Practical Asymmetric Enzymatic Reduction through Discovery of a Dehydrogenase-Compatible Biphasic Reaction Media†

2003 ◽  
Vol 5 (2) ◽  
pp. 173-176 ◽  
Author(s):  
Harald Gröger ◽  
Werner Hummel ◽  
Stefan Buchholz ◽  
Karlheinz Drauz ◽  
Tien Van Nguyen ◽  
...  
Keyword(s):  
Enzymatic Reduction ◽  
Biphasic Reaction ◽  
Reaction Media

scholarly journals Practical Asymmetric Enzymatic Reduction Through Discovery of a Dehydrogenase-Compatible Biphasic Reaction Media.

ChemInform ◽  
2003 ◽  
Vol 34 (21) ◽  
Author(s):  
Harald Groeger ◽  
Werner Hummel ◽  
Stefan Buchholz ◽  
Karlheinz Drauz ◽  
Nguyen Tien Van Nguyen Tien Van ◽  
...  
Keyword(s):  
Enzymatic Reduction ◽  
Biphasic Reaction ◽  
Reaction Media

Dimensionally-Controlled Hydrothermal Tm3+-doped Oxidic Nanocrystals and Their Photoluminescence Properties

2010 ◽  
Vol 1247 ◽  
Author(s):  
Rocío Calderón-Villajos ◽  
Carlos Zaldo ◽  
Concepción Cascales
Keyword(s):  
Single Crystals ◽  
Fluorescence Lifetimes ◽  
Photoluminescence Properties ◽  
Reaction Conditions ◽  
Hydrothermal Processes ◽  
Bulk Single Crystals ◽  
Template Free ◽  
Reaction Media

AbstractControlled reaction conditions in simple, template-free hydrothermal processes yield Tm-Lu2O3 and Tm-GdVO4 nanocrystals with well-defined specific morphologies and sizes. In both oxide families, nanocrystals prepared at pH 7 reaction media exhibit photoluminescence in ∼1.95 μm similar to bulk single crystals. For the lowest Tm3+ concentration (0.2 % mol) in GdVO4 measured 3H4 and 3F4 fluorescence lifetimes τ are very near to τrad.

Modular Simulation to Determine the Optimal Operating Policy of a Batch Reactor for the Enzymatic Fructose Reduction to Mannitol with the in situ Continuous Enzymatic Regeneration of the NAD Cofactor

2017 ◽  
Vol 68 (9) ◽  
pp. 2196-2203 ◽  
Author(s):  
Mara Crisan ◽  
Gheorghe Maria
Keyword(s):  
Batch Reactor ◽  
Production Capacity ◽  
Optimization Procedure ◽  
Enzymatic Reactions ◽  
Mannitol Dehydrogenase ◽  
Optimal Operating ◽  
Operating Policy ◽  
Enzymatic Reduction ◽  
Optimal Operating Policy

Novel coupled enzymatic systems reported important applications in the industrial bio-catalysis. Multi-enzymatic reactions can successfully replace complex chemical syntheses, using milder reaction conditions, and generating less waste. For such systems acting simultaneously, the model-based engineering calculations (design, reactor operation optimization) are difficult tasks, because they must account for interacting reactions, differences in enzymes optimal activity domains and deactivation kinetics. The determination of the optimal operating mode (enzyme ratios, enzyme feeding policy, temperature, pH) often turns into a difficult multi-objective optimization problem with multiple constraints to be solved for every particular system. The paper focuses on applying a modular screening procedure that can identify the optimal operating policy of an enzymatic reactor, which minimizes the enzyme consumption, given the process kinetic model, and an imposed production capacity. Following an optimization procedure, the process effectiveness is evaluated in a systematic approach, by including simple batch reactor (BR), batch with intermittent addition of the key-enzyme following certain optimal policies (BRP). Exemplification is made for the case of the enzymatic reduction of D-fructose to mannitol by using suspended MDH (mannitol dehydrogenase) and NADH (Nicotinamide adenine dinucleotide) cofactor, with the in-situ continuous regeneration of the cofactor by the expense of formate degradation in the presence of suspended FDH (Formate dehydrogenase).

Naturally Occurring Organic Acid-catalyzed Facile Diastereoselective Synthesis of Biologically Active (E)-3-(arylimino)indolin-2-one Derivatives in Water at Room Temperature

2019 ◽  
Vol 23 (16) ◽  
pp. 1778-1788 ◽  
Author(s):  
Gurpreet Kaur ◽  
Arvind Singh ◽  
Kiran Bala ◽  
Mamta Devi ◽  
Anjana Kumari ◽  
...  
Keyword(s):  
Room Temperature ◽  
Biologically Active ◽  
Environmentally Benign ◽  
Diastereoselective Synthesis ◽  
Substituted Anilines ◽  
Reaction Conditions ◽  
Naturally Occurring ◽  
Acid Catalyzed ◽  
Reaction Media ◽  
Column Chromatographic

A simple, straightforward and efficient method has been developed for the synthesis of (E)-3-(arylimino)indolin-2-one derivatives and (E)-2-((4-methoxyphenyl)imino)- acenaphthylen-1(2H)-one. The synthesis of these biologically-significant scaffolds was achieved from the reactions of various substituted anilines and isatins or acenaphthaquinone, respectively, using commercially available, environmentally benign and naturally occurring organic acids such as mandelic acid or itaconic acid as catalyst in aqueous medium at room temperature. Mild reaction conditions, energy efficiency, good to excellent yields, environmentally benign conditions, easy isolation of products, no need of column chromatographic separation and the reusability of reaction media are some of the significant features of the present protocol.

Synthesis, Characterization and Applications of Dicationic Ionic Liquids in Organic Synthesis

2020 ◽  
Vol 17 (4) ◽  
pp. 450-464
Author(s):  
Mohammad Javaherian ◽  
Seyyed Jafar Saghanezhad
Keyword(s):  
Ionic Liquids ◽  
Organic Synthesis ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Dicationic Ionic Liquids ◽  
Physical And Chemical ◽  
Reaction Media ◽  
And Chemical Properties

Dicationic ionic liquids are an emerging group of Ionic Liquids (ILs) that are currently receiving much attention as green reaction media and catalysts. Because of a great number of possible combinations of cations and anions, the physical and chemical properties of dicationic ionic liquids are more tunable and broader than monocationic ILs. Therefore, their unique properties have made them the target of many applied and fundamental researches. Actually, dicationic ionic liquids are more effective and rather fascinating than traditional monocationic ILs. So, due to greater versatility and diversity, their applications in organic synthesis have been extensively grown. In this review, we have focused on the synthesis, characterization and applications of dicationic ionic liquids, especially, in organic synthesis.

scholarly journals Effect of reaction media on the scavenging reaction of water-solubilized 2,2-diphenyl-1-picrylhydrazy radical by ascorbic acid

2021 ◽  
Vol 165 ◽  
pp. 55-56
Author(s):  
Ikuo Nakanishi ◽  
Yoshimi Shoji ◽  
Kei Ohkubo ◽  
Toshihiko Ozawa ◽  
Ken-ichiro Matsumoto ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Reaction Media

scholarly journals A Nitronaphthalimide Probe for Fluorescence Imaging of Hypoxia in Cancer Cells

2021 ◽  
Author(s):  
Rashmi Kumari ◽  
Vasumathy R ◽  
Dhanya Sunil ◽  
Raghumani Singh Ningthoujam ◽  
Badri Narain Pandey ◽  
...  
Keyword(s):  
Fluorescence Imaging ◽  
Tumor Hypoxia ◽  
Binding Pocket ◽  
Docking Studies ◽  
Single Step ◽  
Naphthalic Anhydride ◽  
Hypoxic Conditions ◽  
Fluorescence Measurements ◽  
Enzymatic Reduction

AbstractThe bioreductive enzymes typically upregulated in hypoxic tumor cells can be targeted for developing diagnostic and drug delivery applications. In this study, a new fluorescent probe 4−(6−nitro−1,3−dioxo−1H−benzo[de]isoquinolin−2(3H)−yl)benzaldehyde (NIB) based on a nitronaphthalimide skeleton that could respond to nitroreductase (NTR) overexpressed in hypoxic tumors is designed and its application in imaging tumor hypoxia is demonstrated. The docking studies revealed favourable interactions of NIB with the binding pocket of NTR-Escherichia coli. NIB, which is synthesized through a simple and single step imidation of 4−nitro−1,8−naphthalic anhydride displayed excellent reducible capacity under hypoxic conditions as evidenced from cyclic voltammetry investigations. The fluorescence measurements confirmed the formation of identical products (NIB-red) during chemical as well as NTR−aided enzymatic reduction in the presence of NADH. The potential fluorescence imaging of hypoxia based on NTR-mediated reduction of NIB is confirmed using in-vitro cell culture experiments using human breast cancer (MCF−7) cells, which displayed a significant change in the fluorescence colour and intensity at low NIB concentration within a short incubation period in hypoxic conditions. Graphical abstract

Sustainable synthesis of AFe2O4 (A= Mg, Zn, Mn) catalysts: comparing the photooxidative and electrochemical properties towards organic dyes detection and degradation

2021 ◽  
Author(s):  
Jeena N. Baby ◽  
Lavanya Chandrasekar ◽  
Sea-Fue Wang ◽  
Sriram Balasubramanian ◽  
Ashwini Anantharaman ◽  
...  
Keyword(s):  
Electrochemical Properties ◽  
Organic Dyes ◽  
Energy Requirements ◽  
Green Solvents ◽  
Reaction Media

By serving as alternatives to toxic and hazardous solvents, green solvents assist in implementing the idea of sustainability. The use of these neoeric reaction media dramatically reduces energy requirements and...

scholarly journals THE ENZYMATIC REDUCTION OF CYTOCHROME C

1940 ◽  
Vol 136 (3) ◽  
pp. 747-774 ◽  
Author(s):  
Erwin Haas ◽  
B.L. Horecker ◽  
T.R. Hogness
Keyword(s):  
Cytochrome C ◽  
Enzymatic Reduction
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