1
|
Schaper G, Wenzel M, Schwarzenbolz U, Steup J, Hennersdorf F, Henle T, Lindoy LF, Weigand JJ. Insights at the molecular level into the formation of oxo-bridged trinuclear uranyl complexes. Chem Commun (Camb) 2022; 58:1748-1751. [PMID: 35029269 DOI: 10.1039/d1cc06310c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reaction of 1,3,4,6-tetra-O-acetyl-N-(2-hydroxy)-naphthylidene glucosamine (HL(Ac)) with uranyl acetate in ethanol leads to formation of dinuclear [(UO2)2(L)2] (1). In a second step 1 is quantitatively transferred into the trinuclear oxo-bridged complex [(UO2)3(μ3-O)(L)3]2- (22-) via deprotonation and coordination of a water molecule. This transformation was followed by NMR and UV/Vis spectroscopy and it proved possible to selectively introduce 18O into the μ3-bridge.
Collapse
Affiliation(s)
- Gerrit Schaper
- Chair of Inorganic Molecular Chemistry, Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany.
| | - Marco Wenzel
- Chair of Inorganic Molecular Chemistry, Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany.
| | - Uwe Schwarzenbolz
- Chair of Food Chemistry, Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
| | - Johannes Steup
- Chair of Inorganic Molecular Chemistry, Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany.
| | - Felix Hennersdorf
- Chair of Inorganic Molecular Chemistry, Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany.
| | - Thomas Henle
- Chair of Food Chemistry, Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
| | - Leonard F Lindoy
- School of Chemistry, F11, University of Sydney, NSW 2006 Sydney, Australia
| | - Jan J Weigand
- Chair of Inorganic Molecular Chemistry, Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany.
| |
Collapse
|
2
|
Aganovic K, Hertel C, Vogel RF, Johne R, Schlüter O, Schwarzenbolz U, Jäger H, Holzhauser T, Bergmair J, Roth A, Sevenich R, Bandick N, Kulling SE, Knorr D, Engel KH, Heinz V. Aspects of high hydrostatic pressure food processing: Perspectives on technology and food safety. Compr Rev Food Sci Food Saf 2021; 20:3225-3266. [PMID: 34056857 DOI: 10.1111/1541-4337.12763] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [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: 07/31/2020] [Revised: 04/02/2021] [Accepted: 04/10/2021] [Indexed: 11/29/2022]
Abstract
The last two decades saw a steady increase of high hydrostatic pressure (HHP) used for treatment of foods. Although the science of biomaterials exposed to high pressure started more than a century ago, there still seem to be a number of unanswered questions regarding safety of foods processed using HHP. This review gives an overview on historical development and fundamental aspects of HHP, as well as on potential risks associated with HHP food applications based on available literature. Beside the combination of pressure and temperature, as major factors impacting inactivation of vegetative bacterial cells, bacterial endospores, viruses, and parasites, factors, such as food matrix, water content, presence of dissolved substances, and pH value, also have significant influence on their inactivation by pressure. As a result, pressure treatment of foods should be considered for specific food groups and in accordance with their specific chemical and physical properties. The pressure necessary for inactivation of viruses is in many instances slightly lower than that for vegetative bacterial cells; however, data for food relevant human virus types are missing due to the lack of methods for determining their infectivity. Parasites can be inactivated by comparatively lower pressure than vegetative bacterial cells. The degrees to which chemical reactions progress under pressure treatments are different to those of conventional thermal processes, for example, HHP leads to lower amounts of acrylamide and furan. Additionally, the formation of new unknown or unexpected substances has not yet been observed. To date, no safety-relevant chemical changes have been described for foods treated by HHP. Based on existing sensitization to non-HHP-treated food, the allergenic potential of HHP-treated food is more likely to be equivalent to untreated food. Initial findings on changes in packaging materials under HHP have not yet been adequately supported by scientific data.
Collapse
Affiliation(s)
- Kemal Aganovic
- DIL German Institute of Food Technologies e.V., Quakenbrück, Germany
| | - Christian Hertel
- DIL German Institute of Food Technologies e.V., Quakenbrück, Germany
| | - Rudi F Vogel
- Technical University of Munich (TUM), Munich, Germany
| | - Reimar Johne
- German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Oliver Schlüter
- Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB), Potsdam, Germany.,Alma Mater Studiorum, University of Bologna, Cesena, Italy
| | | | - Henry Jäger
- University of Natural Resources and Life Sciences (BOKU), Wien, Austria
| | - Thomas Holzhauser
- Division of Allergology, Paul-Ehrlich-Institut (PEI), Langen, Germany
| | | | - Angelika Roth
- Senate Commission on Food Safety (DFG), IfADo, Dortmund, Germany
| | - Robert Sevenich
- Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB), Potsdam, Germany.,Technical University of Berlin (TUB), Berlin, Germany
| | - Niels Bandick
- German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | | | | | | | - Volker Heinz
- DIL German Institute of Food Technologies e.V., Quakenbrück, Germany
| |
Collapse
|
3
|
Neukam PT, Deza-Araujo YI, Marxen M, Pooseh S, Rietschel M, Schwarzenbolz U, Smolka MN. No evidence for the involvement of serotonin or the 5-HTTLPR genotype in intertemporal choice in a larger community sample. J Psychopharmacol 2019; 33:1377-1387. [PMID: 31547761 DOI: 10.1177/0269881119874417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Serotonin has been implicated in impulsive behaviours such as temporal discounting. While animal studies and theoretical approaches suggest that reduced tonic serotonin levels increase temporal discounting rates and vice versa, evidence from human studies is scarce and inconclusive. Furthermore, an important modulator of serotonin signalling, a genetic variation in the promoter region of the serotonin transporter gene (5-HTTLPR), has not been investigated for temporal discounting so far. OBJECTIVE First, the purpose of this study was to test for a significant association between 5-HTTLPR and temporal discounting. Second, we wished to investigate the effect of high/low tonic serotonin levels on intertemporal choice and blood oxygen-level-dependent response, controlling for 5-HTTLPR. METHODS We tested the association of 5-HTTLPR with temporal discounting rates using an intertemporal choice task in 611 individuals. We then manipulated tonic serotonin levels with acute tryptophan interventions (depletion, loading, balanced) in a subsample of 45 short (S)-allele and 45 long (L)/L-allele carriers in a randomised double-blind crossover design using functional magnetic resonance imaging and an intertemporal choice task. RESULTS Overall, we did not find any effect of serotonin and 5-HTTLPR on temporal discounting rates or the brain networks associated with valuation and cognitive control. CONCLUSION Our findings indicate that serotonin may not be directly involved in choices including delays on longer timescales such as days, weeks or months. We speculate that serotonin plays a stronger role in dynamic intertemporal choice tasks where the delays are on a timescale of seconds and hence are therefore directly experienced during the experiment.
Collapse
Affiliation(s)
- Philipp T Neukam
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Yacila I Deza-Araujo
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Michael Marxen
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Shakoor Pooseh
- Freiburg Center for Data Analysis and Modeling, Freiburg, Germany
| | - Marcella Rietschel
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, University of Heidelberg, Mannheim, Germany
| | - Uwe Schwarzenbolz
- Institute of Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Michael N Smolka
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| |
Collapse
|
4
|
Hoefle AS, Bangert AM, Rist MJ, Gedrich K, Lee YM, Skurk T, Danier J, Schwarzenbolz U, Daniel H. Postprandial metabolic responses to ingestion of bovine glycomacropeptide compared to a whey protein isolate in prediabetic volunteers. Eur J Nutr 2018; 58:2067-2077. [PMID: 30003332 DOI: 10.1007/s00394-018-1763-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [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: 09/14/2017] [Accepted: 06/26/2018] [Indexed: 01/28/2023]
Abstract
PURPOSE Whey protein was shown to reduce blood glucose responses in humans and various other positive effects have been attributed to this protein. In contrast, studies using glycomacropeptide (GMP) as part of the whey fraction of bovine milk are rare. We, therefore, studied the postprandial responses to GMP administration in humans with impaired glucose tolerance compared to the effects of pure whey protein in a random design. METHODS Fifteen prediabetic volunteers received on different occasions one of three test drinks containing 50 g of maltodextrin19 (MD19) alone or in combination with either 50 g GMP or 50 g whey protein isolate (WPI). Blood was collected over 4 h with analysis of blood glucose and hormones, gastric emptying rate as well as plasma amino- and fatty acids, β-hydroxybutyrate and acylcarnitines. RESULTS The WPI drink reduced the AUC of venous blood glucose compared to the MD19 drink in the prediabetic group by 11% (p = 0.0018) whereas GMP reduced the AUC by 18% (p < 0.0001), significantly different to the WPI drink (p = 0.0384). The reduction in blood glucose after the GMP drink was accompanied by a significantly lower AUC of insulin (- 34%) than for the WPI drink. Levels of C-peptide and of glucose insulinotropic polypeptide (GIP) were highly increased after the WPI drink over the MD19 control drink but remained in essence unaffected by the GMP. CONCLUSION GMP reduced the glycemic response more potently than whey protein, whereas insulin output was less affected making GMP an interesting protein to control postprandial glucose responses.
Collapse
Affiliation(s)
- Anja S Hoefle
- Nutritional Physiology, Technical University of Munich, Gregor-Mendel-Str. 2, 85354, Freising, Germany
| | - Adina M Bangert
- Nutritional Physiology, Technical University of Munich, Gregor-Mendel-Str. 2, 85354, Freising, Germany
| | - Manuela J Rist
- Nutritional Physiology, Technical University of Munich, Gregor-Mendel-Str. 2, 85354, Freising, Germany.,Max Rubner-Institut, Haid-und-Neu-Str. 9, 76131, Karlsruhe, Germany
| | - Kurt Gedrich
- Nutritional Physiology, Technical University of Munich, Gregor-Mendel-Str. 2, 85354, Freising, Germany
| | - Yu-Mi Lee
- Nutritional Physiology, Technical University of Munich, Gregor-Mendel-Str. 2, 85354, Freising, Germany
| | - Thomas Skurk
- Else Kröner-Fresenius Center of Nutritional Medicine, Technical University of Munich, Gregor-Mendel-Str. 2, 85354, Freising, Germany.,Klinikum rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany
| | - Jürgen Danier
- Bioanalytik Weihenstephan, Technical University of Munich, Alte Akademie 10, 85354, Freising, Germany
| | - Uwe Schwarzenbolz
- Professur für Lebensmittelchemie, Technische Universität Dresden, Bergstr. 66, 01062, Dresden, Germany
| | - Hannelore Daniel
- Nutritional Physiology, Technical University of Munich, Gregor-Mendel-Str. 2, 85354, Freising, Germany.
| |
Collapse
|
5
|
Neukam PT, Kroemer NB, Deza Araujo YI, Hellrung L, Pooseh S, Rietschel M, Witt SH, Schwarzenbolz U, Henle T, Smolka MN. Risk-seeking for losses is associated with 5-HTTLPR, but not with transient changes in 5-HT levels. Psychopharmacology (Berl) 2018; 235:2151-2165. [PMID: 29730700 DOI: 10.1007/s00213-018-4913-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 04/17/2018] [Indexed: 10/17/2022]
Abstract
RATIONALE Serotonin (5-HT) plays a key role in different aspects of value-based decision-making. A recent framework proposed that tonic 5-HT (together with dopamine, DA) codes future average reward expectations, providing a baseline against which possible choice outcomes are compared to guide decision-making. OBJECTIVES To test whether high 5-HT levels decrease loss aversion, risk-seeking for gains, and risk-seeking for losses. METHODS In a first session, 611 participants were genotyped for 5-HTTLPR and performed a mixed gambles (MGA) task and two probability discounting tasks for gains and losses, respectively (PDG/PDL). Afterwards, a subsample of 105 participants (44 with S/S, 6 with S/L, 55 with L/L genotype) completed the pharmacological study using a crossover design with tryptophan depletion (ATD), loading (ATL), and balanced (BAL) conditions. The same decision constructs were assessed. RESULTS We found increased risk-seeking for losses in S/S compared to L/L individuals at the first visit (p = 0.002). Neither tryptophan depletion nor loading affected decision-making, nor did we observe an interaction between intervention and 5-HTTLPR genotype. CONCLUSION Our data do not support the idea that transient changes of tonic 5-HT affect value-based decision-making. We provide evidence for an association of 5-HTTLPR with risk-seeking for losses, independent of acute 5-HT levels. This indicates that the association of 5-HTTLPR and risk-seeking for losses is mediated via other mechanisms, possibly by differences in the structural development of neural circuits of the 5-HT system during early life phases.
Collapse
Affiliation(s)
- Philipp T Neukam
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Nils B Kroemer
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.,Department of Psychiatry and Psychotherapy, University of Tübingen, Tübingen, Germany
| | - Yacila I Deza Araujo
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Lydia Hellrung
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.,Department of Economics, University of Zürich, Zürich, Switzerland
| | - Shakoor Pooseh
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Marcella Rietschel
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Stephanie H Witt
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Uwe Schwarzenbolz
- Institute of Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Thomas Henle
- Institute of Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Michael N Smolka
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.
| |
Collapse
|
6
|
Schwarzenbolz U, Förster A, Henle T. Influence of high hydrostatic pressure on the reaction between glyoxal and lysine residues. Eur Food Res Technol 2017. [DOI: 10.1007/s00217-017-2846-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
7
|
Manig F, Kuhne K, von Neubeck C, Schwarzenbolz U, Yu Z, Kessler BM, Pietzsch J, Kunz-Schughart LA. The why and how of amino acid analytics in cancer diagnostics and therapy. J Biotechnol 2017; 242:30-54. [DOI: 10.1016/j.jbiotec.2016.12.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 11/28/2016] [Accepted: 12/01/2016] [Indexed: 12/11/2022]
|
8
|
Kelly N, Gloe K, Doert T, Hennersdorf F, Heine A, März J, Schwarzenbolz U, Weigand JJ, Gloe K. Self-assembly of [2+2] Co(II) metallomacrocycles and Ni(II) metallogels with novel bis(pyridylimine) ligands. J Organomet Chem 2016. [DOI: 10.1016/j.jorganchem.2016.04.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
9
|
Schwarzenbolz U, Hofmann T, Sparmann N, Henle T. Free Maillard Reaction Products in Milk Reflect Nutritional Intake of Glycated Proteins and Can Be Used to Distinguish "Organic" and "Conventionally" Produced Milk. J Agric Food Chem 2016; 64:5071-5078. [PMID: 27213835 DOI: 10.1021/acs.jafc.6b01375] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [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: 06/05/2023]
Abstract
Using LC-MS/MS and isotopically labeled standard substances, quantitation of free Maillard reaction products (MRPs), namely, N(ε)-(carboxymethyl)lysine (CML), 5-(hydroxymethyl)-1H-pyrrole-2-carbaldehyde (pyrraline, PYR), N(δ)-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H), and N(ε)-fructosyllysine (FL), in bovine milk was achieved. Considerable variations in the amounts of the individual MRPs were found, most likely as a consequence of the nutritional uptake of glycated proteins. When comparing commercial milk samples labeled as originating from "organic" or "conventional" farming, respectively, significant differences in the content of free PYR (organic milk, 20-300 pmol/mL; conventional milk, 400-1000 pmol/mL) were observed. An analysis of feed samples indicated that rapeseed and sugar beet are the main sources for MRPs in conventional farming. Furthermore, milk of different dairy animals (cow, buffalo, donkey, goat, ewe, mare, camel) as well as for the first time human milk was analyzed for free MRPs. The distribution of their concentrations, with FL and PYR as the most abundant in human milk and with a high individual variability, also points to a nutritional influence. As the components of concentrated feed do not belong to the natural food sources of ruminants and equidae, free MRPs in milk might serve as indicators for an adequate animal feeding in near-natural farming and can be suitable parameters to distinguish between an "organic" and "conventional" production method of milk.
Collapse
Affiliation(s)
- Uwe Schwarzenbolz
- Institute of Food Chemistry, Technische Universität Dresden , D-01062 Dresden, Germany
| | - Thomas Hofmann
- Institute of Food Chemistry, Technische Universität Dresden , D-01062 Dresden, Germany
| | - Nina Sparmann
- Institute of Food Chemistry, Technische Universität Dresden , D-01062 Dresden, Germany
| | - Thomas Henle
- Institute of Food Chemistry, Technische Universität Dresden , D-01062 Dresden, Germany
| |
Collapse
|
10
|
Rückriemen J, Schwarzenbolz U, Adam S, Henle T. Identification and Quantitation of 2-Acetyl-1-pyrroline in Manuka Honey (Leptospermum scoparium). J Agric Food Chem 2015; 63:8488-8492. [PMID: 26365614 DOI: 10.1021/acs.jafc.5b03042] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [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: 06/05/2023]
Abstract
Manuka honey from New Zealand is known for its exceptional antibacterial activity, which is due to high amounts of the 1,2-dicarbonyl compound methylglyoxal (MGO). MGO in manuka honey is formed via non-enzymatic dehydration from dihydroxyacetone (DHA) during honey maturation. MGO and DHA are highly reactive substances, leading to a variety of unique chemical reactions. During Strecker reaction between proline and MGO, 2-acetyl-1-pyrroline (2-AP), an important aroma compound, is formed. Using liquid-liquid extraction and gas chromatography-mass spectrometry analysis, 2-AP was identified unambiguously in manuka honey for the first time. Quantitation was carried out via external matrix calibration, using a synthetic 2-AP standard and artificial honey. The 2-AP concentration in 11 commercial samples of manuka honey ranged from 0.08 to 0.45 mg/kg. For manuka honey samples containing MGO in concentrations above 250 mg/kg, significantly higher amounts of 2-AP were found when compared to non-manuka honeys. When high amounts of MGO were artificially added to non-manuka multifloral honey, an increase of the 2-AP concentration from 0.07 to 0.40 mg/kg after 12 weeks of storage at 37 °C was observed, concomitant with a significant increase in the concentration of 5-hydroxymethylfurfural (HMF). No increase of 2-AP was found during storage at ambient temperature. 2-AP together with MGO can be a suitable parameter for the quality control of manuka honey.
Collapse
Affiliation(s)
- Jana Rückriemen
- Institute of Food Chemistry, Technische Universität Dresden , D-01062 Dresden, Germany
| | - Uwe Schwarzenbolz
- Institute of Food Chemistry, Technische Universität Dresden , D-01062 Dresden, Germany
| | - Simone Adam
- Institute of Food Chemistry, Technische Universität Dresden , D-01062 Dresden, Germany
| | - Thomas Henle
- Institute of Food Chemistry, Technische Universität Dresden , D-01062 Dresden, Germany
| |
Collapse
|
11
|
Jaros D, Schwarzenbolz U, Raak N, Löbner J, Henle T, Rohm H. Corrigendum to “Cross-linking with microbial transglutaminase: Relationship between polymerisation degree and stiffness of acid casein gels” [Int Dairy J 38 (2014) 174–178]. Int Dairy J 2014. [DOI: 10.1016/j.idairyj.2014.08.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
12
|
Jaros D, Schwarzenbolz U, Raak N, Löbner J, Henle T, Rohm H. Cross-linking with microbial transglutaminase: Relationship between polymerisation degree and stiffness of acid casein gels. Int Dairy J 2014. [DOI: 10.1016/j.idairyj.2013.10.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
13
|
|
14
|
Oboh G, Ademiluyi AO, Akinyemi AJ, Henle T, Saliu JA, Schwarzenbolz U. Inhibitory effect of polyphenol-rich extracts of jute leaf (Corchorus olitorius) on key enzyme linked to type 2 diabetes (α-amylase and α-glucosidase) and hypertension (angiotensin I converting) in vitro. J Funct Foods 2012. [DOI: 10.1016/j.jff.2012.02.003] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
|
15
|
Adebowale YA, Schwarzenbolz U, Henle T. Protein Isolates from Bambara Groundnut (Voandzeia SubterraneanL.): Chemical Characterization and Functional Properties. International Journal of Food Properties 2011. [DOI: 10.1080/10942910903420743] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
16
|
Schuh S, Schwarzenbolz U, Henle T. Cross-linking of hen egg white lysozyme by microbial transglutaminase under high hydrostatic pressure: localization of reactive amino acid side chains. J Agric Food Chem 2010; 58:12749-12752. [PMID: 21087031 DOI: 10.1021/jf103490w] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
After incubation of hen egg white lysozyme (HEWL) with microbial transglutaminase (mTG) under high pressure (400-600 MPa for 30 min at 40 °C), the formation of HEWL oligomers was observed via SDS electrophoresis. At atmospheric pressure, HEWL represents no substrate for mTG. Likewise, enzymatic treatment following a pretreatment with high pressure did not lead to oligomerization. Reactive amino acid side chains were identified by peptide mapping after tryptic digestion using RP-HPLC with ESI-TOF-MS. Isopeptide-containing peptide fragments were found only in HEWL samples simultaneously treated with enzyme and pressure. It was found that mTG exclusively cross-links HEWL under high pressure by formation of an isopeptide between lysine at position 1 and glutamine at position 121 in the peptide chain. Therefore, a pressure-induced partial and reversible unfolding of the protein with exposure of lysine and glutamine side chains has to occur, resulting in a site-directed oligomerization of HEWL by mTG. The enzymatic modification of HEWL by mTG under high pressure offers interesting perspectives for further functionalization reactions.
Collapse
Affiliation(s)
- Susanne Schuh
- Institute of Food Chemistry, Technische Universität Dresden, D-01062 Dresden, Germany
| | | | | |
Collapse
|
17
|
Stachel I, Schwarzenbolz U, Henle T, Meyer M. Cross-linking of type I collagen with microbial transglutaminase: identification of cross-linking sites. Biomacromolecules 2010; 11:698-705. [PMID: 20131754 DOI: 10.1021/bm901284x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Collagen is a popular biomaterial. To deal with its lack of thermal stability and its weak resistance to proteolytic degradation, collagen-based materials are stabilized via different cross-linking procedures. Regarding the potential toxicity of residual cross-linking agents, enzyme-mediated cross-linking would provide an alternative and nontoxic method for collagen stabilization. The results of this study show that type I collagen is a substrate for mTG. However, epsilon-(gamma-glutamyl)lysine cross-links are only incorporated at elevated temperatures when the protein is partially or completely denatured. A maximum number of 5.4 cross-links per collagen monomer were found for heat-denatured collagen. Labeling with the primary amine monodansylcadaverine revealed that at least half of the cross-links are located within the triple helical region of the collagen molecule. Because the triple helix is highly ordered in its native state, this finding might explain why the glutamine residues are inaccessible for mTG under nondenaturing conditions.
Collapse
Affiliation(s)
- Ines Stachel
- Research Institute for Leather and Plastic Sheeting, Meibetaner Ring 1-5, 09599 Freiberg, Germany.
| | | | | | | |
Collapse
|
18
|
Ehrlich H, Hanke T, Simon P, Born R, Fischer C, Frolov A, Langrock T, Hoffmann R, Schwarzenbolz U, Henle T, Bazhenov VV, Worch H. Carboxymethylation of the fibrillar collagen with respect to formation of hydroxyapatite. J Biomed Mater Res B Appl Biomater 2010; 92:542-51. [PMID: 19957363 DOI: 10.1002/jbm.b.31551] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Control over crystal growth by acidic matrix macromolecules is an important process in the formation of many mineralized tissues. Highly acidic macromolecules are postulated intermediates in tissue mineralization, because they sequester many calcium ions and occur in high concentrations at mineralizing foci in distantly related organisms. A prerequisite for biomineralization is the ability of cations like calcium to bind to proteins and to result in concert with appropriate anions like phosphates or carbonates in composite materials with bone-like properties. For this mineralization process the proteins have to be modified with respect to acidification. In this study we modified the protein collagen by carboxymethylation using glucuronic acid. Our experiments showed unambigously, that N(epsilon)-carboxymethyllysine is the major product of the in vitro nonenzymatic glycation reaction between glucuronic acid and collagen. We hypothesized that the function of biomimetically carboxymethylated collagen is to increase the local concentration of corresponding ions so that a critical nucleus of ions can be formed, leading to the formation of the mineral. Thus, the self-organization of HAP nanocrystals on and within collagen fibrils was intensified by carboxymethylation.
Collapse
Affiliation(s)
- Hermann Ehrlich
- Institute of Bioanalytical Chemistry, TU Dresden, Dresden, 01069 Germany.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Adebowale K, Henle T, Schwarzenbolz U, Doert T. Modification and properties of African yam bean (Sphenostylis stenocarpa Hochst. Ex A. Rich.) Harms starch I: Heat moisture treatments and annealing. Food Hydrocoll 2009. [DOI: 10.1016/j.foodhyd.2009.01.002] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
20
|
Menéndez O, Schwarzenbolz U, Partschefeld C, Henle T. Affinity of microbial transglutaminase to αs1-, β-, and acid casein under atmospheric and high pressure conditions. J Agric Food Chem 2009; 57:4177-4184. [PMID: 19368390 DOI: 10.1021/jf8034447] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Kinetics for the reaction of microbial transglutaminase (MTG) with individual caseins in a TRIS-acetate buffer at pH 6.0 was evaluated under atmospheric pressure (0.1 MPa) and high pressure (400 MPa) at 40 °C. The reaction was monitored under the following limitations: The kinetics from the initial velocities was obtained from nonprogressive enzymatic reactions assuming that the individual catalytic constants of reactive glutamine residues are represented by the reaction between MTG and casein monomers. Enzyme reaction kinetics carried out at 0.1 MPa at 40 °C showed Henri-Michaelis-Menten behavior with maximal velocities of 2.7 ± 0.02 × 10(-3), 0.8 ± 0.01 × 10(-3), and 1.3 ± 0.30 × 10(-3) mmol/L · min and K(m) values of 59 ± 2 × 10(-3), 64 ± 3 × 10(-3), and 50 ± 2 × 10(-3) mmol/L for β-, α(s1)-, and acid casein, respectively. Enzyme reaction kinetics of β-casein carried out at 400 MPa and 40 °C also showed a Henri-Michaelis-Menten behavior with a similar maximal velocity of 2.5 ± 0.33 × 10(-3) mmol/L · min, but, comparable to a competitive inhibition, the K(m) value increased to 144 ± 34 × 10(-3) mmol/L. The reaction of MTG with α(s1)-casein under high pressure did not fit in to Henri-Michaelis-Menten kinetics, indicating the complex influence of pressure on protein-enzyme interactions.
Collapse
Affiliation(s)
- Orquídea Menéndez
- Institute of Food Chemistry, Technische Universität Dresden, D-01062 Dresden, Germany
| | | | | | | |
Collapse
|
21
|
Ehrlich H, Hanke T, Frolov A, Langrock T, Hoffmann R, Fischer C, Schwarzenbolz U, Henle T, Born R, Worch H. Modification of collagen in vitro with respect to formation of Nɛ-carboxymethyllysine. Int J Biol Macromol 2009; 44:51-6. [DOI: 10.1016/j.ijbiomac.2008.10.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Revised: 10/01/2008] [Accepted: 10/01/2008] [Indexed: 10/21/2022]
|
22
|
Ehrlich H, Hanke T, Born R, Fischer C, Frolov A, Langrock T, Hoffmann R, Schwarzenbolz U, Henle T, Simon P, Geiger D, Bazhenov VV, Worch H. Mineralization of biomimetically carboxymethylated collagen fibrils in a model dual membrane diffusion system. J Memb Sci 2009. [DOI: 10.1016/j.memsci.2008.10.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
23
|
|
24
|
|
25
|
Partschefeld C, Richter S, Schwarzenbolz U, Henle T. Modification of β-lactoglobulin by microbial transglutaminase under high hydrostatic pressure: Localization of reactive glutamine residues. Biotechnol J 2007; 2:462-8. [PMID: 17373648 DOI: 10.1002/biot.200600226] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Microbial transglutaminase (mTG) mediated modification of bovine beta-lactoglobulin (bLG) at ambient and high hydrostatic pressure was investigated in order to characterize preferred sites of the crosslinking reaction by identifying reactive glutamine residues. bLG was labeled with triglycine (GGG) by incubation with mTG at ambient pressure or at 400 MPa, respectively, and was subjected to an enzymatic digestion with trypsin. The resulting peptides were separated and those containing glutamine residues modified with GGG were unambiguously identified using RP-HPLC with ESI-TOF-MS. For bLG treated with mTG at ambient pressure for 1 h at 40 degrees C, no labeling was observed, thus confirming that the native protein is no substrate for mTG. After incubation of the protein with mTG at 400 MPa for 1 h at 40 degrees C, four out of nine glutamine residues, namely at positions 5, 13, 35, and 59 were identified as accessible for the mTG catalyzed reaction, indicating partial unfolding of bLG under pressure and exposure of previously unaccesible glutamine residues. Thus, only a limited number of glutamine residues were substrates for mTG, which points to a pronounced substrate specificity of mTG toward individual glutamine residues within a protein.
Collapse
|
26
|
Partschefeld C, Schwarzenbolz U, Richter S, Henle T. Crosslinking of casein by microbial transglutaminase and its resulting influence on the stability of micelle structure. Biotechnol J 2007; 2:456-61. [PMID: 17309046 DOI: 10.1002/biot.200600232] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The influence of enzymatic crosslinking by microbial transglutaminase (mTG) on the stability of casein micelles of ultrahigh temperature (UHT)-treated milk in the presence of EDTA (0-0.45 mM) or ethanol (0-74 vol%) as well as under high hydrostatic pressures up to 400 MPa was investigated. Disintegration of micelles and changes in micelle size were monitored by the measurement of turbidity as well as by dynamic light scattering. The results show that the incubation of UHTtreated milk with mTG resulted in an improved micelle stability toward disintegration on addition of EDTA, ethanol, or pressure treatment. Intramicellar formed isopetides significantly enhanced the stability of casein micelles. It is supposed that net-like crosslinks are formed within the external region of the micelles and they adopt the stabilizing role of colloidal calcium phosphate within the micelles, thus making the micelles less contestable for disrupting influences.
Collapse
|
27
|
Menéndez O, Rawel H, Schwarzenbolz U, Henle T. Structural changes of microbial transglutaminase during thermal and high-pressure treatment. J Agric Food Chem 2006; 54:1716-21. [PMID: 16506824 DOI: 10.1021/jf0522863] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The activity of microbial transglutaminase (MTG) and the corresponding secondary structure, measured by circular dichroism (CD), was analyzed before and after treatment at different temperatures (40 and 80 degrees C) and pressures (0.1, 200, 400, 600 MPa). Irreversible enzyme inactivation was achieved after 2 min at 80 degrees C and 0.1 MPa. Enzyme inactivation at 0.1, 200, 400, and 600 MPa and 40 degrees C followed first-order kinetics. The enzyme showed residual activity of 50% after 12 min at 600 MPa and 40 degrees C. Mobility of aromatic side chains of the enzyme molecule was observed in all temperature- and/or pressure-treated samples; however, high-pressure treatment at 600 MPa induced a loss of tertiary structure and a significant decrease in the alpha-helix content. The relative content of beta-strand substructures was significantly increased after 30 min at 600 MPa and 40 degrees C or 2 min at 0.1 MPa and 80 degrees C. We conclude that the active center of MTG, which is located in an expanded beta-strand domain, is resistant to high hydrostatic pressure and pressure-induced inactivation is caused by destruction of alpha-helix elements with a corresponding influence on the enzyme stability in solution.
Collapse
Affiliation(s)
- Orquídea Menéndez
- Institute of Food Chemistry, Technische Universität Dresden, Germany
| | | | | | | |
Collapse
|
28
|
Abstract
Casein solutions (5% w/v) were treated with microbial transglutaminase (MTG) and glucono-delta-lactone (GDL) under varying conditions in order to obtain gels. Storage modulus (G') and gelation time of the gels were measured by oscillation rheometry, while protein cross-linking was determined by gel permeation chromatography. The addition of only GDL to milk resulted in very weak gels, while MTG on its own was not able to create gel networks. Simultaneous action of both ingredients led to gels, the firmness of which was linearly related to the added amount of MTG, but passed through a maximum with rising GDL concentrations. Using chromatographical analysis, increasing G' values were interrelated with the formation of MTG-induced oligomers. The gelation time was directly proportional to the GDL concentration but not influenced by the addition of MTG within the studied range of concentration.
Collapse
Affiliation(s)
- Orquídea Meneńdez
- Institute of Food Chemistry, Technical University of Dresden, D-01062 Dresden, Germany
| | | | | | | |
Collapse
|
29
|
Schwarzenbolz U, Klostermeyer H, Henle T. Maillard reaction under high hydrostatic pressure: studies on the formation of protein-bound amino acid derivatives. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s0531-5131(02)01003-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
30
|
Schwarzenbolz U, Klostermeyer H, Henle T. Maillard-type reactions under high hydrostatic pressure: Formation of pentosidine. Eur Food Res Technol 2000. [DOI: 10.1007/s002170050025] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
31
|
|