, Cyriac J. Deep-Learning-Assisted Discriminative Detection of Vitamin B 12 and Vitamin B 9 by Fluorescent MoSe 2 Quantum Dots. ACS APPLIED BIO MATERIALS 2024; 7:1191-1203. [PMID: 38295366 DOI: 10.1021/acsabm.3c01072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
A facile and environmentally mindful approach for the synthesis of MoSe2 QDs was developed via the hydrothermal method from bulk MoSe2. In this, the exfoliation of MoSe2 was enhanced with the aid of an intercalation agent (KOH), which could reduce the exfoliation time and increase the exfoliation efficiency to form MoSe2 QDs. We found that MoSe2 QDs display blue emission that is suitable for different applications. This fluorescence property of MoSe2 QDs was harnessed to fabricate a dual-modal sensor for the detection of both vitamin B12 (VB12) and vitamin B9 (VB9), employing fluorescence quenching. We performed a detailed study on the fluorescence quenching mechanism of both analytes. The predominant quenching mechanism for VB12 is via Förster resonance energy transfer. In contrast, the recognition of VB9 primarily relies on the inner filter effect. We applied an emerging and captivating approach to pattern recognition, the deep-learning method, which enables machines to "learn" patterns through training, eliminating the need for explicit programming of recognition methods. This attribute endows deep-learning with immense potential in the realm of sensing data analysis. Here, analyzing the array-based sensing data, the deep-learning technique, "convolution neural networks", has achieved 93% accuracy in determining the contribution of VB12 and VB9.
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Affiliation(s)
- Bhasha Sathyan
- Department of Chemistry, Indian Institute of Space Science and Technology, Thiruvananthapuram, Kerala 695 547,India
| | - Gaurav Banerjee
- Department of Chemistry, Indian Institute of Space Science and Technology, Thiruvananthapuram, Kerala 695 547,India
| | - Ajinkya Ashok Jagtap
- Department of Chemistry, Indian Institute of Space Science and Technology, Thiruvananthapuram, Kerala 695 547,India
| | - Abhishek Verma
- Department of Chemistry, Indian Institute of Space Science and Technology, Thiruvananthapuram, Kerala 695 547,India
| | - Jobin Cyriac
- Department of Chemistry, Indian Institute of Space Science and Technology, Thiruvananthapuram, Kerala 695 547,India
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2
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Marques HM. The inorganic chemistry of the cobalt corrinoids - an update. J Inorg Biochem 2023; 242:112154. [PMID: 36871417 DOI: 10.1016/j.jinorgbio.2023.112154] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 01/23/2023] [Accepted: 01/26/2023] [Indexed: 02/05/2023]
Abstract
The inorganic chemistry of the cobalt corrinoids, derivatives of vitamin B12, is reviewed, with particular emphasis on equilibrium constants for, and kinetics of, their axial ligand substitution reactions. The role the corrin ligand plays in controlling and modifying the properties of the metal ion is emphasised. Other aspects of the chemistry of these compounds, including their structure, corrinoid complexes with metals other than cobalt, the redox chemistry of the cobalt corrinoids and their chemical redox reactions, and their photochemistry are discussed. Their role as catalysts in non-biological reactions and aspects of their organometallic chemistry are briefly mentioned. Particular mention is made of the role that computational methods - and especially DFT calculations - have played in developing our understanding of the inorganic chemistry of these compounds. A brief overview of the biological chemistry of the B12-dependent enzymes is also given for the reader's convenience.
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Affiliation(s)
- Helder M Marques
- Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg 2050, South Africa.
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Natural Deep Eutectic Solvent-Based Microwave-Assisted Extraction of Total Flavonoid Compounds from Spent Sweet Potato ( Ipomoea batatas L.) Leaves: Optimization and Antioxidant and Bacteriostatic Activity. Molecules 2022; 27:molecules27185985. [PMID: 36144716 PMCID: PMC9501105 DOI: 10.3390/molecules27185985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 09/07/2022] [Accepted: 09/08/2022] [Indexed: 11/17/2022] Open
Abstract
Natural deep eutectic solvents (NADESs) coupled with microwave-assisted extraction (MAE) were applied to extract total flavonoid compounds from spent sweet potato (Ipomoea batatas L.) leaves. In this study, ten different NADESs were successfully synthesized for the MAE. Based on single-factor experiments, the response surface methodology (RSM) was applied, and the microwave power, extraction temperature, extraction time, and solid−liquid ratio were further evaluated in order to optimize the yields of total flavonoid compounds. Besides, the extracts were recovered by macroporous resin for the biological activity detection of flavonoid compounds. As a result, NADES-2, synthesized by choline chloride and malic acid (molar ratio 1:2), exhibited the highest extraction yield. After that, the NADES-2-based MAE process was optimized and the optimal conditions were as follows: microwave power of 470 W, extraction temperature of 54 °C, extraction time of 21 min, and solid−liquid ratio of 70 mg/mL. The extraction yield (40.21 ± 0.23 mg rutin equivalents/g sweet potato leaves) of the model validation experiment was demonstrated to be in accordance with the predicted value (40.49 mg rutin equivalents/g sweet potato leaves). In addition, flavonoid compounds were efficiently recovered from NADES-extracts with a high recovery yield (>85%) using AB-8 macroporous resin. The bioactivity experiments in vitro confirmed that total flavonoid compounds had good DPPH and O2−· radical-scavenging activity, as well as inhibitory effects on E. coli, S. aureus, E. carotovora, and B. subtilis. In conclusion, this study provides a green and efficient method to extract flavonoid compounds from spent sweet potato leaves, providing technical support for the development and utilization of sweet potato leaves’ waste.
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Rampazzo G, Zironi E, Pagliuca G, Gazzotti T. Analysis of Cobalamin (Vit B12) in Ripened Cheese by Ultra-High-Performance Liquid Chromatography Coupled with Mass Spectrometry. Foods 2022; 11:foods11182745. [PMID: 36140873 PMCID: PMC9497947 DOI: 10.3390/foods11182745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 09/03/2022] [Accepted: 09/05/2022] [Indexed: 11/16/2022] Open
Abstract
The analysis of natural cobalamins in dairy products still represents an analytical challenge. The matrix’s complexity, low concentration level, light sensitivity, and binding to proteins are just some of the aspects that make their quantification a difficult goal to achieve. Vitamin B12 plays a fundamental role in human nutrition, and its intake is closely linked to a diet that includes the consumption of food of animal origin. In the current literature, few studies have been carried out on the quantitation of cobalamin in ripened cheeses. A sensitive, selective, and robust ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) method was developed, validated, and applied on ripened cheeses from different species (cow, sheep, and goat) purchased from local Italian markets, highlighting species-dependent differences in vitamin B12 concentrations. The vitamin B12 extraction procedure was performed by converting all cobalamins to the cyanocobalamin form. Furthermore, solid-phase extraction was used for matrix clean-up and analyte preconcentration. The proposed method showed good performance in terms of linearity, sensitivity, reproducibility, and repeatability. The mean vitamin B12 content ranged from <LOQ to 38.9 ng/g. Sheep cheese showed the highest concentrations of vitamin B12, with a mean content of 29.0 ng/g.
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Affiliation(s)
- Giulia Rampazzo
- Department of Veterinary Medical Science, Alma Mater Studiorum University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell’Emilia, Italy
| | - Elisa Zironi
- Department of Veterinary Medical Science, Alma Mater Studiorum University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell’Emilia, Italy
| | - Giampiero Pagliuca
- Department of Veterinary Medical Science, Alma Mater Studiorum University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell’Emilia, Italy
- Health Sciences and Technologies-Interdepartmental Centre for Industrial Research (CIRI-SDV), University of Bologna, 40064 Ozzano dell’Emilia, Italy
- Correspondence:
| | - Teresa Gazzotti
- Department of Veterinary Medical Science, Alma Mater Studiorum University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell’Emilia, Italy
- Health Sciences and Technologies-Interdepartmental Centre for Industrial Research (CIRI-SDV), University of Bologna, 40064 Ozzano dell’Emilia, Italy
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Hossain MN, Senaka Ranadheera C, Fang Z, Ajlouni S. Production of short chain fatty acids and vitamin B12 during the in-vitro digestion and fermentation of probiotic chocolate. FOOD BIOSCI 2022. [DOI: 10.1016/j.fbio.2022.101682] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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6
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Rego A, Coelho I, Motta C, Cardoso C, Gomes-Bispo A, Afonso C, Prates J, Bandarra N, Silva J, Castanheira I. Seasonal variation of chub mackerel (Scomber colias) selenium and vitamin B12 content and its potential role in human health. J Food Compost Anal 2022. [DOI: 10.1016/j.jfca.2022.104502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Zahed O, Khosravi-Darani K, Mortazavian AM, Mohammadi A. Effects of cultivation conditions on biofortification of yogurt with natural folate by Propionibacterium freudenreichii. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2022. [DOI: 10.1016/j.bcab.2021.102267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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8
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Altunay N, Elik A, Aydın D. Feasibility of supramolecular nanosized solvent based microsyringe-assisted liquid-phase microextraction for preconcentration and separation of Vitamin B12 from infant formula, food supplement, and dairy products: Spectrophotometric analysis and chemometric optimization. Microchem J 2021. [DOI: 10.1016/j.microc.2021.106105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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HPLC Quantification of Thymoquinone Extracted from Nigella sativa L. ( Ranunculaceae) Seeds and Antibacterial Activity of Its Extracts against Bacillus Species. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2021; 2021:6645680. [PMID: 33986821 PMCID: PMC8079179 DOI: 10.1155/2021/6645680] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 02/21/2021] [Accepted: 04/03/2021] [Indexed: 11/17/2022]
Abstract
The medicinal importance of Nigella sativa seeds for treating various ailments is portrayed by its traditional uses. Owing to its immense pharmacological importance, the thymoquinone phytoconstituent of N. sativa can prove beneficial for the South Asian countries including Pakistan, where this seed is commonly produced and healthcare facilities are limited. In this study, the antibacterial activity of various extracts of N. sativa seeds, extracted thymoquinone, and oil samples have been investigated against Bacillus subtilis and Bacillus licheniformis using well and disc diffusion assay. The inhibition zones ranged between 7 and 44 mm against both the bacterial strains by well diffusion assay, while disc diffusion assay provided inhibition zones in the range of 7–23 mm. Commercial and local Kalonji oil samples were included in the study. Oil samples dissolved in methanol showed increased inhibition of bacteria. However, the extracted thymoquinone showed highest antibacterial activity. Medicine formulated using thymoquinone will prove to be an herbal alternate against the resistant microbiota associated with bacterial infections. Antibacterial activity against some Bacillus species will help signify the effect on normal gut flora when oral therapy is followed. Trying different extraction protocols can help increase extraction efficiency. Study on extraction of thymoquinone in local produce of black seed can be fruitful for conducting the stability studies and can help to gain maximum benefits from the bioactives. The crude extracts from 10 g of these seeds were subjected to preliminary phytochemical investigation. Results showed that although methanol extract had the presence of maximum phytochemicals, hexane extract was the most potent in terms of antibacterial activity. Thymoquinone, a therapeutically important bioactive in N. sativa seed, was extracted employing both solvents. TLC assay and UV spectroscopy were used for its qualitative assessment, while HPLC-UV quantification showed that 250 mg/mL of methanol extract had 368.3 μg/mL thymoquinone, while its successive extraction yielded 32.94 μg/mL thymoquinone.
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Electrochemical sensors as a versatile tool for the quantitative analysis of Vitamin B12. CHEMICAL PAPERS 2021. [DOI: 10.1007/s11696-021-01574-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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11
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Bodur S, Erarpat S, Balçık U, Bakırdere S. A rapid, sensitive and accurate determination of cobalamin with double monitoring system: HPLC-UV and HPLC-ICP-OES. Food Chem 2020; 340:127945. [PMID: 32889200 DOI: 10.1016/j.foodchem.2020.127945] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 08/16/2020] [Accepted: 08/24/2020] [Indexed: 11/15/2022]
Abstract
This study proposed a novel analytical method for the separation and determination of cobalamin and cobalt in kefir samples by high performance liquid chromatography-inductively coupled plasma-optical emission spectrometry (HPLC-ICP-OES) in addition to determination of cobalamin in HPLC system. Chromatographic parameters such as column type, buffer solution, mobile phase flow rate and sample injection volume were individually studied and optimized. In addition, cobalamin was simultaneously determined by high performance liquid chromatography with ultraviolet detection (HPLC-UV). LOD values of cobalt in cobalamin and cobalt for HPLC-ICP-OES system were calculated as 0.07 mg/kg (as Co) and 0.06 mg/kg, respectively. Recovery studies were conducted to evaluate the accuracy/applicability of the method. Recovery results for cobalt in cobalamin and cobalt detected by the HPLC-ICP-OES system were calculated in the range of 87.4-100.1 and 98.8-115.0%, respectively while recovery results for cobalamin were found to be between 89.2 and 98.3% for HPLC-UV system.
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Affiliation(s)
- Süleyman Bodur
- Yıldız Technical University, Faculty of Art and Science, Department of Chemistry, 34220 Davutpasa, Esenler, İstanbul, Turkey
| | - Sezin Erarpat
- Yıldız Technical University, Faculty of Art and Science, Department of Chemistry, 34220 Davutpasa, Esenler, İstanbul, Turkey
| | - Utku Balçık
- Yıldız Technical University, Faculty of Art and Science, Department of Chemistry, 34220 Davutpasa, Esenler, İstanbul, Turkey
| | - Sezgin Bakırdere
- Yıldız Technical University, Faculty of Art and Science, Department of Chemistry, 34220 Davutpasa, Esenler, İstanbul, Turkey; Turkish Academy of Sciences (TÜBA), Piyade Sokak No: 27, Çankaya, 06690 Ankara, Turkey.
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12
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Hedayati R, Hosseini M, Najafpour GD. Optimization of semi-anaerobic vitamin B12 (cyanocobalamin) production from rice bran oil using Propionibacterium freudenreichii PTCC1674. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2020. [DOI: 10.1016/j.bcab.2019.101444] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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13
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Fatima Z, Jin X, Zou Y, Kaw HY, Quinto M, Li D. Recent trends in analytical methods for water-soluble vitamins. J Chromatogr A 2019; 1606:360245. [PMID: 31122728 DOI: 10.1016/j.chroma.2019.05.025] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/30/2019] [Accepted: 05/13/2019] [Indexed: 12/28/2022]
Abstract
In this review, recent advances in the analysis of water-soluble vitamins (WSVs) have been reported considering the advantages and disadvantages of various extraction, separation and detection techniques, commonly used for their quantification. Acid hydrolysis, enzyme treatment, SPE based methods and some other extraction methods have been discussed. Particular attention has been devoted to the analytical techniques based on liquid chromatography and electrophoresis. Furthermore, suitability and selectivity of hydrophilic interaction liquid chromatography (HILIC) for WSVs has been discussed in detail. Problems related to these techniques and their possible solutions have also been considered. Special focus has been given to the applications of liquid chromatography (since 2014-2019) for the simultaneous analysis of WSVs and their homologous in complex food samples.
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Affiliation(s)
- Zakia Fatima
- Department of Chemistry, MOE Key Laboratory of Natural Resources of the Changbai Mountain and Functional Molecules, Yanbian University, Park Road 977, Yanji 133002, Jilin Province, PR China
| | - Xiangzi Jin
- Department of Chemistry, MOE Key Laboratory of Natural Resources of the Changbai Mountain and Functional Molecules, Yanbian University, Park Road 977, Yanji 133002, Jilin Province, PR China
| | - Yilin Zou
- Department of Chemistry, MOE Key Laboratory of Natural Resources of the Changbai Mountain and Functional Molecules, Yanbian University, Park Road 977, Yanji 133002, Jilin Province, PR China
| | - Han Yeong Kaw
- Department of Chemistry, MOE Key Laboratory of Natural Resources of the Changbai Mountain and Functional Molecules, Yanbian University, Park Road 977, Yanji 133002, Jilin Province, PR China
| | - Maurizio Quinto
- Department of Chemistry, MOE Key Laboratory of Natural Resources of the Changbai Mountain and Functional Molecules, Yanbian University, Park Road 977, Yanji 133002, Jilin Province, PR China; SAFE - Department of Science of Agriculture, Food and Environment, University of Foggia, via Napoli 25, I-71100 Foggia, Italy
| | - Donghao Li
- Department of Chemistry, MOE Key Laboratory of Natural Resources of the Changbai Mountain and Functional Molecules, Yanbian University, Park Road 977, Yanji 133002, Jilin Province, PR China.
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Hadinata Lie A, V Chandra-Hioe M, Arcot J. Sorbitol enhances the physicochemical stability of B 12 vitamers. INT J VITAM NUTR RES 2019; 90:439-447. [PMID: 30932778 DOI: 10.1024/0300-9831/a000578] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The stability of B12 vitamers is affected by interaction with other water-soluble vitamins, UV light, heat, and pH. This study compared the degradation losses in cyanocobalamin, hydroxocobalamin and methylcobalamin due to the physicochemical exposure before and after the addition of sorbitol. The degradation losses of cyanocobalamin in the presence of increasing concentrations of thiamin and niacin ranged between 6%-13% and added sorbitol significantly prevented the loss of cyanocobalamin (p<0.05). Hydroxocobalamin and methylcobalamin exhibited degradation losses ranging from 24%-26% and 48%-76%, respectively; added sorbitol significantly minimised the loss to 10% and 20%, respectively (p < 0.05). Methylcobalamin was the most susceptible to degradation when co-existing with ascorbic acid, followed by hydroxocobalamin and cyanocobalamin. The presence of ascorbic acid caused the greatest degradation loss in methylcobalamin (70%-76%), which was minimised to 16% with added sorbitol (p < 0.05). Heat exposure (100 °C, 60 minutes) caused a greater loss of cyanocobalamin (38%) than UV exposure (4%). However, degradation losses in hydroxocobalamin and methylcobalamin due to UV and heat exposures were comparable (>30%). At pH 3, methylcobalamin was the most unstable showing 79% degradation loss, which was down to 12% after sorbitol was added (p < 0.05). The losses of cyanocobalamin at pH 3 and pH 9 (~15%) were prevented by adding sorbitol. Addition of sorbitol to hydroxocobalamin at pH 3 and pH 9 reduced the loss by only 6%. The results showed that cyanocobalamin was the most stable, followed by hydroxocobalamin and methylcobalamin. Added sorbitol was sufficient to significantly enhance the stability of cobalamins against degradative agents and conditions.
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Affiliation(s)
| | | | - Jayashree Arcot
- Food and Health Cluster, School of Chemical Engineering, Australia
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Ultra-high performance liquid chromatographic and mass spectrometric analysis of active vitamin B12 in cells of Propionibacterium and fermented cereal matrices. Food Chem 2015; 166:630-638. [DOI: 10.1016/j.foodchem.2014.06.068] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 06/04/2014] [Accepted: 06/15/2014] [Indexed: 12/22/2022]
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16
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Zironi E, Gazzotti T, Barbarossa A, Devicienti C, Scardilli M, Pagliuca G. Technical note: development and validation of a method using ultra performance liquid chromatography coupled with tandem mass spectrometry for determination of vitamin B12 concentrations in milk and dairy products. J Dairy Sci 2013; 96:2832-6. [PMID: 23497990 DOI: 10.3168/jds.2012-6451] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 01/12/2013] [Indexed: 11/19/2022]
Abstract
A method using ultra performance liquid chromatography coupled with tandem mass spectrometry was developed to measure cobalamins in naturally enriched raw milk and to evaluate their fate during thermal treatments and along the process of cheese making. After addition of methotrexate as internal standard, samples were submitted to heat treatment in the presence of cyanide, which converts all the less-stable cobalamins into cyanocobalamin; then, purification was performed by a solid-phase extraction step. Reverse-phase ultra performance liquid chromatography separation coupled with tandem mass spectrometry provided a fast and reliable determination. Mass spectrometric analysis was carried out in multiple reaction monitoring mode. The monitored transitions were m/z 678.36 → 147.10 and 678.36 → 359.30 for vitamin B12 and m/z 455.22 → 175.13 and 455.22 → 308.22 for methotrexate (internal standard). The limit of quantification was 2 ng/g. The method showed good linearity from 2 to 20 ng/g (R(2) ≥ 0.98) and intra- and interday precisions were always less than 19%.
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Affiliation(s)
- E Zironi
- Laboratory of Analytical Bio-Agroalimentary Chemistry (CABA-Lab), Department of Veterinary Medical Sciences, Alma Mater Studiorum - University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano Emilia (BO), Italy
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17
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Berton P, Monasterio RP, Wuilloud RG. Selective extraction and determination of vitamin B12 in urine by ionic liquid-based aqueous two-phase system prior to high-performance liquid chromatography. Talanta 2012; 97:521-6. [DOI: 10.1016/j.talanta.2012.05.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 05/07/2012] [Accepted: 05/08/2012] [Indexed: 11/26/2022]
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18
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Thirupathaiah Y, Swarupa Rani C, Sudhakara Reddy M, Venkateswar Rao L. Effect of chemical and microbial vitamin B₁₂ analogues on production of vitamin B₁₂. World J Microbiol Biotechnol 2012; 28:2267-71. [PMID: 22806050 DOI: 10.1007/s11274-012-1011-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2011] [Accepted: 01/28/2012] [Indexed: 10/14/2022]
Abstract
Strain improvement by genetic manipulation or optimization of fermentation conditions for overproduction of vitamin B(12) has a drawback due to feed back inhibition. To resist the feed back inhibition by analogues of vitamin B(12) in Propionibacterium freudenrechii subsps. shermanii (OLP-5), we have tested with microbially separated B(12) analogues from three different strains. Microbial analogues were differentiated from commercially available vitamin B(12) by high pressure liquid chromatography and spectrophotometric method. An analogue isolated from NRRL-B-4327 was shown to increase vitamin B(12) concentration from 18.53 ± 0.15 to 31.67 ± 0.58 mg/l in OLP-5 strain. The presence of chemical analogue (ICH(2) Co(DH)(2) (H(2)Py)(4)) increased vitamin B(12) production from 16.13 ± 0.15 to 18.53 ± 0.15 mg/l in OLP-5. These findings revealed that addition of B(12) analogues in fermentation media have developed strain resistance to feed back inhibition by vitamin B(12).
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Affiliation(s)
- Yeruva Thirupathaiah
- Department of Microbiology, Osmania University, Hyderabad 500007, Andhra Pradesh, India
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19
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Optimisation of vitamin B12 and folate production by Propionibacterium freudenreichii strains in kefir. Int Dairy J 2011. [DOI: 10.1016/j.idairyj.2010.09.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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