Photobiocatalytic decarboxylation for olefin synthesis

2015 ◽  
Vol 51 (10) ◽  
pp. 1918-1921 ◽  
Author(s):  
Ioannis Zachos ◽  
Sarah Katharina Gaßmeyer ◽  
Daniel Bauer ◽  
Volker Sieber ◽  
Frank Hollmann ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Fatty Acids ◽  
Fatty Acid ◽  
High Selectivity ◽  
Acid Decarboxylase ◽  
Oxidative Decarboxylation ◽  
Efficient System ◽  
Olefin Synthesis ◽  
Terminal Alkenes

The oxidative decarboxylation of fatty acids to terminal alkenes was accomplished with high selectivity by combining a fatty acid decarboxylase OleTJE with the light-catalyzed generation of the cosubstrate hydrogen peroxide, resulting in a simple and efficient system for the light-driven cleavage of C–C bonds.

scholarly journals Acetyl-CoA from inflammation-induced fatty acids oxidation promotes hepatic malate-aspartate shuttle activity and glycolysis

2018 ◽  
Vol 315 (4) ◽  
pp. E496-E510 ◽  
Author(s):  
Tongxin Wang ◽  
Weilei Yao ◽  
Ji Li ◽  
Qiongyu He ◽  
Yafei Shao ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Oxidation ◽  
Lactate Production ◽  
Acid Oxidation ◽  
Oxidative Decarboxylation ◽  
Nutrient Metabolism ◽  
Acetyl Coa ◽  
Inflammatory Stress ◽  
Malate Aspartate Shuttle

Hepatic metabolic syndrome is associated with inflammation, as inflammation stimulates the reprogramming of nutrient metabolism and hepatic mitochondria-generated acetyl-CoA, but how acetyl-CoA affects the reprogramming of nutrient metabolism, especially glucose and fatty acids, in the condition of inflammation is still unclear. Here, we used an acute inflammation model in which pigs were injected with lipopolysaccharide (LPS) and found that hepatic glycolysis and fatty acid oxidation are both promoted. Acetyl-proteome profiling of LPS-infected pigs liver showed that inflammatory stress exacerbates the acetylation of mitochondrial proteins. Both mitochondrial glutamate oxaloacetate transaminase 2 (GOT2) and malate dehydrogenase 2 (MDH2) were acetylated, and the malate-aspartate shuttle (MAS) activity was stimulated to maintain glycolysis. With the use of 13C-carbon tracing in vitro, acetyl-CoA was found to be mainly supplied by lipid-derived fatty acid oxidation rather than glucose-derived pyruvate oxidative decarboxylation, while glucose was mainly used for lactate production in response to inflammatory stress. The results of the mitochondrial experiment showed that acetyl-CoA directly increases MDH2 and, in turn, the GOT2 acetylation level affects MAS activity. Treatment with palmitate in primary hepatocytes from LPS-injected pigs increased the hepatic production of acetyl-CoA, pyruvate, and lactate; MAS activity; and hepatic MDH2 and GOT2 hyperacetylation, while the deficiency of long-chain acetyl-CoA dehydrogenase resulted in the stabilization of these parameters. These observations suggest that acetyl-CoA produced by fatty acid oxidation promotes MAS activity and glycolysis via nonenzymatic acetylation during the inflammatory stress response.

scholarly journals THE NATURE OF SERUM ANTITRYPSIN

1914 ◽  
Vol 19 (5) ◽  
pp. 459-479 ◽  
Author(s):  
James W. Jobling ◽  
William Petersen
Keyword(s):  
Hydrogen Peroxide ◽  
Fatty Acids ◽  
Fatty Acid ◽  
Potassium Iodide ◽  
Unsaturated Fatty Acids ◽  
Serum Lipase ◽  
Enzyme Action ◽  
Inhibiting Action

1. The ferment-inhibiting action of the serum is due to the presence of compounds of the unsaturated fatty acids. 2. These fatty acid compounds may be removed from the serum by means of chloroform or ether. 3. Soaps prepared by saponifying the chloroform or ether extracts inhibit the action of trypsin. 4. The anti-enzyme action of the serum can be removed by filtering acid serum through kaolin, and can in part be restored by extracting the kaolin. 5. The decrease in strength of anti-enzyme in old sera is probably due to the action of the serum lipase. 6. Iodin, potassium iodide, or hydrogen peroxide remove the inhibiting action of the serum. 7. Soaps of the unsaturated fatty acids lose their ferment-inhibiting action when heated with serum at 70° C.

scholarly journals Lipidomics reveal the protective effects of a vegetable-derived isothiocyanate against retinal degeneration

F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 1067 ◽  
Author(s):  
Faith A. Kwa ◽  
Nabeela K. Dulull ◽  
Ute Roessner ◽  
Daniel A. Dias ◽  
Thusitha W. Rupasinghe
Keyword(s):  
Oxidative Stress ◽  
Mass Spectrometry ◽  
Hydrogen Peroxide ◽  
Fatty Acids ◽  
Cell Proliferation ◽  
Fatty Acid ◽  
Oxidative Damage ◽  
Disease Progression ◽  
Protective Effects ◽  
Retinal Cells

Background: Age-related macular degeneration (AMD) is a leading cause of blindness in the ageing population. Without effective treatment strategies that can prevent disease progression, there is an urgent need for novel therapeutic interventions to reduce the burden of vision loss and improve patients’ quality of life. Dysfunctional innate immune responses to oxidative stress observed in AMD can be caused by the formation of oxidised lipids, whilst polyunsaturated fatty acids have shown to increase the risk of AMD and disease progression in affected individuals. Previously, our laboratory has shown that the vegetable-derived isothiocyanate, L-sulforaphane (LSF), can protect human adult pigment epithelial cells from oxidative damage by upregulating gene expression of the oxidative stress enzyme Glutathione-S-Transferase µ1. This study aims to validate the protective effects of LSF on human retinal cells under oxidative stress conditions and to reveal the key players in fatty acid and lipid metabolism that may facilitate this protection. Methods: The in vitro oxidative stress model of AMD was based on the exposure of an adult retinal pigment epithelium-19 cell line to 200µM hydrogen peroxide. Percentage cell proliferation following LSF treatment was measured using tetrazolium salt-based assays. Untargeted fatty acid profiling was performed by gas chromatography-mass spectrometry. Untargeted lipid profiling was performed by liquid chromatography-mass spectrometry. Results: Under hydrogen peroxide-induced oxidative stress conditions, LSF treatment induced dose-dependent cell proliferation. The key fatty acids that were increased by LSF treatment of the retinal cells include oleic acid and eicosatrienoic acid. LSF treatment also increased levels of the lipid classes phosphatidylcholine, cholesteryl ester and oxo-phytodienoic acid but decreased levels of phosphatidylethanolamine lipids. Conclusions: We propose that retinal cells at risk of oxidative damage and apoptosis can be pre-conditioned with LSF to regulate levels of selected fatty acids and lipids known to be implicated in the pathogenesis and progression of AMD.

Catalytic deoxygenation of C18 fatty acid over supported metal Ni catalysts promoted by the basic sites of ZnAl2O4 spinel phase

2019 ◽  
Vol 9 (1) ◽  
pp. 213-222 ◽  
Author(s):  
Guangci Li ◽  
Lei Chen ◽  
Ruikun Fan ◽  
Di Liu ◽  
Song Chen ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
High Selectivity ◽  
Spinel Phase ◽  
Ni Catalysts ◽  
Basic Sites ◽  
Catalytic Deoxygenation ◽  
Znal2o4 Spinel ◽  
Basic Strength ◽  
Supported Metal

The supports with various amounts of Zn–Al spinel were synthesized to test catalytic deoxygenation activity of fatty acids, which show that spinel phase increased the basic strength of the catalyst, resulting in a high selectivity to hydrocarbons.

scholarly journals Lipidomic Analysis of Plastidial Octanoyltransferase Mutants of Arabidopsis thaliana

Metabolites ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 209 ◽  
Author(s):  
Raquel Martins-Noguerol ◽  
Antonio Javier Moreno-Pérez ◽  
Sebastien Acket ◽  
Salim Makni ◽  
Rafael Garcés ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Arabidopsis Thaliana ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Oxidative Decarboxylation ◽  
Acetyl Coa ◽  
Seed Point ◽  
Lipid Species ◽  
Lipoyl Synthase

Plant de novo fatty acid synthesis takes place in the plastid using acetyl-coenzyme A (acetyl-CoA) as the main precursor. This first intermediate is produced from pyruvate through the action of the plastidial pyruvate dehydrogenase complex (PDH), which catalyses the oxidative decarboxylation of pyruvate to produce acetyl-CoA, CO2, and NADH. For the proper functioning of this complex, lipoic acid is required to be bound to the dihydrolipoamide S-acetyltransferase E2 subunit of PDH. Octanoyltransferase (LIP2; EC 2.3.1.181) and lipoyl synthase (LIP1; EC 2.8.1.8) are the enzymes involved in the biosynthesis of this essential cofactor. In Arabidopsis plastids, an essential lipoyl synthase (AtLIP1p) and two redundant octanoyltransferases (AtLIP2p1 and AtLIP2p2) have been described. In the present study, the lipidomic characterization of Arabidopsis octanoyltransferase mutants reveals new insight into the lipoylation functions within plastid metabolism. Lipids and fatty acids from mature seeds and seedlings from Atlip2p1 and Atlip2p2 mutants were analysed by gas chromatography (GC) and liquid chromatography–electrospray ionization high-resolution mass spectrometry (LC-ESI-HRMS2), the analysis revealed changes in fatty acid profiles that showed similar patterns in both mutant seeds and seedlings and in the lipid species containing those fatty acids. Although both mutants showed similar tendencies, the lack of the AtLIP2p2 isoform produced a more acute variation in its lipids profile. These changes in fatty acid composition and the increase in their content per seed point to the interference of octanoyltransferases in the fatty acid synthesis flux in Arabidopsis thaliana seeds.

scholarly journals In vitro oxidative decarboxylation of free fatty acids to terminal alkenes by two new P450 peroxygenases

2017 ◽  
Vol 10 (1) ◽  
Author(s):  
Huifang Xu ◽  
Linlin Ning ◽  
Wenxia Yang ◽  
Bo Fang ◽  
Cong Wang ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Oxidative Decarboxylation ◽  
Terminal Alkenes

scholarly journals Lipidomics reveal the protective effects of a vegetable-derived isothiocyanate against retinal degeneration

F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 1067
Author(s):  
Faith A. Kwa ◽  
Nabeela K. Dulull ◽  
Ute Roessner ◽  
Daniel A. Dias ◽  
Thusitha W. Rupasinghe
Keyword(s):  
Oxidative Stress ◽  
Mass Spectrometry ◽  
Hydrogen Peroxide ◽  
Fatty Acids ◽  
Cell Proliferation ◽  
Fatty Acid ◽  
Oxidative Damage ◽  
Disease Progression ◽  
Protective Effects ◽  
Retinal Cells

Background: Age-related macular degeneration (AMD) is a leading cause of blindness in the ageing population. Without effective treatment strategies that can prevent disease progression, there is an urgent need for novel therapeutic interventions to reduce the burden of vision loss and improve patients’ quality of life. Dysfunctional innate immune responses to oxidative stress observed in AMD can be caused by the formation of oxidised lipids, whilst polyunsaturated fatty acids have shown to increase the risk of AMD and disease progression in affected individuals. Previously, our laboratory has shown that the vegetable-derived isothiocyanate, L-sulforaphane (LSF), can protect human adult pigment epithelial cells from oxidative damage by upregulating gene expression of the oxidative stress enzyme Glutathione-S-Transferase µ1. This study aims to validate the protective effects of LSF on human retinal cells under oxidative stress conditions and to reveal the key players in fatty acid and lipid metabolism that may facilitate this protection. Methods: The in vitro oxidative stress model of AMD was based on the exposure of an adult retinal pigment epithelium-19 cell line to 200µM hydrogen peroxide. Percentage cell proliferation following LSF treatment was measured using tetrazolium salt-based assays. Untargeted fatty acid profiling was performed by gas chromatography-mass spectrometry. Untargeted lipid profiling was performed by liquid chromatography-mass spectrometry. Results: Under hydrogen peroxide-induced oxidative stress conditions, LSF treatment induced dose-dependent cell proliferation. The key fatty acids that were increased by LSF treatment of the retinal cells include oleic acid and eicosatrienoic acid. LSF treatment also increased levels of the lipid classes phosphatidylcholine, cholesteryl ester and oxo-phytodienoic acid but decreased levels of phosphatidylethanolamine lipids. Conclusions: We propose that retinal cells at risk of oxidative damage and apoptosis can be pre-conditioned with LSF to regulate levels of selected fatty acids and lipids known to be implicated in the pathogenesis and progression of AMD.

scholarly journals Hydrogen peroxide-independent production of α-alkenes by OleTJE P450 fatty acid decarboxylase

2014 ◽  
Vol 7 (1) ◽  
pp. 28 ◽  
Author(s):  
Yi Liu ◽  
Cong Wang ◽  
Jinyong Yan ◽  
Wei Zhang ◽  
Wenna Guan ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Fatty Acid ◽  
Acid Decarboxylase

scholarly journals Lipidomics reveal the protective effects of a vegetable-derived isothiocyanate against retinal degeneration

F1000Research ◽  
2020 ◽  
Vol 8 ◽  
pp. 1067
Author(s):  
Faith A. Kwa ◽  
Nabeela K. Dulull ◽  
Ute Roessner ◽  
Daniel A. Dias ◽  
Thusitha W. Rupasinghe
Keyword(s):  
Oxidative Stress ◽  
Mass Spectrometry ◽  
Hydrogen Peroxide ◽  
Fatty Acids ◽  
Cell Proliferation ◽  
Fatty Acid ◽  
Oxidative Damage ◽  
Disease Progression ◽  
Protective Effects ◽  
Retinal Cells

Background: Age-related macular degeneration (AMD) is a leading cause of blindness in the ageing population. Without effective treatment strategies that can prevent disease progression, there is an urgent need for novel therapeutic interventions to reduce the burden of vision loss and improve patients’ quality of life. Dysfunctional innate immune responses to oxidative stress observed in AMD can be caused by the formation of oxidised lipids, whilst polyunsaturated fatty acids have shown to increase the risk of AMD and disease progression in affected individuals. Previously, our laboratory has shown that the vegetable-derived isothiocyanate, L-sulforaphane (LSF), can protect human adult pigment epithelial cells from oxidative damage by upregulating gene expression of the oxidative stress enzyme Glutathione-S-Transferase µ1. This study aims to validate the protective effects of LSF on human retinal cells under oxidative stress conditions and to reveal the key players in fatty acid and lipid metabolism that may facilitate this protection. Methods: The in vitro oxidative stress model of AMD was based on the exposure of an adult retinal pigment epithelium-19 cell line to 200µM hydrogen peroxide. Percentage cell proliferation following LSF treatment was measured using tetrazolium salt-based assays. Untargeted fatty acid profiling was performed by gas chromatography-mass spectrometry. Untargeted lipid profiling was performed by liquid chromatography-mass spectrometry. Results: Under hydrogen peroxide-induced oxidative stress conditions, LSF treatment induced dose-dependent cell proliferation. The key fatty acids that were increased by LSF treatment of the retinal cells include oleic acid and eicosatrienoic acid. LSF treatment also increased levels of the lipid classes phosphatidylcholine, cholesteryl ester and oxo-phytodienoic acid but decreased levels of phosphatidylethanolamine lipids. Conclusions: We propose that retinal cells at risk of oxidative damage and apoptosis can be pre-conditioned with LSF to regulate levels of selected fatty acids and lipids known to be implicated in the pathogenesis and progression of AMD.

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