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Liang D, Dirndorfer S, Somoza V, Krautwurst D, Lang R, Hofmann T. Metabolites of Key Flavor Compound 2,3,5-Trimethylpyrazine in Human Urine. J Agric Food Chem 2022; 70:15134-15142. [PMID: 36399543 PMCID: PMC9733599 DOI: 10.1021/acs.jafc.2c06418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/26/2022] [Accepted: 10/26/2022] [Indexed: 06/16/2023]
Abstract
Pyrazines are among the most important compound class conveying the odor impressions "roasty", "nutty", and "earthy". They are formed by the Maillard reaction and occur ubiquitously in heated foods. The excretion of metabolites of the key flavor odorant 2,3,5-trimethylpyrazine, abundant in the volatile fraction of roasted coffee, was investigated. Based on literature suggestions, putative phase 1 and phase 2 metabolites were synthesized, characterized by nuclear magnetic resonance and mass spectroscopy data and used as standards for targeted, quantitative analysis of coffee drinkers' urine using stable-isotope-dilution-ultrahigh-performance liquid chromatography tandem mass spectroscopy (SIDA-UHPLC-MS/MS). The analysis of spot urine samples from a coffee intervention study revealed 3,6-dimethylpyrazine-2-carboxylic acid, 3,5-dimethylpyrazine-2-carboxylic acid, and 5,6-dimethylpyrazine-2-carboxylic acid were quantitatively dominating metabolites. Only negligible traces of pyrazinemethanols (3,6-dimethyl-2-pyrazinemethanol and 3,5,6-trimethylpyrazine-2-ol), glucuronides ((3,6-dimethylpyrazine-2-yl-)methyl-O-β-D-glucuronide and (3,5-dimethylpyrazine-2-yl-)methyl-O-β-D-glucuronide), and sulfates ((3,6-dimethylpyrazine-2-yl-)methyl-sulfate and (3,5-dimethylpyrazine-2-yl-)methyl-sulfate) were detected.
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Affiliation(s)
- Dong Liang
- Leibniz
Institute for Food Systems Biology at the Technical University Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany
- Chair
for Food Chemistry and Molecular Sensory Science, Technical University Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany
| | - Sebastian Dirndorfer
- Leibniz
Institute for Food Systems Biology at the Technical University Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany
| | - Veronika Somoza
- Leibniz
Institute for Food Systems Biology at the Technical University Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany
| | - Dietmar Krautwurst
- Leibniz
Institute for Food Systems Biology at the Technical University Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany
| | - Roman Lang
- Leibniz
Institute for Food Systems Biology at the Technical University Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany
| | - Thomas Hofmann
- Leibniz
Institute for Food Systems Biology at the Technical University Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany
- Chair
for Food Chemistry and Molecular Sensory Science, Technical University Munich, Lise-Meitner-Str. 34, 85354 Freising, Germany
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Lang R, Beusch A, Dirndorfer S. Metabolites of dietary atractyligenin glucoside in coffee drinkers' urine. Food Chem 2022; 405:135026. [DOI: 10.1016/j.foodchem.2022.135026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 11/17/2022] [Accepted: 11/19/2022] [Indexed: 11/25/2022]
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Tahanzadeh N, Knop M, Seidler Y, Dirndorfer S, Lürsen K, Bruchhaus I, Lang R, Rimbach G, Roeder T. An aqueous extract of the brown alga Eisenia bicyclis extends lifespan in a sex-specific manner by interfering with the Tor-FoxO axis. Aging (Albany NY) 2022; 14:6427-6448. [PMID: 35980274 PMCID: PMC9467403 DOI: 10.18632/aging.204218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 07/21/2022] [Indexed: 01/24/2023]
Abstract
Food has a decisive influence on our health, to the extent where even lifespan can be directly affected by it. In the present work, we have examined the effects of an aqueous extract of the marine brown alga Eisenia bicyclis in terms of its potential to extend lifespan. For this purpose, we used the fruit fly Drosophila melanogaster as a model. The experiments showed that small amounts of Eisenia extract can extend lifespan by up to 40%. This effect is not only related to the median but also to the maximum lifespan. Interestingly, this life-extending effect is sex-specific, i.e. it occurs exclusively in females. Even under stressful nutritional conditions such as a high sugar diet, this effect is detectable. Mechanistic studies showed that this life-prolonging effect depends on a functional Tor and a functional FoxO signaling pathway. It can be concluded that components of the Eisenia extract prolong lifespan by interacting with the Tor-FoxO axis. This study may serve to stimulate further investigations, which on the one hand show such a life-prolonging effect also in other organisms and on the other hand identify the substances responsible for this effect. Finally, it may also encourage the increased use of arame as a health-promoting food supplement.
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Affiliation(s)
- Navid Tahanzadeh
- Kiel University, Department Molecular Physiology, Zoology, Kiel, Germany
| | - Mirjam Knop
- Kiel University, Department Molecular Physiology, Zoology, Kiel, Germany
| | - Yvonne Seidler
- Kiel University, Institute of Human Nutrition and Food Science, Kiel, Germany
| | | | - Kai Lürsen
- Kiel University, Institute of Human Nutrition and Food Science, Kiel, Germany
| | - Iris Bruchhaus
- Bernhard-Nocht-Institute for Tropical Medicine, Department Parasitology, Hamburg, Germany
| | - Roman Lang
- Leibniz Institute for Food Systems Biology, TU Munich, Munich, Germany
| | - Gerald Rimbach
- Kiel University, Institute of Human Nutrition and Food Science, Kiel, Germany
| | - Thomas Roeder
- Kiel University, Department Molecular Physiology, Zoology, Kiel, Germany
- DZL, German Center for Lung Research, ARCN, Airway Research Center North, Kiel, Germany
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Brandl B, Rennekamp R, Reitmeier S, Pietrynik K, Dirndorfer S, Haller D, Hofmann T, Skurk T, Hauner H. Offering Fiber-Enriched Foods Increases Fiber Intake in Adults With or Without Cardiometabolic Risk: A Randomized Controlled Trial. Front Nutr 2022; 9:816299. [PMID: 35252300 PMCID: PMC8890034 DOI: 10.3389/fnut.2022.816299] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 01/17/2022] [Indexed: 12/18/2022] Open
Abstract
Introduction Previous efforts to increase fiber intake in the general population were disappointing despite growing awareness of the multiple benefits of a high fiber intake. Aim of the study was to investigate the acceptance and consumption of fiber-enriched foods. Methods One hundred and fifteen middle-aged healthy individuals with and without elevated waist circumference (> 102 cm in males and > 88 cm in females) were recruited and randomized to an intervention or an age- and sex-matched control group. Subjects assigned to the intervention group were invited to select fiber-enriched foods from a broad portfolio of products to increase fiber intake by 10 g/day. Control subjects could choose items from the same food basket without fiber enrichment. The primary outcome was the increase in dietary fiber intake, and secondary outcomes were changes in cardiometabolic risk factors, microbiota composition, food choices, and consumer acceptance of the fiber-enriched foods. Results Compared to baseline, daily fiber intake increased from 22.5 ± 8.0 to 34.0 ± 9.6 g/day after 4 weeks (p < 0.001) and to 36.0 ± 8.9 g/day after 12 weeks (p < 0.001) in the intervention group, whereas fiber intake remained unchanged in the control group. Participants rated the taste of the food products as pleasant without group differences. In both groups, the most liked foods included popular convenience foods such as pretzel breadstick, pizza salami, and pizza vegetarian. After 12 weeks of intervention, there were minor improvements in plasma lipids and parameters of glucose metabolism in both the intervention and control group compared to baseline, but no differences between the two groups. Increased fiber consumption resulted in an increased (p < 0.001) relative abundance of Tannerellaceae. Conclusions Fiber-enrichment of popular foods increases fiber intake in a middle-aged population with and without cardiometabolic risk and may provide a simple, novel strategy to increase fiber intake in the population.
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Affiliation(s)
- Beate Brandl
- ZIEL-Institute for Food and Health, Technical University of Munich, Freising, Germany
- Chair of Nutritional Medicine, Else Kroener-Fresenius-Centre for Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Rachel Rennekamp
- Chair of Nutritional Medicine, Else Kroener-Fresenius-Centre for Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Sandra Reitmeier
- ZIEL-Institute for Food and Health, Technical University of Munich, Freising, Germany
| | - Katarzyna Pietrynik
- Chair of Nutritional Medicine, Else Kroener-Fresenius-Centre for Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Sebastian Dirndorfer
- Chair of Food Chemistry and Molecular Sensory Science, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Dirk Haller
- ZIEL-Institute for Food and Health, Technical University of Munich, Freising, Germany
- Chair of Nutrition and Immunology, Technical University of Munich, Freising, Germany
| | - Thomas Hofmann
- Chair of Food Chemistry and Molecular Sensory Science, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Thomas Skurk
- ZIEL-Institute for Food and Health, Technical University of Munich, Freising, Germany
- Chair of Nutritional Medicine, Else Kroener-Fresenius-Centre for Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Hans Hauner
- Chair of Nutritional Medicine, Else Kroener-Fresenius-Centre for Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
- Institute of Nutritional Medicine, School of Medicine, Technical University of Munich, Munich, Germany
- *Correspondence: Hans Hauner
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Dirndorfer S, Hammerl R, Kitajima S, Kitada R, Frank O, Dunkel A, Hofmann T. Identification and Quantitation of Taste-Active Compounds in Dried Scallops by Combined Application of the Sensomics and a Quantitative NMR Approach. J Agric Food Chem 2022; 70:247-259. [PMID: 34965128 DOI: 10.1021/acs.jafc.1c05257] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Application of the sensomics concept on dried scallops, a Japanese specialty produced from the adductor muscle of scallops, revealed after activity-guided fractionation with subsequent (comparative) taste dilution analyses besides nucleotides, amino acids, organic acids, and inorganic ions, the presence of taste-modulating quaternary ammonium compounds and opines in highly taste-active fractions. In order to recreate the taste of dried scallops, two independent quantitation approaches were applied and compared. The first approach used multiple targeted UHPLC-MS/MS and high-performance ion chromatography methods. Besides already established quantitation methods for basic taste compounds, a new HILIC-UHPLC-MS/MSMRM method for the quantitation of chromatographically challenging opines, using synthesized stable isotope-labeled standards, was developed. Furthermore, a qHNMR approach was applied, enabling a direct identification and quantitation of organic taste compounds in a food extract without prior fractionation using a reference 1H NMR database. Both methods yielded similar quantitative results of taste-active compounds in dried scallop extracts and subsequent taste recombination experiments based on these data were able to recreate the taste of dried scallops.
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Affiliation(s)
- Sebastian Dirndorfer
- Chair of Food Chemistry and Molecular and Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, D-85354 Freising, Germany
| | - Richard Hammerl
- Chair of Food Chemistry and Molecular and Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, D-85354 Freising, Germany
| | - Seiji Kitajima
- Institute of Food Sciences & Technologies, Ajinomoto Co., Inc., 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki, Kanagawa 210-8681, Japan
| | - Ryo Kitada
- Institute of Food Sciences & Technologies, Ajinomoto Co., Inc., 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki, Kanagawa 210-8681, Japan
| | - Oliver Frank
- Chair of Food Chemistry and Molecular and Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, D-85354 Freising, Germany
| | - Andreas Dunkel
- Leibniz-Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, D-85354 Freising, Germany
| | - Thomas Hofmann
- Chair of Food Chemistry and Molecular and Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, D-85354 Freising, Germany
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N Diaye K, Debong M, Behr J, Dirndorfer S, Duggan T, Beusch A, Schlagbauer V, Dawid C, Loos HM, Buettner A, Lang R, Hofmann T. Dietary Piperine is Transferred into the Milk of Nursing Mothers. Mol Nutr Food Res 2021; 65:e2100508. [PMID: 34633734 DOI: 10.1002/mnfr.202100508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 09/08/2021] [Indexed: 11/11/2022]
Abstract
INTRODUCTION The diet of breastfeeding mothers could bring nurslings into contact with flavor compounds putatively contributing to early sensory programming of the infant. The study investigates whether tastants from a customary curry dish consumed by mothers are detectable in their milk afterwards and can be perceived by the infant. METHODS AND RESULTS Sensory evaluation identifies pungency as the dominating taste impression of the curry dish. Its ingredients of chili, pepper, and ginger suggest the flavor compounds capsaicin, piperine, and 6-gingerol as analytical targets. Breastfeeding mothers are recruited for an intervention trial involving the consumption of the curry dish and subsequent collection of milk samples for flavor compound analysis. Targeted and untargeted mass spectrometric (MS)- investigations identify exclusively piperine as an intervention-derived compound in human milk. However, concentrations are below the human taste threshold. CONCLUSION Piperine from pepper-containing foods transfers into the mother's milk within 1 h and is delivered to the nursling. Concentrations of 50 and 200 nM of piperine are 70-350 times below the human taste threshold, but TRPV1 (Transient Receptor Potential Vanilloid-1 ion channel) desensitization through frequent exposure to sub-taste-threshold concentrations could contribute to an increased tolerance at a later age.
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Affiliation(s)
- Katharina N Diaye
- Food Chemistry and Molecular Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, Freising, 85354, Germany
| | - Marcel Debong
- Aroma and Smell Research, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestr. 9, Erlangen, 91054, Germany
| | - Jürgen Behr
- Leibniz Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, Freising, 85354, Germany
| | - Sebastian Dirndorfer
- Leibniz Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, Freising, 85354, Germany
| | - Tara Duggan
- Food Chemistry and Molecular Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, Freising, 85354, Germany
| | - Anja Beusch
- Leibniz Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, Freising, 85354, Germany
| | - Verena Schlagbauer
- Food Chemistry and Molecular Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, Freising, 85354, Germany
| | - Corinna Dawid
- Food Chemistry and Molecular Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, Freising, 85354, Germany
| | - Helene M Loos
- Aroma and Smell Research, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestr. 9, Erlangen, 91054, Germany.,Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Str. 35, Freising, 85354, Germany
| | - Andrea Buettner
- Aroma and Smell Research, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestr. 9, Erlangen, 91054, Germany.,Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Str. 35, Freising, 85354, Germany
| | - Roman Lang
- Food Chemistry and Molecular Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, Freising, 85354, Germany.,Leibniz Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, Freising, 85354, Germany
| | - Thomas Hofmann
- Food Chemistry and Molecular Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, Freising, 85354, Germany
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Rebholz GF, Sebald K, Dirndorfer S, Dawid C, Hofmann T, Scherf KA. Impact of exogenous maltogenic α-amylase and maltotetraogenic amylase on sugar release in wheat bread. Eur Food Res Technol 2021. [DOI: 10.1007/s00217-021-03721-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AbstractThe use of exogenous maltogenic α-amylases or maltotetraogenic amylases of bacterial origin is common in wheat bread production, mainly as antistaling agents to retard crumb firming. To study the impact of maltogenic α-amylase and maltotetraogenic amylase on straight dough wheat bread, we performed a discovery-driven proteomics approach with commercial enzyme preparations and identified the maltotetraogenic amylase P22963 from Pelomonas saccharophila and the maltogenic α-amylase P19531 from Geobacillus stearothermophilus, respectively, as being responsible for the amylolytic activity. Quantitation of mono-, di- and oligosaccharides and residual amylase activity in bread crumb during storage for up to 96 h clarified the different effects of residual amylase activity on the sugar composition. Compared to the control, the application of maltogenic α-amylase led to an increased content of maltose and especially higher maltooligosaccharides during storage. Residual amylase activity was detectable in the breads containing maltogenic α-amylase, whereas maltotetraogenic amylase only had a very low residual activity. Despite the residual amylase activities and changes in sugar composition detected in bread crumb, our results do not allow a definite evaluation of a potential technological function in the final product. Rather, our study contributes to a fundamental understanding of the relation between the specific amylases applied, their residual activity and the resulting changes in the saccharide composition of wheat bread during storage.
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Rebholz GF, Sebald K, Dirndorfer S, Dawid C, Hofmann T, Scherf KA. Impact of exogenous α-amylases on sugar formation in straight dough wheat bread. Eur Food Res Technol 2020. [DOI: 10.1007/s00217-020-03657-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AbstractThe use of bacterial or fungal α-amylases is common in wheat bread production to improve several quality-related parameters such as loaf volume, crust color or staling behavior. To study the impact of exogenous α-amylases on straight dough wheat bread, we quantitated mono-, di- and oligosaccharides and residual α-amylase activity in bread crumb during storage for up to 96 h. Discovery-driven proteomics of the five α-amylase preparations studied showed that only a few different amylases per preparation were responsible for the hydrolytic effect. Compared to the control, the supplementation with α-amylase from Bacillus amyloliquefaciens in wheat dough preparation led to major changes in the sugar composition of bread crumb during storage with the formation of oligosaccharides like maltopentaose, maltohexaose, maltoheptaose, and maltooctaose. A residual activity corresponding to 4.0% of the applied activity was determined in the breads prepared with α-amylase from B. amyloliquefaciens, but no residual activity was detected for any of the other fungal or bacterial α-amylases from Aspergillus oryzae or Thermoactinomyces vulgaris. Whether the detected residual activity is related to the characteristics of bread staling or bread crumb properties must be clarified in further studies.
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Phewpan A, Phuwaprisirisan P, Takahashi H, Ohshima C, Ngamchuachit P, Techaruvichit P, Dirndorfer S, Dawid C, Hofmann T, Keeratipibul S. Investigation of Kokumi Substances and Bacteria in Thai Fermented Freshwater Fish (Pla-ra). J Agric Food Chem 2020; 68:10345-10351. [PMID: 31757121 DOI: 10.1021/acs.jafc.9b06107] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A 16S rRNA next-generation sequencing technique was applied to investigate the microbial diversity and liquid chromatography-tandem mass spectrometry was used to identify glutamyl peptide profiles of 10 Thai fermented freshwater fish (Pla-ra) samples. A total of 12 genera of bacteria were able to be detected, with Tetragenococcus spp., Staphylococcus spp., and Lactobacillus spp. dominating. Of the 18 glutamyl peptides analyzed, 17 were found, even though the amounts detected were lower than the taste threshold. Despite this, an increase in mouthfulness sensation, reflecting kokumi activity, was clearly identified in most of the samples, which might be because of a synergistic effect of different sub-threshold compounds present in the samples. In principle component analysis, the relationship between microorganisms and glutamyl peptide generation was observed, especially between Tetragenococcus spp. and Lentibacillus spp. and the generation of γ-Glu-Val-Gly. Correlations between microbial diversity and the generation of taste enhancers were identified in this study.
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Affiliation(s)
| | | | - Hajime Takahashi
- Department of Food Science and Technology, Tokyo University of Marine Science and Technology, Tokyo 108-8477, Japan
| | - Chihiro Ohshima
- Department of Food Science and Technology, Tokyo University of Marine Science and Technology, Tokyo 108-8477, Japan
| | | | - Punnida Techaruvichit
- Research and Development Center, Betagro Group, Klong Luang, Pathum Thani 10120, Thailand
| | - Sebastian Dirndorfer
- Chair of Food Chemistry and Molecular and Sensory Science, Technische Universität München, Lise-Meitner-Straße 34, D-84354 Freising, Germany
| | - Corinna Dawid
- Chair of Food Chemistry and Molecular and Sensory Science, Technische Universität München, Lise-Meitner-Straße 34, D-84354 Freising, Germany
| | - Thomas Hofmann
- Chair of Food Chemistry and Molecular and Sensory Science, Technische Universität München, Lise-Meitner-Straße 34, D-84354 Freising, Germany
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Melnik S, Neumann AC, Karongo R, Dirndorfer S, Stübler M, Ibl V, Niessner R, Knopp D, Stoger E. Cloning and plant-based production of antibody MC10E7 for a lateral flow immunoassay to detect [4-arginine]microcystin in freshwater. Plant Biotechnol J 2018; 16:27-38. [PMID: 28421663 PMCID: PMC5785354 DOI: 10.1111/pbi.12746] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 03/14/2017] [Accepted: 04/12/2017] [Indexed: 06/07/2023]
Abstract
Antibody MC10E7 is one of a small number of monoclonal antibodies that bind specifically to [Arg4]-microcystins, and it can be used to survey natural water sources and food samples for algal toxin contamination. However, the development of sensitive immunoassays in different test formats, particularly user-friendly tests for on-site analysis, requires a sensitive but also cost-effective antibody. The original version of MC10E7 was derived from a murine hybridoma, but we determined the sequence of the variable regions using the peptide mass-assisted cloning strategy and expressed a scFv (single-chain variable fragment) format of this antibody in yeast and a chimeric full-size version in leaves of Nicotiana tabacum and Nicotiana benthamiana to facilitate inexpensive and scalable production. The specific antigen-binding activity of the purified antibody was verified by surface plasmon resonance spectroscopy and ELISA, confirming the same binding specificity as its hybridoma-derived counterpart. The plant-derived antibody was used to design a lateral flow immunoassay (dipstick) for the sensitive detection of [Arg4]-microcystins at concentrations of 100-300 ng/L in freshwater samples collected at different sites. Plant-based production will likely reduce the cost of the antibody, currently the most expensive component of the dipstick immunoassay, and will allow the development of further antibody-based analytical devices and water purification adsorbents for the efficient removal of toxic contaminants.
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Affiliation(s)
- Stanislav Melnik
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Anna-Cathrine Neumann
- Institute of Hydrochemistry and Chair for Analytical Chemistry, Technical University Munich, Munich, Germany
| | - Ryan Karongo
- Institute of Hydrochemistry and Chair for Analytical Chemistry, Technical University Munich, Munich, Germany
| | - Sebastian Dirndorfer
- Institute of Hydrochemistry and Chair for Analytical Chemistry, Technical University Munich, Munich, Germany
| | - Martin Stübler
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Verena Ibl
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Reinhard Niessner
- Institute of Hydrochemistry and Chair for Analytical Chemistry, Technical University Munich, Munich, Germany
| | - Dietmar Knopp
- Institute of Hydrochemistry and Chair for Analytical Chemistry, Technical University Munich, Munich, Germany
| | - Eva Stoger
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
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Schmid W, Dirndorfer S, Juranowitsch H, Kress M, Petry W. Adhesion strength of sputter deposited diffusion barrier layer coatings for the use in U–Mo nuclear fuels. Nuclear Engineering and Design 2014. [DOI: 10.1016/j.nucengdes.2014.05.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
Abstract
A condensation induced water hammer is a severe effect that has caused damages and even fatalities worldwide. This effect is not limited to the nuclear industry only. Generally it can occur in every pipe that contains water and steam (two-phase-flow). To date many experiments were executed to study this phenomenon and to validate existing water hammer codes. But theoretically versus measured results show a very high degree of deviation. Information about those experiments was obtained by literature review. This information is presented additionally to a test facility, which has been developed in order to generate water hammers. The test device is introduced in this paper and its main functions are briefly explained.
In contrast to other experiments, water hammers at the UniBw are performed under controlled conditions. Air in water is a disruptive parameter that causes vigorous deviations between the theoretical system code and the experimental measurements. As in the test device presented in this paper, deionised water without air is used, this effect is ruled out. Furthermore the inception of a water hammer is controlled by a scientist. The experimental results will characterise the dynamic response of the test device as a function of system pressure, filling degree and sub-cooling.
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Affiliation(s)
| | | | | | - A. Malcherek
- Universität der Bundeswehr München (UniBw), Institute of Hydromechanics and Hydraulic Engineering, Werner-Heisenberg-Weg 39, D-85577 Neubiberg, Germany. E-mail:
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Abstract
Abstract
Condensation-induced water hammers belong to the most serious and complex pressure surges. Experimental data from literature are scanty, incomplete, not public or simply missing. A new test facility at the UniBw (University of the German Armed Forces) was constructed to perform own experiments within a research alliance. This new test facility uses a complete new approach. In contrast to other test stations, the UniBw water hammer test facility is a closed system. This leads on the one hand to a more complex handling with respect of conducting experiments but on the other hand also to a more realistic characterization of thermo-hydraulic phenomena which can occur in a power plant. The first results of a measured condensation-induced water hammer are presented.
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Affiliation(s)
- S. Dirndorfer
- Universität der Bundeswehr München, Hydromechanik und Wasserbau, Institut für Wasserwesen, Werner-Heisenberg-Weg 39, 85577 Neubiberg
| | - H. Kulisch
- Dr.-Ing. Helmut Kulisch, E-mail:
- Universität der Bundeswehr München, Hydromechanik und Wasserbau, Institut für Wasserwesen, Werner-Heisenberg-Weg 39, 85577 Neubiberg
| | - A. Malcherek
- Prof.-Dr.-Ing. Andreas Malcherek, E-mail:
- Universität der Bundeswehr München, Hydromechanik und Wasserbau, Institut für Wasserwesen, Werner-Heisenberg-Weg 39, 85577 Neubiberg
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