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Timkina E, Jarošová Kolouchová I, Kyselová L, Palyzová A, Murphy DJ, Řezanka T. Off-line two-dimensional LC-tandem MS of menaquinones from thermophilic bacteria. Food Chem 2024; 431:137112. [PMID: 37572480 DOI: 10.1016/j.foodchem.2023.137112] [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] [Received: 04/04/2023] [Revised: 07/28/2023] [Accepted: 08/04/2023] [Indexed: 08/14/2023]
Abstract
Thermophilic bacteria of four genera in contrast to the commonly used production strains such as Bacillus subtilis, produce homologs other than menaquinone (MK) with seven isoprene units. The number of isoprene units and the configuration of double bonds are essential factors for their biological activity. The goal was to obtain a strain of bacteria that produces a wide range of MK homologs and only all-trans geometrical isomers, which was the strain G. kaustophilus. Using off-line two-dimensional LC-tandem MS in columns with the RP18 phase and the COSMOSIL cholester phase (separation according to the geometric configuration of double bonds) it was shown that thermophilic bacteria grown at different temperatures produce only all-trans isomers of menaquinones from MK-5 (menaquinone with five isoprenyl units) to MK-15 (fifteen isoprenyl units). Therefore, G. kaustophilus appears to be a biotechnologically important strain produces only trans isomers and additionally homologs from 5 to 15 isoprene units.
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Affiliation(s)
- Elizaveta Timkina
- Department of Biotechnology, University of Chemistry and Technology, Technická 5, 166 28 Prague, Czech Republic
| | - Irena Jarošová Kolouchová
- Department of Biotechnology, University of Chemistry and Technology, Technická 5, 166 28 Prague, Czech Republic
| | - Lucie Kyselová
- Research Institute of Brewing and Malting, Lípová 511, 120 44 Prague, Czech Republic
| | - Andrea Palyzová
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 00 Prague, Czech Republic
| | - Denis J Murphy
- School of Applied Sciences, University of South Wales, Pontypridd CF37 1DL, UK
| | - Tomáš Řezanka
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 00 Prague, Czech Republic.
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Paprotny Ł, Szewczak D, Bryshten I, Wianowska D. Development, Validation, and Two-Year Application of Rapid and Simple LC-MS/MS-Based Method for the Determination of K2MK-7 in Blood Samples. Molecules 2023; 28:6523. [PMID: 37764299 PMCID: PMC10535264 DOI: 10.3390/molecules28186523] [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] [Received: 08/09/2023] [Revised: 08/31/2023] [Accepted: 09/01/2023] [Indexed: 09/29/2023] Open
Abstract
Biological properties of menaquinone-7, one of the vitamin K2 vitamers (K2MK-7), both those proven and those that remain to be investigated, arouse extensive interest that goes beyond the strictly scientific framework. The most important of them is the prevention of age-related diseases, considering that we live in the times identified as the era of aging societies and many people are exposed to the vitamin K2MK-7 deficiency. Therefore, an effective analytical protocol that can be adopted as a diagnostic and preventive analytics tool is needed. Herein, a simple sample preparation method followed by the liquid chromatography-tandem mass spectrometry-based method (LC-MS/MS), was used for the selective and sensitive determination of K2MK-7 in serum samples. Under the optimized conditions, using 500 µL of serum and the same amount of n-hexane, the reproducibility and the accuracy were obtained in the ranges of 89-97% and 86-110%, respectively, and the limit of detection value was 0.01 ng/mL. This method was used for the routine analysis. Statistical interpretation of the data from 518 samples obtained during 2 years of practice allowed for obtaining information on the content and distribution of K2MK-7 in the Polish population, broken down by the sex and age groups.
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Affiliation(s)
- Łukasz Paprotny
- ALAB Laboratories, Research and Development Centre, ul. Ceramiczna 1, 20-150 Lublin, Poland (D.S.)
| | - Dorota Szewczak
- ALAB Laboratories, Research and Development Centre, ul. Ceramiczna 1, 20-150 Lublin, Poland (D.S.)
| | - Iryna Bryshten
- Department of Chromatography, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University in Lublin, Pl. Maria Curie-Skłodowska 3, 20-031 Lublin, Poland
| | - Dorota Wianowska
- Department of Chromatography, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University in Lublin, Pl. Maria Curie-Skłodowska 3, 20-031 Lublin, Poland
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Lal N, Seifan M, Ebrahiminezhad A, Berenjian A. The Impact of Amine-Functionalised Iron Oxide Nanoparticles on the Menaquinone-7 Isomer Profile and Production of the Bioactive Isomer. Mol Biotechnol 2023:10.1007/s12033-023-00832-w. [PMID: 37517081 DOI: 10.1007/s12033-023-00832-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 07/13/2023] [Indexed: 08/01/2023]
Abstract
The K family of vitamins includes a collection of molecules with different pharmacokinetic characteristics. Menaquinone-7 (MK-7) has the finest properties and is the most therapeutically beneficial due to its long plasma half-life and outstanding extrahepatic bioavailability. MK-7 exhibits cis-trans isomerism, and merely the all-trans form is biologically efficacious. Therefore, the remedial value of MK-7 end products is exclusively governed by the quantity of all-trans MK-7. Consumers favour fermentation for the production of MK-7; however, it involves several challenges. The low MK-7 yield and extensive downstream processing requirements increase production costs, resulting in an expensive final product that is not universally available. Bacterial cell immobilisation with iron oxide nanoparticles (IONs) can potentially address the limitations of MK-7 fermentation. Uncoated IONs tend to have low stability and can adversely affect cell viability; thus, amine-functionalised IONs, owing to their increased physicochemical stability and biocompatibility, are a favourable alternative. Nonetheless, employing biocompatible IONs for this purpose is only advantageous if the bioactive MK-7 isomer is obtained in the most significant fraction, exploring which formed the aim of this investigation. Two amine-functionalised IONs, namely 3-aminopropyltriethoxysilane (APTES)-coated IONs (IONs@APTES) and L-Lysine (L-Lys)-coated IONs (L-Lys@IONs), were synthesised and characterised, and their impact on various parameters was evaluated. IONs@APTES were superior, and the optimal concentration (300 [Formula: see text]g/mL) increased all-trans MK-7 production and improved its yield relative to the untreated cells by 2.3- and 3.1-fold, respectively. The outcomes of this study present an opportunity to develop an innovative and effective fermentation method that enhances the production of bioactive MK-7.
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Affiliation(s)
- Neha Lal
- School of Engineering, The University of Waikato, Hamilton, 3240, New Zealand
| | - Mostafa Seifan
- School of Engineering, The University of Waikato, Hamilton, 3240, New Zealand
| | | | - Aydin Berenjian
- School of Engineering, The University of Waikato, Hamilton, 3240, New Zealand.
- Department of Chemical and Biological Engineering, Colorado State University, Fort Collins, CO, 80523, USA.
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Lal N, Seifan M, Ebrahiminezhad A, Berenjian A. The Effect of Iron Oxide Nanoparticles on the Menaquinone-7 Isomer Composition and Synthesis of the Biologically Significant All- Trans Isomer. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:1825. [PMID: 37368255 DOI: 10.3390/nano13121825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 06/28/2023]
Abstract
Menaquinone-7 (MK-7) is the most therapeutically valuable K vitamin owing to its excellent bioavailability. MK-7 occurs as geometric isomers, and only all-trans MK-7 is bioactive. The fermentation-based synthesis of MK-7 entails various challenges, primarily the low fermentation yield and numerous downstream processing steps. This raises the cost of production and translates to an expensive final product that is not widely accessible. Iron oxide nanoparticles (IONPs) can potentially overcome these obstacles due to their ability to enhance fermentation productivity and enable process intensification. Nevertheless, utilisation of IONPs in this regard is only beneficial if the biologically active isomer is achieved in the greatest proportion, the investigation of which constituted the objective of this study. IONPs (Fe3O4) with an average size of 11 nm were synthesised and characterised using different analytical techniques, and their effect on isomer production and bacterial growth was assessed. The optimum IONP concentration (300 μg/mL) improved the process output and resulted in a 1.6-fold increase in the all-trans isomer yield compared to the control. This investigation was the first to evaluate the role of IONPs in the synthesis of MK-7 isomers, and its outcomes will assist the development of an efficient fermentation system that favours the production of bioactive MK-7.
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Affiliation(s)
- Neha Lal
- School of Engineering, The University of Waikato, Hamilton 3240, New Zealand
| | - Mostafa Seifan
- School of Engineering, The University of Waikato, Hamilton 3240, New Zealand
| | - Alireza Ebrahiminezhad
- Biotechnology Research Center, Shiraz University of Medical Sciences, Shiraz P.O. Box 71348-14336, Iran
| | - Aydin Berenjian
- School of Engineering, The University of Waikato, Hamilton 3240, New Zealand
- Department of Chemical and Biological Engineering, Colorado State University, Fort Collins, CO 80523, USA
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The impact of key fermentation parameters on the production of the all-trans isomer of menaquinone-7. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2022. [DOI: 10.1016/j.bcab.2022.102548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Wianowska D, Bryshten I. New Insights into Vitamin K-From Its Natural Sources through Biological Properties and Chemical Methods of Quantitative Determination. Crit Rev Anal Chem 2022:1-23. [PMID: 36083712 DOI: 10.1080/10408347.2022.2121599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Vitamin K is one of the many health-promoting substances whose impact on the human body has been underestimated until recently. However, recently published research results have changed this situation, prompting some researchers to consider it a new panacea for diseases of old age. The result is a significant increase in interest in the accurate analysis of vitamin K in various types of samples, ranging from food, through dietary supplements, to biological matrices and clinical trials, both observational and interventional. This review summarizes the current state of knowledge about the proven and speculated biological activity of vitamin K and its importance for the world's aging societies, including the methods used for its isolation and analysis in various matrices types. Of all the analytical methods, the currently preferred methods of choice for the direct analysis of vitamin K are chromatographic methods, in particular liquid chromatography-tandem mass spectrometry. This technique, despite its sensitivity and selectivity, requires an appropriate stage of sample preparation. As there is still room for improvement in the efficiency of these methods, especially at the sample preparation stage, this review shows the directions that need to be taken to make these methods faster, more efficient and more environmentally friendly.
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Affiliation(s)
- Dorota Wianowska
- Department of Chromatography, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University in Lublin, Lublin, Poland
| | - Iryna Bryshten
- Department of Chromatography, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University in Lublin, Lublin, Poland
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Lal N, Seifan M, Berenjian A. Optimisation of the fermentation media to enhance the production of the bioactive isomer of vitamin menaquinone-7. Bioprocess Biosyst Eng 2022; 45:1371-1390. [PMID: 35864383 PMCID: PMC9302956 DOI: 10.1007/s00449-022-02752-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 06/22/2022] [Indexed: 11/30/2022]
Abstract
Menaquinone-7 (MK-7) offers significant health benefits; however, only the all-trans form is biologically active. MK-7 produced through fermentation can occur as all-trans and cis isomers, and the therapeutic value of the resulting MK-7 is exclusively determined by the quantity of the all-trans isomer. Therefore, this study aimed to investigate the effect of the media composition on the isomer profile obtained from fermentation and determine the optimum media combination to increase the concentration of the all-trans isomer and diminish the production of cis MK-7. For this purpose, design of experiments (DOE) was used to screen the most effective nutrients, and a central composite face-centred design (CCF) was employed to optimise the media components. The optimum media consisted of 1% (w/v) glucose, 2% (w/v) yeast extract, 2% (w/v) soy peptone, 2% (w/v) tryptone, and 0.1% (w/v) CaCl2. This composition resulted in an average all-trans and cis isomer concentration of 36.366 mg/L and 1.225 mg/L, respectively. In addition, the optimised media enabled an all-trans isomer concentration 12.2-fold greater and a cis isomer concentration 2.9-fold less than the unoptimised media. This study was the first to consider the development of an optimised fermentation media to enhance the production of the bioactive isomer of MK-7 and minimise the concentration of the inactive isomer. Furthermore, this media is commercially promising, as it will improve the process productivity and reduce the costs associated with the industrial fermentation of the vitamin.
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Affiliation(s)
- Neha Lal
- School of Engineering, The University of Waikato, Hamilton, 3240, New Zealand
| | - Mostafa Seifan
- School of Engineering, The University of Waikato, Hamilton, 3240, New Zealand
| | - Aydin Berenjian
- School of Engineering, The University of Waikato, Hamilton, 3240, New Zealand. .,Department of Agricultural and Biological Engineering, Pennsylvania State University, 221 Agricultural Engineering Building, University Park, PA, 16802, USA.
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Bus K, Sitkowski J, Bocian W, Zmysłowski A, Ofiara K, Szterk A. Separation of menaquinone-7 geometric isomers by semipreparative high-performance liquid chromatography with silver complexation and identification by nuclear magnetic resonance. Food Chem 2022; 368:130890. [PMID: 34438182 DOI: 10.1016/j.foodchem.2021.130890] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 07/21/2021] [Accepted: 08/14/2021] [Indexed: 11/04/2022]
Abstract
Dietary supplements containing vitamin K2 are often used to prevent osteoporosis, vascular calcification and coronary heart disease. It has been shown that some of these products contain a mixture of menaquinone-7 geometric isomers. Since the geometric shape may influence biological activity, there was a need for a semipreparative method to isolate single compounds for further studies. Here, we present an argentation chromatographic method for the separation of menaquinone-7 isomers and an nuclear magnetic resonance (NMR) methodology for the configuration assignment of isoprenoid side chain. The DFT calculations were performed to determine more energetically favorable complexes between the cis or trans menaquinone-7 isomers and the silver cation. Seventeen components were resolved, and fractions were collected and subjected to NMR study. Structures and chemical shifts for thirteen new compounds were assigned, and the identity of three known compounds was confirmed.
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Affiliation(s)
- Katarzyna Bus
- National Medicines Institute, Department of Spectrometric Methods, 30/34 Chełmska, 00-725 Warsaw, Poland
| | - Jerzy Sitkowski
- National Medicines Institute, Counterfeit Medicinal Products and Designer Drugs Department, 30/34 Chełmska, 00-725 Warsaw, Poland
| | - Wojciech Bocian
- National Medicines Institute, Counterfeit Medicinal Products and Designer Drugs Department, 30/34 Chełmska, 00-725 Warsaw, Poland
| | - Adam Zmysłowski
- National Medicines Institute, Department of Spectrometric Methods, 30/34 Chełmska, 00-725 Warsaw, Poland
| | - Karol Ofiara
- National Medicines Institute, Department of Spectrometric Methods, 30/34 Chełmska, 00-725 Warsaw, Poland
| | - Arkadiusz Szterk
- Center for Translationale Medicine Warsaw University for Life Sciences, Nowoursynowska 100, 02-797 Warsaw, Poland; Instytut Innowacji Przemysłowych MAT, 3/63 Rabindranatha Tagore, 02-647 Warsaw, Poland. %
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Simultaneous Determination of Vitamins D3 (Calcitriol, Cholecalciferol) and K2 (Menaquinone-4 and Menaquinone-7) in Dietary Supplements by UHPLC. Molecules 2021; 26:molecules26226982. [PMID: 34834074 PMCID: PMC8624398 DOI: 10.3390/molecules26226982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/13/2021] [Accepted: 11/17/2021] [Indexed: 11/16/2022] Open
Abstract
The content and composition of dietary supplements is of great interest due to their increasing consumption and variety of available brand offered in the market. Accurate determination of vitamins is important for the improvement of dietary supplement quality and nutrition assessments. In this regard, the simultaneous determination of vitamin D3 (calcitriol-CT and cholecalciferol-CHL) and K2 (menaquinone-4-MK-4 and menaquinone-7-MK-7) in dietary supplements was developed by using ultra-high-pressure liquid chromatography (UHPLC). The overall runtime per sample was above 35 min, with the retention times of 2.40, 6.59, 7.06, and 32.6 min for vitamin D3 (CT and CHL) and vitamin K2 (MK-4 and MK-7), respectively. The limits of detection and limits of quantification for the target nutritional compounds ranged between 0.04-0.05 µg/mL, respectively. The validation results indicated that the method had reasonable linearity (R2 ≥ 0.9990), good recovery (>82%), satisfactory intra-day precision (≤1.9%) and inter-day precision (≤3.5%), and high selectivity and specificity. The validated UHPLC method was demonstrated to be precise, accurate, and robust for the simultaneous determination of vitamins D3 (CT and CHL) and K2 (MK-4 and MK-7) in dietary supplements.
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Cis and trans isomers of the vitamin menaquinone-7: which one is biologically significant? Appl Microbiol Biotechnol 2020; 104:2765-2776. [PMID: 32009201 DOI: 10.1007/s00253-020-10409-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 01/15/2020] [Accepted: 01/23/2020] [Indexed: 12/20/2022]
Abstract
Recently, several studies have indicated that an adequate intake of menaquinone-7 (MK-7) offers numerous health benefits. However, the low availability of MK-7 in the diet necessitates the development of dietary supplements or functional food products to complement natural food sources and meet the daily intake requirements. Like most biological molecules, MK-7 can exist as geometric isomers that can occur in the cis, trans, and cis/trans forms; however, only the all-trans form is biologically significant. MK-7 is traditionally produced through bacterial fermentation, but various synthetic preparations have lately become available. The isomer composition in the final product is influenced by numerous factors, including the methods of production and purification, as well as particular environmental and storage conditions. The MK-7 profile obtained from the various production methods has not yet been elucidated, and the ideal method for the synthesis of the all-trans form of the vitamin is also debatable. Consequently, the quantification of the MK-7 profile of various products is necessary to develop an understanding of the factors that influence the proportion of isomers that are obtained in different preparations. Several possible methods exist for the quantification of MK-7 isomers, and of these, liquid chromatography in conjunction with mass spectrometry techniques appears to be the most promising. Evaluation of the isomer composition is an important consideration, as only the all-trans form sustains biological activity. Furthermore, knowledge of the prominent factors that influence the MK-7 composition may also enable their manipulation to obtain a more favorable MK-7 profile in the final product.
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UPLC-MS/MS determination of steroid hormones via a novel reaction based on derivatisation by a cyclic-organophosphate. Talanta 2019; 204:415-423. [PMID: 31357314 DOI: 10.1016/j.talanta.2019.06.046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/07/2019] [Accepted: 06/10/2019] [Indexed: 11/24/2022]
Abstract
A cyclic-organophosphate, specifically 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane-2-oxide, was used to derivatise the hydroxyl group at the C3 position of selected steroid hormones to analyse the derivatives using UPLC-MS/MS (ultra-performance liquid chromatography-tandem mass spectrometry). Reactions were performed in an anhydrous pyridine environment in the presence of AlCl3 at 50 °C. The developed reaction is suitable for analytical chemistry applications and was validated by analysis of selected contraceptive drugs. The sensitivity of the method depends on hormone tested and the limit of detection ranges from 130 pg/mL for β-estradiol to 240 pg/mL for estriol. The estimated efficiency of derivatisation reactions varies in the range from 77.5 to 95.7%, and depends upon the hormone undergoing derivatisation. The method's recovery rate for the lowest concentration tested (800 pg/mL) is 88.1-96.3%. The method exhibits linearity in the 390 pg/mL to 2.5 μg/mL range, with R2 = 0.997. The developed steroid hormone derivatisation reaction was validated experimentally using UHPLC-QTOF-MS (ultra-high performance liquid chromatography quadrupole time of flight mass spectrometry) and NMR (nuclear magnetic resonance) spectroscopy. These studies show that the developed derivatisation reaction provides a precise and repeatable determination of selected steroid hormones in contraceptive drugs. At n = 10, CV (Coefficient of Variation) did not exceed 7%, which is a very good result compared with other analytical methods.
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Wu C, Wang L, Li H, Yu S. Determination of 4(5)-methylimidazole in foods and beverages by modified QuEChERS extraction and liquid chromatography-tandem mass spectrometry analysis. Food Chem 2018; 280:278-285. [PMID: 30642498 DOI: 10.1016/j.foodchem.2018.12.065] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 11/14/2018] [Accepted: 12/13/2018] [Indexed: 10/27/2022]
Abstract
The determination of carcinogenic 4(5)-methylimidazole (4-MeI) in complex matrices at trace levels is a challenge because of its higher polarity and weaker column retention capability. Here, we proposed a novel method for the quantification of 4-MeI in various foods and beverages using modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The evaluated QuEChERS extraction with LC-MS/MS method showed excellent linearity (1-200 μg/L, with correlation coefficient (R2) > 0.999), trueness (91-113%), and precision (relative standard deviation (RSD) ≤ 12.3%), but low matrix effect (92-108%) for cola, tea, beer, coffee beverage, bread, biscuit and instant coffee. The expanded measurement uncertainty was less than 34.4% at 95% confidence level. The proposed method can be successfully applied to determine 4-MeI in 28 commercial foods and beverages purchased from local market. Therefore, we believe this method is likely to provide a potential for 4-MeI determination in practical application.
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Affiliation(s)
- Chunjian Wu
- College of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China; Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou 510640, China
| | - Li Wang
- Guangzhou Quality Supervision and Testing Institute, Guangzhou 511447, China
| | - He Li
- College of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China; Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou 510640, China
| | - Shujuan Yu
- College of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China; Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou 510640, China.
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