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What Test Could Be Used To Differentiate Between Fructose And Glucose

Lab Review 1 | Biochemistry Is A Good Thing

Lab Review 1 | Biochemistry Is A Good Thing

Hello there again my Biochem peeps. Today I want to do a bit of review of our lab session and highlight the important details that may be helpful for our quiz next week. Therefore, I will try and breakdown each test performed and details the expected results and the reasoning behind said results. This will be done in three parts since our lab consisted of testing for Carbohydrates, Lipids and Amino acids/proteins. Below is the first portion of the Lab that contained most of the Carbohydrate tests. I hope that this information is a bit helpful. Not specific to carbohydrates. However, a negative test result may rule out the presence of carbohydrates. The reaction: Carbohydrates, specifically monosaccharides are dehydrated in the presence of concentrated sulphuric acid to form an aldehyde known as furfural (pentoses) or hydroxymethyl furfural (hexoses) derivatives. Polysaccharides and disaccharides are converted to monosaccharides via hydrolysis of the glycosidic bonds. The monosaccharide/furfural derivatives then react with 1-naphthol in Molisch reagent via a condensation reaction to form a purple coloured compound. The result: The purple-coloured compound appears as a ring layer at the interface between the sulphuric acid and test solution. The sulphuric acid is denser than the test solution and therefore the reaction will occur at the junction where both substances meet. Lab results: Glucose, maltose, arabinose and starch will all display the purple ring compound at the interface of the acid and solution. -Generalized test that cannot distinguish carbohydrates and further testing must be undertaken to identify the carbohydrate. Test for the presence of a reducing sugar. All monosaccharides are reducing sugars as well as some disaccharides and polysaccharides as long as Continue reading >>

Benedict's Test- Principle, Composition, Preparation, Procedure And Result Interpretation

Benedict's Test- Principle, Composition, Preparation, Procedure And Result Interpretation

Benedicts Test- Principle, Composition, Preparation, Procedure and Result Interpretation 4.3/5 (602) Benedicts Test- Principle, Composition, Preparation, Procedure and Result Interpretation Benedicts Test is used to test for simple carbohydrates.The Benedicts test identifies reducing sugars (monosaccharides and some disaccharides), which have free ketone or aldehyde functional groups.Benedicts solution can be used to test for the presence ofglucose in urine. Some sugars such as glucose are called reducing sugars because they are capable of transferring hydrogens (electrons) to other compounds, a process called reduction. When reducing sugars are mixed with Benedicts reagent and heated, a reduction reaction causes the Benedicts reagent to change color. The color varies from green to dark red (brick) or rusty-brown, depending on the amount of and type of sugar. Benedicts quantitative reagent contains potassium thiocyanate and is used to determine how much reducing sugar is present. This solution forms a copper thiocyanate precipitate which is white and can be used in a titration. The titration should be repeated with 1% glucose solution instead of the sample for calibration When Benedicts solution and simple carbohydrates are heated, the solution changes to orange red/ brick red. This reaction is caused by the reducing property of simple carbohydrates. The copper (II) ions in the Benedicts solution are reduced to Copper (I) ions, which causes the color change. The red copper(I) oxide formed is insoluble in water and is precipitated out of solution. This accounts for the precipitate formed.As the concentration of reducing sugar increases, the nearer the final colour is to brick-red and the greater the precipitate formed.Sometimes a brick red solid, copper oxide, precipita Continue reading >>

Distinguish Between Glucose And Fructose Using Chemicaltests - 8550557 | Meritnation.com

Distinguish Between Glucose And Fructose Using Chemicaltests - 8550557 | Meritnation.com

Glucose and fructose can be distinguished by a number of chemical tests such as: Seliwanoffstest-Itis a chemical test that distinguishes betweenaldose(glucose) andketose(fructose) sugars. This test is based on the fact that, when heated, ketoses are more rapidly dehydrated thanaldoses. Acid hydrolysis of sugars is followed by adding resorcinol and concentratedHCl. The dehydratedketosethen reacts with the resorcinolto produce a deep cherry red colour.Aldosesmay react slowly to produce a faint pink colour. Furfuraltest- The sugar is treated with an alcoholic solution ofalpha-naphtholandconcentratedHCland the mixture is boiled. An immediate violet colour is produced with fructose. Whereas, the colour appears after a few minutes with glucose. AmmoniumMolybdatetest- Freshly prepared 4% aqueous solution of ammoniummolybdateis added to an equal volume of 1% solution of sugar in a boiling tube, followed by 4-5 drops of glacial acetic acid. As the boiling tube is heated, fructose gives a greenish-blue coloration within 3-4 minutes whereas, glucose gives only a very faint coloration after 10 minutes. Continue reading >>

What Test Could Be Use To Differentiate Lactose And Glucose?

What Test Could Be Use To Differentiate Lactose And Glucose?

What test could be used to differentiate between sucrose and maltose? What test could be used to differentiate between sucrose and maltose? Would you like to merge this question into it? already exists as an alternate of this question. Would you like to make it the primary and merge this question into it? Answers.com is making the world better one answer at a time. Benedict's test - from a clear blue solution to a cloudy rust/brown solution. Maltose and Lactose are "Reducing Sugar's" in solution with Benedict's Reagent, while sucrose is not. Sucrose is made by the glosidic linkage between glucose and fructose whereas maltose is made by the glycosidic linkage between two glucose molecules. the first figure is maltose and second is sucrose(courtesy google images) (MORE) What test could be use to differentiate lactose and glucose? take solution of substance in one test tube; in another test tube take acetic acid, water and phenyl hydrazine in 1:2:1 ratio. mix the solution of both test tubes and heat at water bath. if precipitates form immediately--> its glucose; if precipitates form after long heating--> its lactose. (MORE) Continue reading >>

What Carbohydrate Test Would Distinguish Between Fructose And Glucose?

What Carbohydrate Test Would Distinguish Between Fructose And Glucose?

What carbohydrate test would distinguish between fructose and glucose? Name and describe the test and why should it be used. Are you sure you want to delete this answer? Best Answer: Seliwanoffs test (resorcinol + HCl or H2SO4) distinguishes fructose from glucose. A positive test for fructose is a red precipitate. You might think that Fehling's solution would distinguish an aldose from a ketose, but it doesn't work because under the conditions, fructose can rearrange to glucose, which is reduced. I think this question violates the Community Guidelines Chat or rant, adult content, spam, insulting other members, show more I think this question violates the Terms of Service Harm to minors, violence or threats, harassment or privacy invasion, impersonation or misrepresentation, fraud or phishing, show more If you believe your intellectual property has been infringed and would like to file a complaint, please see our Copyright/IP Policy I think this answer violates the Community Guidelines Chat or rant, adult content, spam, insulting other members, show more I think this answer violates the Terms of Service Harm to minors, violence or threats, harassment or privacy invasion, impersonation or misrepresentation, fraud or phishing, show more If you believe your intellectual property has been infringed and would like to file a complaint, please see our Copyright/IP Policy I think this comment violates the Community Guidelines Chat or rant, adult content, spam, insulting other members, show more I think this comment violates the Terms of Service Harm to minors, violence or threats, harassment or privacy invasion, impersonation or misrepresentation, fraud or phishing, show more If you believe your intellectual property has been infringed and would like to file a complaint, please Continue reading >>

Carbohydrates

Carbohydrates

Carbohydrates (also called saccharides) are molecular compounds made from just three elements: carbon, hydrogen and oxygen. Monosaccharides (e.g. glucose) and disaccharides (e.g. sucrose) are relatively small molecules. They are often called sugars. Other carbohydrate molecules are very large (polysaccharides such as starch and cellulose). Carbohydrates are: a source of energy for the body e.g. glucose and a store of energy, e.g. starch in plants building blocks for polysaccharides (giant carbohydrates), e.g. cellulose in plants and glycogen in the human body components of other molecules eg DNA, RNA, glycolipids, glycoproteins, ATP Monosaccharides Monosaccharides are the simplest carbohydrates and are often called single sugars. They are the building blocks from which all bigger carbohydrates are made. Monosaccharides have the general molecular formula (CH2O)n, where n can be 3, 5 or 6. They can be classified according to the number of carbon atoms in a molecule: n = 3 trioses, e.g. glyceraldehyde n = 5 pentoses, e.g. ribose and deoxyribose ('pent' indicates 5) n = 6 hexoses, e.g. fructose, glucose and galactose ('hex' indicates 6) There is more than one molecule with the molecular formula C5H10O5 and more than one with the molecular formula C6H12O6. Molecules that have the same molecular formula but different structural formulae are called structural isomers. Glyceraldehyde's molecular formula is C3H6O3. Its structural formula shows it contains an aldehyde group (-CHO) and two hydroxyl groups (-OH). The presence of an aldehyde group means that glyceraldehyde can also be classified as an aldose. It is a reducing sugar and gives a positive test with Benedict's reagent. CH2OHCH(OH)CHO is oxidised by Benedict's reagent to CH2OHCH(OH)COOH; the aldehyde group is oxidised to Continue reading >>

Qualitative Analysis Of Carbohydrates (theory) : Biochemistry Virtual Lab I : Biotechnology And Biomedical Engineering : Amrita Vishwa Vidyapeetham Virtual Lab

Qualitative Analysis Of Carbohydrates (theory) : Biochemistry Virtual Lab I : Biotechnology And Biomedical Engineering : Amrita Vishwa Vidyapeetham Virtual Lab

This forms the reduction test of carbohydrates. Fehlings solution contains blue alkaline cupric hydroxide solution, heated with reducing sugars gets reduced to yellow or red cuprous oxide and is precipitated. Hence, formation of the yellow or brownish-red colored precipitate helps in the detection of reducing sugars in the test solution. As in Fehlings test, free aldehyde or keto group in the reducing sugars reduce cupric hydroxide in alkaline medium to red colored cuprous oxide. Depending on the concentration of sugars, yellow to green color is developed . All monosaccharides are reducing sugars as they all have a free reactive carbonyl group. Some disaccharides, like maltose, have exposed carbonyl groups and are also reducing sugars, but less reactive than monosaccharides Barfoed's test is used to detect the presence of monosaccharide (reducing) sugars in solution. Barfoed's reagent, a mixture of ethanoic (acetic) acid and copper(II) acetate, is combined with the test solution and boiled. A red copper(II) oxide precipitate is formed will indicates the presence of reducing sugar. The reaction will be negative in the presence of disaccharide sugars because they are weaker reducing agents. This test is specific for monosaccharides . Due to the weakly acidic nature of Barfoed's reagent, it is reduced only by monosaccharides. It is a color reaction specific for ketoses. When conce: HCl is added. ketoses undergo dehydration to yield furfural derivatives more rapidly than aldoses. These derivatives form complexes with resorcinol to yield deep red color. The test reagent causes the dehydration of ketohexoses to form 5-hydroxymethylfurfural. 5-hydroxymethylfurfural reacts with resorcinol present in the test reagent to produce a red product within two minutes (reaction not sho Continue reading >>

Bio Lab Exam Flashcards | Quizlet

Bio Lab Exam Flashcards | Quizlet

carbohydrates are also found in the form of "many sugars" aka a polysaccharide composed only of glucose subunits, especially abundant in plants the plants way of storing the glucose it makes during photosynthesis food reserves that the plant has stored for its own use the starch of potatoes and root vegetables for example would be used the next spring for the plant's renewed growth after the winter die-back. plants that come up year after year such as tulips perennial plants (have some kind of food storage for overwintering) beans (die at the end of the growing season) so the seeds are stocked with starch to use when they have a chance to germinate the next spring glycogen (another form of polysaccharide) although starch and glycogen are both composed of glucose subunits, the glucose molecules are bonded together in different ways, so these polysaccharides are not identical glucose subunits are bonded together a third way in the polysaccharide while starch and glycogen are metabolized for 1), cellulose (the most abundant carbohydrate in the world) is a 2) 2) a structural molecule that is designed not to be metabolized 2) and its the primary component of dietary fiber for most animals 1) is completely indigestible, those that can digest it such as 2) do so only with the assistance of organisms such as 3) most disaccharides and polysaccharides can be broken down into their component monosaccharides by a process called hydrolysis is accomplished in organisms by seeds (if the seed's food resource is starch, it must be able to convert starch to glucose) seed takes up water and begins to germinate germination of barley seeds is part of the process of in the breakdown of starch, disaccharide 1) are formed before the final product, 2), is obtained the process of germinating th Continue reading >>

What Is The Difference Between Sucrose, Glucose & Fructose?

What Is The Difference Between Sucrose, Glucose & Fructose?

Sucrose, glucose and fructose are important carbohydrates, commonly referred to as simple sugars. Sugar is found naturally in whole foods and is often added to processed foods to sweeten them and increase flavor. Your tongue can't quite distinguish between these sugars, but your body can tell the difference. They all provide the same amount of energy per gram, but are processed and used differently throughout the body. Structure Simple carbohydrates are classified as either monosaccharides or disaccharides. Monosaccharides are the simplest, most basic units of carbohydrates and are made up of only one sugar unit. Glucose and fructose are monosaccharides and are the building blocks of sucrose, a disaccharide. Thus, disaccharides are just a pair of linked sugar molecules. They are formed when two monosaccharides are joined together and a molecule of water is removed -- a dehydration reaction. The most important monosaccharide is glucose, the body’s preferred energy source. Glucose is also called blood sugar, as it circulates in the blood, and relies on the enzymes glucokinase or hexokinase to initiate metabolism. Your body processes most carbohydrates you eat into glucose, either to be used immediately for energy or to be stored in muscle cells or the liver as glycogen for later use. Unlike fructose, insulin is secreted primarily in response to elevated blood concentrations of glucose, and insulin facilitates the entry of glucose into cells. Fructose is a sugar found naturally in many fruits and vegetables, and added to various beverages such as soda and fruit-flavored drinks. However, it is very different from other sugars because it has a different metabolic pathway and is not the preferred energy source for muscles or the brain. Fructose is only metabolized in the li Continue reading >>

How To Test For Simple Sugars

How To Test For Simple Sugars

Simple sugars, also referred to as monosaccharides, are the basic unit of carbohydrates. Unlike sucrose, which is made of both a glucose and fructose sugar molecule, a simple sugar is either glucose or fructose respectively. Complex sugars, or polysaccharides, are present in foods like vegetables and whole grains. You can test for these simple sugars in your foods by using Benedict’s reagent, a solution made of copper sulfate and sodium hydroxide. You can purchase this solution in a drug store as it used to indicate the presence of sugar in the urine of diabetics. Video of the Day Turn on your hot plate to medium heat and place your beaker filled with 100 mL of water on it. Bring it to a boil. Pour 4 mL of your food sample in a test tube if it is liquid based. If you are testing a solid food, you can use a food processor to puree it by adding a small amount of water or crush the item into a powder using a mortar and pestle. Add water to the powder and pour it in the test tube. Add approximately 1 mL of Benedict’s solution to the test tube using a dropper. Slowly swirl the test tube counterclockwise to distribute the reagent evenly. Place your test tube into the beaker until you note a color change -- this process usually takes five minutes. Examine the color change, if it is present. Benedict’s reagent has a color change gradient from blue, meaning no simple sugars are present, to green, yellow, orange, red and brown. The color sequence indicates the increasing concentration of the simple sugar, with green being the lowest and brown being the highest. Benedict’s reagent Beaker Test tubes and holder Graduated cyclinder Food samples Food processor Water Hot plate Mortar and pestle Dropper Continue reading >>

Seliwanoff's Test - Wikipedia

Seliwanoff's Test - Wikipedia

An example of a positive Seliwanoffs test Seliwanoffs test is a chemical test which distinguishes between aldose and ketose sugars . Ketoses are distinguished from aldoses via their ketone / aldehyde functionality. If the sugar contains a ketone group, it is a ketose. If a sugar contains an aldehyde group, it is an aldose. This test relies on the principle that, when heated, ketoses are more rapidly dehydrated than aldoses. It is named after Theodor Seliwanoff , the chemist that devised the test. When added to a solution containing ketoses, a red color is formed rapidly indicating a positive test. When added to a solution containing aldoses, a slower forming light pink is observed instead. The reagents consist of resorcinol and concentrated hydrochloric acid : The acid hydrolysis of polysaccharide and oligosaccharide ketoses yields simpler sugars followed by furfural . [1] The dehydrated ketose then reacts with two equivalents of resorcinol in a series of condensation reactions to produce a molecule with a deep cherry red color. Aldoses may react slightly to produce a faint pink color. Fructose and sucrose are two common sugars which give a positive test. Sucrose gives a positive test as it is a disaccharide consisting of fructose and glucose. ^ Abramoff, Peter; Thomson, Robert (1966). An experimental approach to biology. WH Freeman & Company, San Francisco. p. 47. Seliwanoff, Theodor (1887). "Notiz ber eine Fruchtzuckerreaction". Berichte der deutschen chemischen Gesellschaft. 20: 181. doi : 10.1002/cber.18870200144 . Continue reading >>

Difference Between Glucose And Fructose

Difference Between Glucose And Fructose

Categorized under Science | Difference Between Glucose and Fructose While not everyone would classify themselves as sweet tooth, there are few people who would gladly give up all sugar from their diet. Sugar can take many forms but the most common are sucrose, glucose, and fructose. If one is searching for the lowest common denominator, there should then just be glucose and fructose because these two monosaccharides are the building blocks of sucrose. There are many similarities between glucose and fructose. They are both simple sugars, and are monosaccharides. Simple sugars contain only one type of carbohydrate as opposed to two like the disaccharide sucrose. The chemical formula for glucose and fructose are also the same: C6(H2O)6. Once they have entered the body, both sugars eventually make their way to the liver to be metabolized. Most processed and natural foods out there contain a combination of fructose and glucose. Even foods that you would expect to be nearly all fructose, such as high fructose corn syrup, actually have a 55%-45% composition in favor of fructose. There are a few key ways in which these two sugars differ though. While their chemical formula is the same, the molecules of glucose and fructose are laid out in different formations. They both start out by making a hexagon with their six carbon atoms. Each carbon is bound to a water molecule . Glucose is an aldohexose. Its carbon is attached to a hydrogen atom by a single bond and an oxygen atom by a double bond. Fructose is a ketohexose. Its carbon is attached only to an oxygen atom by a single bond. As aforementioned, both sugars end up in the liver. However, Glucose is eaten, absorbed into the blood stream, and makes it way to the liver where it is broken down to supply energy to the entire body. Continue reading >>

Lab 1

Lab 1

Most of the chemical compounds presentin living organisms contain skeletons of covalently bonded carbon atoms(C-C-C-C). These compounds are known as organic compounds, because mostof these are either present in, or produced by living things. Organic compoundsare the major components of cells and tissues. They provide energy forlife processes, participate in and regulate metabolic reactions, and transmitinformation. Organic macromolecules in living organisms can be classifiedas either carbohydrates, proteins, lipids, or nucleic acids,among others. These macromolecules are always made of smaller subunits.The subunits of macromolecules are held together with covalent bonds, andhave different structures and properties. For example, lipids made of fattyacids have many C-H bonds and relatively little oxygen, while proteinsmade of amino acids have amino groups (-NH2) and carboxyl (-COOH)groups. These characteristic groups impart different chemical propertiesto macromolecules--for example, monosaccharides such as glucose are polarand soluble in water, while lipids are nonpolar and insoluble in water. Carbohydrates are compounds that containcarbon, hydrogen and oxygen. Carbohydrates include a variety of compounds,such as sugars, starches, and celluloses. While sugars and starches serveas energy sources for cells; celluloses are structural components of thewalls that surround plant cells. The term carbohydrate literally means"hydrated (H20) carbon" Carbohydrates may contain one sugarmolecule (monosaccharides), two sugar molecules (disaccharides), or manysugar units (polysaccharides). In this lab, we will be concerned with thenature and activities of the carbohydrates and with their structure. Note:structure dictates how the carbohydrate will react under certain conditions. Since Continue reading >>

Lab Review

Lab Review

These are complex, carbon-containing molecules associated with living organisms. Most also contain hydrogen and oxygen. There are five major types: carbohydrates, lipids, proteins, nucleic acids, and vitamins. We covered the first three types in lab. A review of our carbohydrate test data is provided on this page. Click the molecule types above to link to the associated review material. Benedict's Reagent: A Test for Reducing Sugars Carbohydrates are divided into two groups based on the complexity of their structure. Simple carbohydrates can form either a single ring structure (monosaccharides) or a double ring structure (disaccharides -- formed when a pair of monosaccharides bond). Simple carbohydrates include familiar sugars such the monosaccharides glucose (the basic fuel of cells) and fructose (found in fruits). Common disaccharides include sucrose (table sugar) and lactose (the sugar in milk). Complex carbohydrates (polysaccharides) are chains of many bonded simple carbohydrates, and are often used for energy storage. These include starch, cellulose, and glycogen. One test for the presence of many simple carbohydrates is to use Benedict's reagent. It turns from turquoise to yellow or orange when it reacts with reducing sugars. These are simple carbohydrates with unbound aldehyde or ketone groups. In lab, we used Benedict's reagent to test for one particular reducing sugar: glucose. Benedict's reagent starts out aqua-blue. As it is heated in the presence of reducing sugars, it turns yellow to orange. The "hotter" the final color of the reagent, the higher the concentration of reducing sugar. In general, blue to blue-green or yellow-green is negative, yellowish to bright yellow is a moderate positive, and bright orange is a very strong positive. (See below). 2: Bene Continue reading >>

Sugars: The Difference Between Fructose, Glucose And Sucrose

Sugars: The Difference Between Fructose, Glucose And Sucrose

29/06/2016 7:43 AM AEST | Updated 15/07/2016 12:56 PM AEST Sugars: The Difference Between Fructose, Glucose And Sucrose We're not just confused, we're also misinformed. "Fructose is the worst for you." "No way, sucrose is the devil." "I don't eat any sugar." Sugar is confusing. While some people only use certain types of sugars, others dismiss them completely. But is this necessary, or even grounded? To help settle the confusion, we spoke to Alan Barclay -- accredited practising dietitian, spokesperson for the Dietitians Association of Australia and Chief Scientific Officer at the Glycemic Index Foundation . "All the sugars are used as a source of fuel, but there are subtle differences in the way they are digested and absorbed," Barclay said. "In foods in Australia, the most common sugars are monosaccharides (glucose, fructose and galactose), but mostly these are occurring as disaccharides (which are sucrose, lactose and maltose)." Monosaccharides and disaccharides are two kinds of simple sugars, which are a form of carbohydrate. Oligosaccharides and polysaccharides, on the other hand, contain more sugar combinations and are known as complex carbohydrates -- for example, whole grain breads, brown rice and sweet potatoes. Monosaccharides require the least effort by the body to break down, meaning they are available for energy more quickly than disaccharides. "Monosaccharides don't require any digestion and can be absorbed into the mouth," Barclay said. "The problem there is they can cause dental caries which is one of the primary reasons why we need to be careful of how much added sugar we're consuming." Glucose -- the body's main source of energy and is found in fruit such as pasta, whole grain bread, legumes and a range of vegetables. Fructose -- this 'fruit sugar' fo Continue reading >>

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