d-Galacturonic Acid: A Highly Reactive Compound in Nonenzymatic Browning. 2. Formation of Amino-Specific Degradation Products

2015 ◽  
Vol 63 (28) ◽  
pp. 6457-6465 ◽  
Author(s):  
Steffen Wegener ◽  
Maria-Anna Bornik ◽  
Lothar W. Kroh
Keyword(s):  
Galacturonic Acid ◽  
Degradation Products ◽  
Nonenzymatic Browning ◽  
Reactive Compound ◽  
Specific Degradation

THE ROLE OF VARIOUS HAEMOSTASIS PARAMETERS IN MONITORING FIBRINOLYSIS WITH PRO-UROKINASE/STREPTOKINASE IN TREATMENT OF MYOCARDIAL INFARCTION

1987 ◽  
Author(s):  
F Keller ◽  
P Schanzenbächer ◽  
F Dati ◽  
J Huber ◽  
K kochsiek
Keyword(s):  
Myocardial Infarction ◽  
Degradation Products ◽  
Therapy Monitoring ◽  
Latex Agglutination ◽  
Systemic Activity ◽  
Thromboplastic Activity ◽  
Specific Degradation ◽  
D Dimer

The new drug pro-urokinase, a proenzyme of urokinase (scu-PA), seems to have advantages in comparison with other fibrinolytic agents. Properties like higher fibrin specifity, non-systemic activity and lower antigenity may lead to a lower rate of complications. In a pilot study 10 patients with acute myocardial infarction have been treated under angiographical control with pro-urokinase (3-9 millions IU) by i.v. application. In case of no perfusion a further administration of streptokinase was carried on. The blood samples were obtained at therapy begin and after 5, 10, 30, 60 and 120 minutes. The therapy monitoring was performed by determination of established haemostasis parameters, like fibrinogen, fibrin(ogen)-split products (FSP), a2-antiplasmin. Plasminogen and batroxobin-time. Furthermore, the diagnostic relevance of new laboratory tests for fibrinolysis, D-Dimer and thrombin-anti thrombin Ill-complex (TAT) has been investigated considering some typical follow-ups. D-Dimer were determined by latex agglutination test and TAT by enzyme immunoassay.Generally the application of pro-urokinase in contrast to streptokinase results in minimal changes of the classic fibrinolysis parameters like fibrinogen, FSP, batroxobin-time etc. demonstrating no systemic lysis. The appearance of plasmic degradation products of cross-linked fibrin (D-Dimer) is a specific indi-cater of the release of thrombotic material. Other non-specific degradation products (fibrinogenolysis) were detected by the measurement of FSP. In some cases in which perfusion ocurred an increase of TAT followed by a rapid decrease was observed. This indicates a higher thromboplastic activity which may originate from the infarcted area producing TAT complex formation.

Specific degradation of pectins via a carbodiimide-mediated Lossen rearrangement of methyl esterified galacturonic acid residues

2001 ◽  
Vol 333 (1) ◽  
pp. 47-58 ◽  
Author(s):  
Paul W Needs ◽  
Neil M Rigby ◽  
Stephen G Ring ◽  
Alistair J MacDougall
Keyword(s):  
Galacturonic Acid ◽  
Specific Degradation

Incorporation of 13C-Labeled Coniferyl Alcohol into Developing Ginkgo biloba L. Lignin Revealed by Analytical Pyrolysis and CuO Oxidation in Combination with Isotope Ratio Monitoring-Gas Chromatography-Mass Spectrometry

Holzforschung ◽  
2000 ◽  
Vol 54 (1) ◽  
pp. 39-54 ◽  
Author(s):  
T. I. Eglinton ◽  
M. A. Goñi ◽  
J. J. Boon ◽  
E. R. E. van der Hage ◽  
N. Terashima ◽  
...  
Keyword(s):  
Ginkgo Biloba ◽  
Degradation Products ◽  
Chemical Degradation ◽  
Original Position ◽  
Side Chain ◽  
Analytical Pyrolysis ◽  
Isotopic Analyses ◽  
Specific Degradation ◽  
Lignin Macromolecule ◽  
Cuo Oxidation

Summary A suite of four samples of xylem tissue from Ginkgo (Ginkgo biloba L.) shoots grown in a medium containing coniferin 13C-labeled at differing side-chain carbon atoms were studied using thermal and chemical degradation methods in combination with molecular-level isotopic analyses. The aims of the study were threefold: (1) to verify conclusions drawn from Nuclear Magnetic Resonance experiments previously performed on the same tissue samples, (2) to investigate degradation mechanisms and (3) to quantify the proportion of labeled material in each sample. Isotopic analysis of specific degradation products revealed the presence of the label exclusively within lignin-derived (phenolic) products and that the label is retained in its original position on the side-chain. These two results clearly indicate that there is no “scrambling” of carbon atoms as a result of thermal or chemical degradation, and thus lend strong support to analytical pyrolysis and chemolysis as viable approaches for structural investigations of the lignin macromolecule. Indeed, the isotopic enrichment of specific degradation products provides new evidence for certain types of linkages within the lignin polymer. The distribution and isotopic composition of the degradation products also strongly suggest an origin from newly-formed lignin as opposed to DHP-type products or unreacted substrate. As such, the data provides added confidence in the selective labeling approach for elucidation of the structure and biosynthesis of lignin. Isotopic mass balance calculations reveal that certain pyrolysis and CuO oxidation products show enhanced labeling which may be indicative of preferential incorporation of their specific precursors into the growing lignin macromolecule or heterogeneous lignin deposition.

Nonenzymatic browning reactions of retro-aldol degradation products of carbohydrates

1999 ◽  
Vol 209 (3-4) ◽  
pp. 261-265 ◽  
Author(s):  
Bettina Cämmerer ◽  
Bronislaw L. Wedzicha ◽  
L. W. Kroh
Keyword(s):  
Degradation Products ◽  
Nonenzymatic Browning

The hex-5-enose degradation: cleavage of glycosiduronic acid linkages in modified methylated Sterculia gums

1987 ◽  
Vol 65 (9) ◽  
pp. 2069-2076 ◽  
Author(s):  
Gerald Oliver Aspinall ◽  
Lev Khondo ◽  
Bruce Alan Williams
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Galacturonic Acid ◽  
Uronic Acid ◽  
Zinc Dust ◽  
Degradation Products ◽  
Compositional Analysis ◽  
Mass Spectral Data ◽  
Mass Spectral

Reduction of uronic acid residues in permethylated polysaccharides from Sterculiaurens and S. caudata gums, followed by transformation of the resulting hexose into 6-deoxy-6-iodohexose residues, affords modified polysaccharides that undergo depolymerization on treatment with zinc dust. The main products after reduction with sodium borohydride are hexenitolterminated oligosaccharides. Their structures have been assigned as members of a series of O-[α-L-rhamnopyranosyl]-(1 → 3)-1,2-dideoxyhex-1-enitol derivatives, with and without attendant β-D-galactopyranosyl substituents, on the basis of nuclear magnetic resonance and mass spectral data and compositional analysis of trideuteriomethylated derivatives. The structures of the polysaccharides have been reassessed in the light of these and other experiments, and may now be formulated as containing a backbone of alternating 4-linked α-D-galacturonic acid and 2-linked α-L-rhamnopyranose residues bearing a minimum of three types of side chains attached at specific sites. Characterization of some of the degradation products provides evidence that limited degradation had occurred during methylation of the glycuronans.

scholarly journals The Expression of Thrombospondin-4 Correlates with Disease Severity in Osteoarthritic Knee Cartilage

2019 ◽  
Vol 20 (2) ◽  
pp. 447 ◽  
Author(s):  
Kathrin Maly ◽  
Inna Schaible ◽  
Jana Riegger ◽  
Rolf Brenner ◽  
Andrea Meurer ◽  
...  
Keyword(s):  
Protein Extraction ◽  
Degradation Products ◽  
Joint Disease ◽  
Transcriptional Level ◽  
Matrix Remodeling ◽  
Knee Cartilage ◽  
Cartilage Extracellular Matrix ◽  
Specific Degradation ◽  
Thrombospondin 4 ◽  
Extracellular Glycoprotein

Osteoarthritis (OA) is a progressive joint disease characterized by a continuous degradation of the cartilage extracellular matrix (ECM). The expression of the extracellular glycoprotein thrombospondin-4 (TSP-4) is known to be increased in injured tissues and involved in matrix remodeling, but its role in articular cartilage and, in particular, in OA remains elusive. In the present study, we analyzed the expression and localization of TSP-4 in healthy and OA knee cartilage by reverse transcription polymerase chain reaction (RT-PCR), immunohistochemistry, and immunoblot. We found that TSP-4 protein expression is increased in OA and that expression levels correlate with OA severity. TSP-4 was not regulated at the transcriptional level but we detected changes in the anchorage of TSP-4 in the altered ECM using sequential protein extraction. We were also able to detect pentameric and fragmented TSP-4 in the serum of both healthy controls and OA patients. Here, the total protein amount was not significantly different but we identified specific degradation products that were more abundant in sera of OA patients. Future studies will reveal if these fragments have the potential to serve as OA-specific biomarkers.

scholarly journals Novel Mechanism and Kinetics of Tetramethrin Degradation Using an Indigenous Gordonia cholesterolivorans A16

2021 ◽  
Vol 22 (17) ◽  
pp. 9242
Author(s):  
Yuxin Guo ◽  
Yaohua Huang ◽  
Shimei Pang ◽  
Tianhao Zhou ◽  
Ziqiu Lin ◽  
...  
Keyword(s):  
Contaminated Soils ◽  
High Performance ◽  
Degradation Rate ◽  
Degradation Products ◽  
Living System ◽  
Gas Chromatography Mass Spectrometry ◽  
Synthetic Pyrethroids ◽  
Half Saturation Constant ◽  
Important Concern ◽  
Specific Degradation

Tetramethrin is a pyrethroid insecticide that is commonly used worldwide. The toxicity of this insecticide into the living system is an important concern. In this study, a novel tetramethrin-degrading bacterial strain named A16 was isolated from the activated sludge and identified as Gordonia cholesterolivorans. Strain A16 exhibited superior tetramethrin degradation activity, and utilized tetramethrin as the sole carbon source for growth in a mineral salt medium (MSM). High-performance liquid chromatography (HPLC) analysis revealed that the A16 strain was able to completely degrade 25 mg·L−1 of tetramethrin after 9 days of incubation. Strain A16 effectively degraded tetramethrin at temperature 20–40 °C, pH 5–9, and initial tetramethrin 25–800 mg·L−1. The maximum specific degradation rate (qmax), half-saturation constant (Ks), and inhibition constant (Ki) were determined to be 0.4561 day−1, 7.3 mg·L−1, and 75.2 mg·L−1, respectively. The Box–Behnken design was used to optimize degradation conditions, and maximum degradation was observed at pH 8.5 and a temperature of 38 °C. Five intermediate metabolites were identified after analyzing the degradation products through gas chromatography–mass spectrometry (GC-MS), which suggested that tetramethrin could be degraded first by cleavage of its carboxylester bond, followed by degradation of the five-carbon ring and its subsequent metabolism. This is the first report of a metabolic pathway of tetramethrin in a microorganism. Furthermore, bioaugmentation of tetramethrin-contaminated soils (50 mg·kg−1) with strain A16 (1.0 × 107 cells g−1 of soil) significantly accelerated the degradation rate of tetramethrin, and 74.1% and 82.9% of tetramethrin was removed from sterile and non-sterile soils within 11 days, respectively. The strain A16 was also capable of efficiently degrading a broad spectrum of synthetic pyrethroids including D-cyphenothrin, chlorempenthrin, prallethrin, and allethrin, with a degradation efficiency of 68.3%, 60.7%, 91.6%, and 94.7%, respectively, after being cultured under the same conditions for 11 days. The results of the present study confirmed the bioremediation potential of strain A16 from a contaminated environment.

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