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Oxidation Of Glucose

Selective Oxidation Of Glucose To Glucuronic Acid By Cesium-promoted Gold Nanoparticle Catalyst

Selective Oxidation Of Glucose To Glucuronic Acid By Cesium-promoted Gold Nanoparticle Catalyst

Selective oxidation of glucose to glucuronic acid by cesium-promoted gold nanoparticle catalyst Author links open overlay panel RobertWojcieszakac First gold catalyzed oxidation of sugars into glucuronic acid. Selective oxidation of glucose, fructose and maltose into glucuronic acid. Cesium hydroxide as an excellent dopant for Au/CeO2 catalyst. Oxidation in the presence of added base is not selective. Gold catalysts outperform palladium and platinum catalysts for the oxidation of sugars with high activity and selectivity toward aldonic acids. The oxidation into other sugar acids, such as uronic and aldaric acids, has been scarcely investigated. Au nanoparticles supported on CeO2 using a soft chemical reduction method with hydrazine, were active for the selective oxidation of low weight carbohydrates (glucose, fructose, maltose) into glucuronic acid. The oxidation occurred in aqueous solution at low temperature using O2 as oxidant and without adding any base. The activity was improved by modifying the supported Au catalyst with cesium, while selectivity was maintained. Under these conditions, high selectivity to glucuronic acid was achieved; however, in the presence of base many by-products were obtained. The preparation of glucuronic acid in high yield using gold catalysts was never reported, which makes the catalyst developed here very interesting for liquid phase oxidation processes. Continue reading >>

1. Overview Of Glucose Oxidation

1. Overview Of Glucose Oxidation

To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video From the course by Korea Advanced Institute of Science and Technology Biochemical Principles of Energy Metabolism Biochemical Principles of Energy Metabolism Everyone knows that energy is essential for sustaining life. How can you define energy in life? Have ever thought about ways of how carbohydrates like glucose from your diet can be used for extracting energy? A scientific field that focuses on energy production and flow though living cells and organisms is called bioenergetics. Energy metabolism covers various biochemical ways of energy transformation and regulatory mechanisms of over thousands chemical reactions. Without fine control of those metabolic processes, cells and organisms cannot maintain activities linked to life. This 7 week-course will give you a clear introduction to the basic fundamentals of energy metabolism. We will first establish the concept of energy metabolism and subsequently examine biochemical steps involved in energy production from glucose oxdiation as well as glucose synthesis via photosynthesis. We will also learn about metabolic reactions related to fat as well as regulatory actions among different organs. Finally, dysregulated energy metabolism in pathological conditions such as diabetes and cancer will be discussed. Everyone knows that energy is essential for sustaining life. How can you define energy in life? Have ever thought about ways of how carbohydrates like glucose from your diet can be used for extracting energy? A scientific field that focuses on energy production and flow though living cells and organisms is called bioenergetics. Energy metabolism covers various biochemical ways of energy transformation and regula Continue reading >>

Phases Of Complete Glucose Breakdown

Phases Of Complete Glucose Breakdown

Cellular respiration involves a metabolic pathway of enzymes assisted by coenzymes The two coenzymes involved in cellular respiration, NAD+ and FAD, receive the hydrogen atoms removed from glucose. Glucose has 12 hydrogen atoms that will be pulled off one at a time and picked up by NAD+ or FAD. The complete oxidation of glucose involves four phases. 1. Glycolysis, the splitting of glucose into two 3-carbon molecules 2. The preparatory reaction, which divides each 3-carbon molecule into a 2-carbon molecule and CO2 3. The citric acid or Krebs cycle, which produces CO2, NADH, FADH2, and ATP 4. The electron transport chain also known as the electron transport system, assists in the production of the largest amount of ATP Except for glycolysis, the stages of ATP production occur in the mitochondria. The stages that occur in the mitochondrion are known as cellular respiration. The last step (the electron transport system) require the presence of oxygen. The structure of mitochondria is important for them to work properly. The cristae provide extra surface area for the proteins (enzymes) of the ETS. The Electron Transport Chain (or electron transport system) The electron transport chain is located in the cristae of the mitochondria. The members of the electron transport chain accept electrons from the hydrogen atoms carried by NADH and FADH2. As the electrons are passed down the electron transport chain, energy is released and captured for ATP production. At the end of the electron transport chain, the electrons are donated to oxygen atoms which combine with the hydrogens from NADH and FADH2 to form water.We breathe in order to have oxygen at the bottom of the ETS. Without it, cellular respiration cannot occur. The enzymes of the electron transport chain are imbedded in the c Continue reading >>

How Many Net Atp Produce From Complete Oxidation Of Glucose?

How Many Net Atp Produce From Complete Oxidation Of Glucose?

How many net ATP produce from complete oxidation of glucose? by M shahin , , - 4 years ago Explanation:2molecules ofATP- inGlycolysis( net gain ).2molecules ofATP- inKrebs Cycle.28molecules ofATP- inElectron Transport Chain.-1 NADH produces x2.5 ATP ( there are10 NADHproduced )-1 FADH2 produces x1.5 ATP ( there are2 FADH2produced ) Can't find the answers you're looking for? Ask your own questions, and get answers from specialists on Bayt.com Enter your contact details to send you the answer or log in This field must contain at least 15 characters. This field must contain 150 characters or less. Please make sure that your answer is written in the same language as the question. Thank you for answering the question. Unfortunately, the answer you are trying to submit has already been added. You can't add content on Bayt.com Specialties because your account has been blocked for violating the terms of service. You can't add content on Bayt.com Specialties because you don't have a rank yet or your email hasn't been verified. Answer should contain a minimum of 25 characters. Continue reading >>

Carbohydrate Catabolism

Carbohydrate Catabolism

Digestion is the breakdown of carbohydrates to yield an energy rich compound called ATP . The production of ATP is achieved through the oxidation of glucose molecules. In oxidation, the electrons are stripped from a glucose molecule to reduce NAD+ and FAD . NAD+ and FAD possess a high energy potential to drive the production of ATP in the electron transport chain . ATP production occurs in the mitochondria of the cell. There are two methods of producing ATP: aerobic and anaerobic . In aerobic respiration, oxygen is required. Oxygen plays a key role as it increases ATP production from 4 ATP molecules to about 30 ATP molecules. In anaerobic respiration, oxygen is not required. When oxygen is absent, the generation of ATP continues through fermentation.There are two types of fermentation: alcohol fermentation and lactic acid fermentation . There are several different types of carbohydrates : polysaccharides (e.g., starch , amylopectin , glycogen , cellulose ), monosaccharides (e.g., glucose , galactose , fructose , ribose ) and the disaccharides (e.g., sucrose , maltose , lactose ). Glucose reacts with oxygen in the following redox reaction, C6H12O6 + 6O2 6CO2 + 6H2O, Carbon dioxide and water are waste products, and the overall reaction is exothermic . The breakdown of glucose into energy in the form of molecules of ATP is therefore one of the most important biochemical pathways found in living organisms. Glycolysis , which means sugar splitting, is the initial process in the cellular respiration pathway. Glycolysis can be either an aerobic or anaerobic process. When oxygen is present, glycolysis continues along the aerobic respiration pathway. If oxygen is not present, then ATP production is restricted to anaerobic respiration . The location where glycolysis, aerobic or Continue reading >>

What Is The Complete Oxidation Of A Glucose Molecule?

What Is The Complete Oxidation Of A Glucose Molecule?

What is the Complete Oxidation of a Glucose Molecule? Kirstin Hendrickson is a writer, teacher, coach, athlete and author of the textbook "Chemistry In The World." She's been teaching and writing about health, wellness and nutrition for more than 10 years. She has a Bachelor of Science in zoology, a Bachelor of Science in psychology, a Master of Science in chemistry and a doctoral degree in bioorganic chemistry. A woman is taking a deep breath outdoors.Photo Credit: kaspiic/iStock/Getty Images Oxidation is a chemical process that, loosely defined, involves removing electrons from particular areas of a molecule. In biochemical processes, oxidation generally results in the release of energy. As such, when you "burn" glucose for energy, your cells are actually oxidizing the glucose molecule to produce the products carbon dioxide and water. The glucose molecule contains stored energy in its bonds, just as other nutrient molecules do, including starch, proteins and fats. When you consume food that contains glucose, you digest the food and absorb the glucose into your bloodstream. From there, cells take up the glucose and either store it for later use or chemically burn it to provide energy. Oxidation of glucose is analogous to burning wood in many ways: It releases chemical energy. The process of complete glucose oxidation begins with a cell splitting a glucose molecule into two molecules of pyruvate, explain Drs. Reginald Garrett and Charles Grisham in their book "Biochemistry." This takes place through a series of 10 reactions collectively called glycolysis. Splitting of glucose into pyruvate represents a partial oxidation of glucose and occurs with the release of a small amount of energy. Complete oxidation of glucose, however, requires additional reactions. The remainde Continue reading >>

Catalytic Oxidation Of Glucose On Bismuth-promoted Palladium Catalysts - Sciencedirect

Catalytic Oxidation Of Glucose On Bismuth-promoted Palladium Catalysts - Sciencedirect

Catalytic Oxidation of Glucose on Bismuth-Promoted Palladium Catalysts Author links open overlay panel BessonM. LahmerF. GallezotP. FuertesP. FlecheG. Get rights and content Water solutions of glucose (1.66 mol liter1) were oxidized with air at 313 K on palladium catalysts supported on active charcoal. High gluconate yields (99.3%) were obtained in the presence of bismuth-promoted catalysis. Bismuth was deposited via a surface redox reaction on Pd/C catalysts containing 1- to 2-nm Pd particles. A STEM-EDX study showed that bismuth atoms are selectively and homogeneously deposited on the palladium particles. The catalyst can be recycled without loss of activity and selectivity. Bismuth was not leached from the catalyst during reaction and recycling. Bismuth adatoms prevent oxygen poisoning of the palladium surface by acting as a co-catalyst in the oxidative dehydrogenation mechanism. It was determined by calorimetric measurements that oxygen should adsorb preferentially on bismuth rather than on palladium. Continue reading >>

Section 16.1oxidation Of Glucose And Fatty Acids To Co2

Section 16.1oxidation Of Glucose And Fatty Acids To Co2

The complete aerobic oxidation of glucose is coupled to the synthesis of as many as 36 molecules of ATP: Glycolysis, the initial stage of glucose metabolism, takes place in the cytosol and does not involve molecular O. It produces a small amount of ATP and the three-carbon compound pyruvate. In aerobic cells, pyruvate formed in glycolysis is transported into the mitochondria, where it is oxidized by O to CO. Via chemiosmotic coupling, the oxidation of pyruvate in the mitochondria generates the bulk of the ATP produced during the conversion of glucose to CO. In this section, we discuss the biochemical pathways that oxidize glucose and fatty acids to CO and HO; the fate of the released electrons is described in the next section. Go to: Cytosolic Enzymes Convert Glucose to Pyruvate A set of 10 enzymes catalyze the reactions, constituting the glycolytic pathway, that degrade one molecule of glucose to two molecules of pyruvate (Figure 16-3). All the metabolic intermediates between glucose and pyruvate are watersoluble phosphorylated compounds. Four molecules of ATP are formed from ADP in glycolysis (reactions 6 and 9). However, two ATP molecules are consumed during earlier steps of this pathway: the first by the addition of a phosphate residue to glucose in the reaction catalyzed by hexokinase (reaction 1), and the second by the addition of a second phosphate to fructose 6-phosphate in the reaction catalyzed by phosphofructokinase-1 (reaction 3). Thus there is a net gain of two ATP molecules. The balanced chemical equation for the conversion of glucose to pyruvate shows that four hydrogen atoms (four protons and four electrons) are also formed: (For convenience, we show pyruvate in its un-ionized form, pyruvic acid, although at physiological pH it would be largely dissociat Continue reading >>

Electricity Generation By Direct Oxidation Of Glucose In Mediatorless Microbial Fuel Cells

Electricity Generation By Direct Oxidation Of Glucose In Mediatorless Microbial Fuel Cells

Electricity generation by direct oxidation of glucose in mediatorless microbial fuel cells Nature Biotechnology volume 21, pages 12291232 (2003) Abundant energy, stored primarily in the form of carbohydrates, can be found in waste biomass from agricultural, municipal and industrial sources as well as in dedicated energy crops, such as corn and other grains 1 , 2 , 3 , 4 . Potential strategies for deriving useful forms of energy from carbohydrates include production of ethanol 4 , 5 , 6 and conversion to hydrogen 7 , 8 , 9 , 10 , but these approaches face technical and economic hurdles. An alternative strategy is direct conversion of sugars to electrical power. Existing transition metalcatalyzed fuel cells cannot be used to generate electric power from carbohydrates 11 . Alternatively, biofuel cells in which whole cells or isolated redox enzymes catalyze the oxidation of the sugar have been developed 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , but their applicability has been limited by several factors, including (i) the need to add electron-shuttling compounds that mediate electron transfer from the cell to the anode, (ii) incomplete oxidation of the sugars and (iii) lack of long-term stability of the fuel cells. Here we report on a novel microorganism, Rhodoferax ferrireducens, that can oxidize glucose to CO2 and quantitatively transfer electrons to graphite electrodes without the need for an electron-shuttling mediator. Growth is supported by energy derived from the electron transfer process itself and results in stable, long-term power production. Subscribe to Nature Biotechnology for full access: Bjerre, A.B., Olesen, A.B., Fernqvist, T., Plger, A. & Schmidt. A.S. Pretreatment of wheat straw using combined wet oxidation and alkaline hydrolysis resulting in convertible Continue reading >>

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An Error Occurred Setting Your User Cookie

An Error Occurred Setting Your User Cookie This site uses cookies to improve performance. If your browser does not accept cookies, you cannot view this site. There are many reasons why a cookie could not be set correctly. Below are the most common reasons: You have cookies disabled in your browser. You need to reset your browser to accept cookies or to ask you if you want to accept cookies. Your browser asks you whether you want to accept cookies and you declined. To accept cookies from this site, use the Back button and accept the cookie. Your browser does not support cookies. Try a different browser if you suspect this. The date on your computer is in the past. If your computer's clock shows a date before 1 Jan 1970, the browser will automatically forget the cookie. To fix this, set the correct time and date on your computer. You have installed an application that monitors or blocks cookies from being set. You must disable the application while logging in or check with your system administrator. This site uses cookies to improve performance by remembering that you are logged in when you go from page to page. To provide access without cookies would require the site to create a new session for every page you visit, which slows the system down to an unacceptable level. This site stores nothing other than an automatically generated session ID in the cookie; no other information is captured. In general, only the information that you provide, or the choices you make while visiting a web site, can be stored in a cookie. For example, the site cannot determine your email name unless you choose to type it. Allowing a website to create a cookie does not give that or any other site access to the rest of your computer, and only the site that created the cookie can read it. Continue reading >>

The Oxidation Of Glucose With Platinum On Carbon As Catalyst

The Oxidation Of Glucose With Platinum On Carbon As Catalyst

Volume 67, Issue 1 , January 1981, Pages 1-13 The oxidation of glucose with platinum on carbon as catalyst Author links open overlay panel J.M.H.Dirkx1 H.S.van der Baan Get rights and content This paper deals with the oxidation of glucose in a weakly alkaline medium with platinum on carbon as catalyst. Glucose reacts very fast with chemisorbed oxygen (PtO) to yield gluconic acid, while in an oxygen-containing atmosphere a side reaction occurs, resulting in the formation of appreciable amounts of uronic acids. Most probably, this side reaction involves molecular oxygen, resulting in the oxidation of both the primary alcohol group and the aldehyde group of glucose. In the course of an experiment a strong catalyst deactivation takes place, which can be reversed by temporarily replacing the oxygen flow by a nitrogen flow. The deactivation of the catalyst is ascribed to the formation of platinum oxide (PtO2). The formation of PtO2 and the oxidation of glucose are chemically coupled. The reactivation of the catalyst in the absence of oxygen is a reduction reaction between PtO2 and adsorbed glucose. Continue reading >>

Relationship Between Glucose Oxidation And Glucose Tolerance In Man

Relationship Between Glucose Oxidation And Glucose Tolerance In Man

Volume 31, Issue 9 , September 1982, Pages 866-870 Relationship between glucose oxidation and glucose tolerance in man Get rights and content The study was performed to determine the influence of peripheral glucose utilization on glucose tolerance. Glucose oxidation was measured in a group of 6 normal subjects by means of continuous indirect calorimetry during a 100 g oral glucose tolerance test for 3 hr, comparing the control state with experimental inhibition or stimulation of glucose oxidation. Suprabasal oxidation, corresponding to oxidation in response to the load, mainly by insulin-dependent tissue, was obtained by subtracting basal oxidation (essentially by non-insulin dependent tissues) from total oxidation. Suprabasal oxidation of glucose was inhibited by a neutral fat infusion, and stimulated by means of dichloracetate. In the control test, from the 100 g glucose administered, 18 g participated to suprabasal oxidation during the 3 hr of the test. A neutral fat infusion, started 2 hr before the glucose load and lasting throughout the test, decreased suprabasal oxidation to 7.5 g, i.e. to 42% of the control value. With the fat infusion, a larger fraction of the energy consumption was shown to originate from lipid oxidation (37% versus 25% in controls, p < 0.05) at the expense of carbohydrate (CHO) oxidation (44% versus 60% in controls, p < 0.05). However, these major changes in peripheral glucose oxidation were accompanied by only a moderate decrease in glucose tolerance. Dichloracetate administered prior to the test increased suprabasal oxidation to 25 g glucose oxidized in the 3 hours following the glucose load, i.e. an increment of 39% above the control value. A larger fraction of energy consumption was derived from carbohydrates (77% versus 60% in controls, Continue reading >>

Box13-1

Box13-1

Entropy: The Advantages of Being Disorganized The term entropy, which literally means "a change within," was first used in 1851 by Rudolf Clausius, one of the promulgators of the second law. A rigorous quantitative defmition of entropy involves statistical and probability considerations. However, its nature can be illustrated qualitatively by three simple examples, each of which shows one aspect of entropy. The key descriptors of entropy are randomness or disorder, manifested in different ways. Case 1: The Teakettle and the Randomization of Heat We know that steam generated from boiling water can do useful work. But suppose we turn off the burner under a teakettle full of water at 100 C (the "system") in the kitchen (the "surroundings") and allow it to cool. As it cools, no work will be done, but heat will pass from the teakettle to the surroundings, raising the temperature of the surroundings (the kitchen) by an infmitesimally small amount until complete equilibrium is attained. At this point all parts of the teakettle and the kitchen will be at precisely the same temperature. The free energy that was once concentrated in the teakettle of hot water at 100 C, potentially capable of doing work, has disappeared. Its equivalent in heat energy is still present in the teakettle + kitchen (i.e., the "universe") but has become completely randomized throughout. This energy is no longer available to do work because there is no temperature differential within the kitchen. Moreover, the increase in entropy of the kitchen (the surroundings) is irreversible. We know from everyday experience that heat will never spontaneously pass back from the kitchen into the teakettle to raise the temperature of the water to 100 C again. Entropy is a state or condition not only of energy but also Continue reading >>

Oxidation Of Glucose

Oxidation Of Glucose

A living organism requires energy simply to survive as an organized structure, letalone to perform any useful functions. In this section we explore the chemistry of themajor source of the energy used by animals, the oxidation of glucose. Biochemical, or living, systems require sources of energy. The fundamental source ofenergy for them is light, whose source is the sun. A small fraction (for sugar cane, 8% ofincident light; for corn, 1 - 2%) of this light can be used by plants, throughphotosynthesis, to obtain compounds from carbon dioxide and water. The sugar glucose,whose molecular formula is C6H12O6, is formed by theoverall reaction Under standard conditions of 25o C and one atmosphere pressure, the standardfree energy change DGo of this reaction is +2870 kJ/mole. To make thisnon-spontaneous process go, 2870 kJ/mole must be supplied by energy from elsewhere, inthis case light. The synthesis of glucose may be taken as typical of the production ofcarbohydrates, or even of organic compounds generally, in plants. Animals, such as human beings, are not capable of photosynthesis and so they derivetheir energy by running reactions such as this backwards, degrading the glucose to,ultimately, carbon dioxide and water. The overall reaction of glucose oxidation is thereverse of the overall reaction for its formation. Fot he reverse reaction the standardfree energy change DGo must then be -2870 kJ/mole. The basic problem in animal metabolism is that 2870 kJ is too much energy to use in onelump; it has to be broken down into smaller units. This can be seen if we consider therelationship DGo = -RT ln K; DGo = -1.363 log K, at 25oC.The effect is clearer in tabular form. Table: Equilibrium Constants and Free Energy Changes Consider a somewhat typical biochemical reaction carried ou Continue reading >>

Cellular Respiration

Cellular Respiration

Typical eukaryotic cell Cellular respiration is a set of metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products.[1] The reactions involved in respiration are catabolic reactions, which break large molecules into smaller ones, releasing energy in the process, as weak so-called "high-energy" bonds are replaced by stronger bonds in the products. Respiration is one of the key ways a cell releases chemical energy to fuel cellular activity. Cellular respiration is considered an exothermic redox reaction which releases heat. The overall reaction occurs in a series of biochemical steps, most of which are redox reactions themselves. Although technically, cellular respiration is a combustion reaction, it clearly does not resemble one when it occurs in a living cell because of the slow release of energy from the series of reactions. Nutrients that are commonly used by animal and plant cells in respiration include sugar, amino acids and fatty acids, and the most common oxidizing agent (electron acceptor) is molecular oxygen (O2). The chemical energy stored in ATP (its third phosphate group is weakly bonded to the rest of the molecule and is cheaply broken allowing stronger bonds to form, thereby transferring energy for use by the cell) can then be used to drive processes requiring energy, including biosynthesis, locomotion or transportation of molecules across cell membranes. Aerobic respiration Aerobic respiration (red arrows) is the main means by which both fungi and animals utilize chemical energy in the form of organic compounds that were previously created through photosynthesis (green arrow). Aerobic respiration requires oxygen (O2) in order to Continue reading >>

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