Chemical Tests for Biomolecules

chemical studys for BiomoleculesKaneshanathan KumaraguruContents (jump to) submissionObjectiveMaterialsMethodologyResultsDiscussionConclusionReferencesIntroductionA macromolecule is a molecule of high comparative molecular mass, the structure of which essentially comprises the multiple repetitions of wholes derived, actually or conceptually, from molecules of low relative molecular mass (Jenkins et al., 1996, p.2289). Carbohydrates ar made of monosaccharoses, which typically consist 5 or 6 light speed straight saturated chain (Bochkov, Zaikov and Afanasiev, 1991, p.2). Proteins are made up of atomic number 53 or more polypeptides which consist of bonds of amino supermans connected by peptide bonds (Walsh, cc4, p.2).ObjectiveTo separate the macromolecules ( saccharides and proteins) by apply various chemical assays.MaterialsSamples Glucose, milk sugar, fructose, amylum, sucrose, tyrosin, tryptophan and egg albumin.Reagents Molishs reagent, iodine dissolving agent , benedicts stem, barfoeds reagent, seliwanoffs reagent, ninhydrin issue and millons reagent.Other chemicals punishing H2SO4, AgNO3, dilute NaOH, dilute NH4OH, concentrated HNO3, NaNO2/dilute HCl and sulpanilic irate.Equipments Bunsen burner, pipett, beakers and prove r give the axeers.Methodology sorts for shekelss (glucose, fructose, lactose, sucrose and starch).Molischs shield development a communicate pipet, 1ml of each clams settlement was pou inflammation into louver assay pipings. past hardly a(prenominal) drops of Molischs reagent was added into each examen subway use a tape transport pipette and mixed fountainhead. and so 2ml of concentrated H2SO4 was added down the positionings of the render pipes. one renderUsing a transfer pipette, 1ml of each kale resoluteness was pou rubor into five footrace pipages. and then(prenominal) 3 drops of diluted I2 was added into each mental interrogationing tube apply a transfer pipette.Benadicts shewU sing a transfer pipette, 5ml of Benadicts consequence was pou vehement into five study tubes. Then 1ml of each carbohydrate solution was added into each try out tube exploitation a transfer pipette and was mixed well. Test tubes were thence heat in a wet vat for 3 minutes.Barfoerds tasteUsing a transfer pipette, 1ml of each carbohydrate solution was pou bolshy into five footrace tubes. Then 5ml of Barfoerds solution was added into each judge tube using a transfer pipette and was mixed well. Test tubes were then heated in a piddle system can for 3-4 minutes.Seliwanoffs renderUsing a transfer pipette, 5ml of Seliwanoffs reagent was pou chromatic into five mental leaven tubes. Then 5-6 drops of each carbohydrate solution was added into each establish tube using a transfer pipette and was mixed. Test tubes were then heated in a weewee bath for exactly 30 seconds.Tollens testUsing a transfer pipette, 1ml of AgNO3 was poured into five test tubes. Then using a transfer pi pette, dilute NaOH was added until a slight precipitous was organize. Then dilute NH4OH was added until the headlong just dissolved. 1ml of each carbohydrate solution was then added into each test tube using a transfer pipette. Test tubes were then heated in a water bath for 5 minutes.Tests for amino acidulatedulouss (tyrosine and tryptophan) and protein (egg albumin).Ninhydrin testUsing a transfer pipette, 0.5ml of 0.02% amino acid solutions and protein was poured into cardinal test tubes. Then 1ml of Ninhydrin solution was added into each test tube using a transfer pipette and was heated in a water bath for 3-4 minutes.Xanthoproteic testUsing a transfer pipette, 2ml of 0.02% amino acid solutions and protein was poured into three test tubes. Then 2ml of concentrated HNO3 was added into each test tube using a transfer pipette and was heated in a water bath for 1-2 minutes.Millons testUsing a transfer pipette, 2ml of 0.02% amino acid solutions and protein was poured into three test tubes. Then 3-4 drops of millons reagent was added into each test tube using a transfer pipette and was heated in a water bath for 3-4 minutes.Paulys testUsing a transfer pipette, 1ml of 0.02% amino acid solutions and protein was poured into three test tubes. Then 1ml of sulphanilic acid was added into each test tube using a transfer pipette. 1ml of dilute HCl was then added into three separate test tubes. each six test tubes were unplowed in ice bath for 3 minutes. Then the amino acids / protein solutions were mixed with 1ml of dilute HCl in the test tubes and were kept in the ice bath again. Few drops of NaOH were then added to the test tubes in the ice bath.ResultsFor carbohydratesTestCompounds noticeInferenceMolischs test amylum strawman of gallant coloration crime syndicateThe coalesce is a carbohydrateGlucosebea lot of purple garble ringThe immix is a carbohydratefruit sugar comportment of purple emblazon ringThe miscellanea is a carbohydrate milk ice lolly car riage of purple contort ringThe compound is a carbohydrate sucrose presence of purple food color ringThe compound is a carbohydrate ace testStarch front man of bluish black labyrinthineThe compound is a polysaccharideGlucoseabsence seizure of blue-black ByzantineThe compound is non a polysaccharideFructose absence of blue-black complexThe compound is not a polysaccharideLactoseabsence seizure of blue-black complexThe compound is not a polysaccharide sucroseAbsence of blue-black complexThe compound is not a polysaccharideBenadicts testStarchAbsence of brick-red coloration precipitateThe compound is a non- minify sugarGlucosePresence of brick-red food colorise precipitateThe compound is a cut back sugarFructosePresence of brick-red warp precipitateThe compound is a decrease sugarLactosePresence of brick-red saturation precipitateThe compound is a reducing sugarSucroseAbsence of brick-red coloring precipitateThe compound is a non- reducing sugarBarfoerds testStarchAbsenc e of red colour precipitateThe compound is not a monosaccharoseGlucosePresence of red colour precipitateThe compound is a monosaccharoseFructosePresence of red colour precipitateThe compound is a monosaccharideLactoseAbsence of red colour precipitateThe compound is not a monosaccharideSucroseAbsence of red colour precipitateThe compound is not a monosaccharideSeliwanoffs testStarchAbsence of red colour complexThe compound contains an aldehyde aggroupGlucoseAbsence of red colour complexThe compound contains an aldehyde groupFructosePresence of red colour complexThe compound contains a ketone groupLactoseAbsence of red colour complexThe compound contains an aldehyde groupSucrosePresence of red colour complexThe compound contains a ketone groupTollens testStarchAbsence of silver mirrorThe compound is a non- reducing sugarGlucosePresence of silver mirrorThe compound is a reducing sugarFructosePresence of silver mirrorThe compound is a non- reducing sugarLactosePresence of silver mir rorThe compound is a reducing sugarSucroseAbsence of silver mirrorThe compound is a non- reducing sugarFor amino acids and proteinTestCompoundsObservationInferenceNinhydrin test testis albuminAbsence of purple colour complexThe compound is not an amino acidTryptophanPresence of purple colour complexThe compound is an amino acidTyrosinPresence of purple colour complexThe compound is an amino acidXanthoproteic testEgg albuminAbsence of yellow colour complexThe compound is a proteinTryptophanPresence of bright yellow colour complexThe compound is an amino acidTyrosinPresence of pale yellow colour complexThe compound is an amino acidMillons testEgg albuminAbsence of pink colour precipitateTryptophanAbsence of pink colour precipitatePresence of tyrosinTyrosinPresence of pink colour precipitatePaulys testEgg albuminAbsence of red azo discolorTryptophanPresence of red azo spotPresence of tryptophan/ tyrosin/ histodineTyrosinPresence of red azo dye identification number 1 Molischs test a ccount 2 one test manikin 3 Iodine testPresence of purple colour ring Presence of blue-black complex Absence of blue-black complex get in 4 Benedicts test Figure 5 Benedicts test Figure 6 Barfoerds testAbsence of brick red ppt. Presence of brick red ppt. Absence of red ppt.Figure 7 Barfoerds test Figure 8 Seliwanoffs test Figure 9 Tollens testPresence of red ppt. Presence of red colour complex Presence of silver mirrorFigure 10 Ninhydrin test Figure 11 Xanthoproteic test Figure 12 Millons testPresence of purple colour complex Presence of yellow colour complex Presence of pink colour ppt.Figure 13 Paulys testPresence of red azo dyeDiscussionThe principles of each testIn molischs test, concentrated sulphuric acid is used to dehydrate the carbohydrates to shit 5-hydroxymethylfurfural, which reacts with the naphthol to give a purple import (Pavia, 2005, p.446).In iodine test, a blue colour is practiceed when the iodine is absorbed into the open spaces of amylose molecules in starch (Pavia, 2005. p.451).In benedicts test, the sugar (reducing sugar) gets oxidized and reduces Cu2+ endow in the reagent (Raymond, 2010, p.344).Barfoerds test is a test unique for monosaccharide, where cupric hydroxide is reduced in acidic medium to give red colour cuprous oxide (Nigam and Ayyagari, 2008, p.25).In seliwanoffs test, the ketoses are dehydrated to form furfural derivatives which then centre with resorcinol to give a red colour complex (Nigam and Ayyagari, 2008, p.27).In tollens test, silver ammonium salt oxidizes the aldehyde to give glucuronide ammonium salt and metallike silver, which gives the silver mirror effect (Brito-Arias, 2007, p.5).In Ninhydrin test, free amino acid radical reacts with ninhydrin to give a blue-violet complex (Malhotra, 2003, p.23).In xanthoproteic test, benzene ring is nitrated with nitric acid which produces a yellow compound (Sim et al., 2008, p.611).In Millons test, hydroxybenzene radical of phenolic amino acids (tyrosine) react with mil lons reagent to form a red colour complex (Nigam and Ayyagari, 2008, p.41).In paulys test, sulfanilic acid in the reagent gives a diazonium compound in the presence of nitrous acid and hydrochloric acid, which combines with amines and phenols to form coloured azo-compounds (Nigam and Ayyagari, 2008, p.41).ConclusionMacro molecules presence in the tending(p) take ins was successfully identified by using the given chemical assays.ReferencesBochkov, A.F., Zaikov, G.E. and Afanasiev, V.A (1991) Carbohydrates. Google Books Online. visible(prenominal) at https//books.google.lk/books?id=BmPTDAnsUb0Cprintsec=frontcoverdq=carbohydrateshl=ensa=Xei=bXlKVavSGImTuAS7jYG4CQsqi=2ved=0CCMQuwUwAQv=onepageq=carbohydratesf= dishonorable (Accessed 7 May 2015).Brito-Arias, M. (2007) Synthesis and delineation of Glycosides. Google Books Online. unattached at https//books.google.lk/books?id=X9ZTg47alJkCpg=PA5dq=Tollens+testhl=ensa=Xei=2GhKVY3HOI2QuATD1YF4ved=0CDEQuwUwAwv=onepageq=Tollens%20testf= spe cious (Accessed 7 May 2015).Jenkins, A.D, Kratochvil, P., Stepto, R.F.T. and Suter, U.W. (1996) colour of basic terms in polymer science, Pure and Applied Chemistry, 68(12), pp. 22872311, ISSN Online. usable at http//www.degruyter.com/view/j/pac.1996.68.issue-12/pac199668122287/pac199668122287.xml (Accessed 6 May 2015).Malhotra, V.K. (2003) Practical Biochemistry for Students. Google Books Online. unattached at https//books.google.lk/books?id=LHa1G131MuYCpg=PA23dq=Ninhydrin+testhl=ensa=Xei=GGxKVavVMMSSuATEsYDADwved=0CB4QuwUwAAv=onepageq=Ninhydrin%20testf= faithlessly (Accessed 7 May 2015).Nigam, A. and Ayyagari, A. (2008) laboratory manual(a) in Biochemistry Immunology and Biotechnology. Google Books Online. gettable at https//books.google.lk/books?id=Ws570Ql8krACpg=PA25dq=Barfoed%E2%80%99s+testhl=ensa=Xei=i19KVbD7EJWmuQT5joHADAved=0CCEQuwUwAAv=onepageq=Barfoed%E2%80%99s%20testf=false (Accessed 7 May 2015).Nigam and Ayyagari (2008) Lab Manual in Biochemistry Immunology and Bio technology. Google Books Online. open at https//books.google.lk/books?id=Ws570Ql8krACpg=PA27dq=Seliwanoff%E2%80%99s+testhl=ensa=Xei=pWhKVcjcDoyouwSMj4HYCAved=0CB4QuwUwAAv=onepageq=Seliwanoff%E2%80%99s%20testf=false (Accessed 7 May 2015).Nigam, A. and Ayyagari, A. (2008) Lab Manual in Biochemistry Immunology and Biotechnology. Google Books Online. Available at https//books.google.lk/books?id=Ws570Ql8krACpg=PA41dq=Millon%E2%80%99s+testhl=ensa=Xei=ymxKVeXJH9GKuATY6IGwDQved=0CCoQuwUwAgv=onepageq=Millon%E2%80%99s%20testf=false (Accessed 7 May 2015).Pavia, D.L. (2005) Introduction to organic laboratory techniques A small scale approach. Google Books Online. Available at https//books.google.lk/books?id=ega5c11VHvkCpg=PA446dq=Molisch%E2%80%99s+testhl=ensa=Xei=rF5KVa39HtHguQSrvIGwCQved=0CCUQuwUwAQv=onepageq=Molisch%E2%80%99s%20testf=false (Accessed 7 May 2015).Pavia, D.L. (2005) Introduction to organic laboratory techniques A small scale approach. Google Books Online. Available at https//bo oks.google.lk/books?id=ega5c11VHvkCpg=PA451dq=Iodine+testhl=ensa=Xei=Dl9KVfTcHMuxuAT-roCIDgved=0CB4QuwUwAAv=onepageq=Iodine%20testf=false (Accessed 7 May 2015).Raymond, K.W. (2010) General Organic and Biological Chemistry. Google Books Online. Available at https//books.google.lk/books?id=iIltMoHUtJUCpg=RA1-PA344dq=Benedict%E2%80%99s+testhl=ensa=Xei=NF9KVcvTOMmxuASL9YH4Cwved=0CCcQuwUwAQv=onepageq=Benedict%E2%80%99s%20testf=false (Accessed 7 May 2015).Sim, K.S., Chin, F.S., Tso, C.P. and Thong, L.W (2008) Protein identification in latex gloves for bio-compatibility using maximum minimal variation test, in Osman, N.A.A., Ibrahim, F., Abas, W.A.B.W., Rahman, H.S.A. and Ting, H.N. (ed.) 4th Kuala Lumpur International concourse on Biomedical Engineering 2008. Google Books Online. Available at https//books.google.lk/books?id=sdG-1hN_4TYCpg=PA611dq=Xanthoproteic+testhl=ensa=Xei=gGxKVY3yA9CbuQSa74CwAwved=0CCMQuwUwAQv=onepageq=Xanthoproteic%20testf=false (Accessed 7 May 2015).Walsh, G. (200 4) Proteins Biochemistry and Biotechnology. Google Books Online. Available at https//books.google.lk/books?id=EXTEjL2wTnYCprintsec=frontcoverdq=proteinshl=ensa=Xei=M3pKVdGXJIfGuATTgoCQAQved=0CB4QuwUwAAv=onepageq=proteinsf=false (Accessed 7 May 2015).1 PageChemical Tests for BiomoleculesChemical Tests for BiomoleculesINTRODUCTIONBiomolecules are complex organic molecules. Carbon, hydrogen, type O, nitrogen and phosphorus are the atoms that make up to the highest degree of the biomolecules. These molecules form the basic structure of a living cell. The compounds much(prenominal) as amino acids, nucleotides and monosaccharides serve as the build blocks of complex biomolecules. The important biomolecules are proteins, carbohydrates, fats, hormones and nucleic acids (Kimball, 2012).CarbohydratesCarbohydrates are substances which containing the elements carbon hydrogen and oxygen and they have the global convening of Cx (H2O) y. Simple carbohydrates or the full carbohydrate family may also be called saccharides .They are the most commodious biomolecules belonging to class of organic compounds found in living organisms. The study source of metabolic energy for both animals and plants are carbohydrates (Churms, 1982). Carbohydrates link to with proteins forming glycoproteins and with lipids forming glycolipids. but they are present in DNA and RNA, which are essentially polymers. more than 75% of the dry weight of the plant world is carbohydrate in nature mainly cellulose, hemicelluloses and lignin (Reed, 2005).Carbohydrates are classified on the basis of their conduct on hydrolysis. They have been broadly divided into following three groups monosaccharides, Disaccharides, Oligosaccharides, and Polysaccharides.MonosaccharideA carbohydrate that gutternot be hydrolyzed further to give simpler unit of polyhydroxy aldehyde or ketone is called a monosaccharide. Monosaccharides are single sugars units and there general code is (CH20) n. Moreover they are color less, crystalline solids that are freely dissoluble in water but insoluble in nonpolar solvents. The backbone of monosaccharide is an unbranched carbon chain in which all the carbon atoms are linked by single bonds (Gyorgydeak and Pelyvas, 1998). One of the carbon atoms is double-bonded to an oxygen atom to form a carbonyl group each of the other carbon atoms has a hydroxyl group. If the carbonyl group is at an end of the carbon chain, the monosaccharide is an aldehyde and is called an aldose, furthermore if the carbonyl group is at every other position the monosaccharide is a ketone and is called ketoses. Glucose, fructose, galactose, and ribose are some examples of monosaccharide. The construct blocks of disaccharides like sucrose and polysaccharides such as cellulose and starch and hemicelluloses are monosaccharide (Ferrier, 1999).Figure 1.1.1 ring structure of monosaccharide molecules.https//www.google.lk/ chaseFigure 1.1.2 monosaccharide molecule showing the aldehyde and ket one grouphttp//academic.brooklyn.cuny.edu/biology/bio4fv/page/monosacchrides.htmlDisaccharidesA Disaccharide is twain monosaccharide units linked by an oxide linkage formed by the loss of a water molecule. Such a linkage amongst 2 monosaccharide units through oxygen atom is called glycoside linkage. Three most sizeable disaccharides are sucrose, lactose, and maltose. In Maltose (14) glycosidic linkage joins deuce glucose units, this occurs mainly as a breakdown product during digestion of starch by enzymes called amylases (Owusu-Apenten, 2005). Sucrose is the most abundant disaccharide in nature and its mostly found in plants which acts a good transport sugar since it is very soluble and can move in very high concentration. In Sucrose the anomeric carbon atoms of a glucose unit and fructose unit are joined. Moreover lactose the disaccharide of milk consists of galactose joined to glucose by (14) glycosidic linkage (Denniston, Topping and Caret, 2004). In additionally Sucros e and lactose are heterosaccharides and maltose is homosaccharides as well as maltose and lactose are reducing sugars. Sucrose is the simply common non reducing sugar.Figure 1.3.1 disaccharides are formed by condensing of two monosaccharide.https//www.google.lk/search?q=disaccharideses_sm=122sourcePolysaccharidesPolysaccharides are complex carbohydrates made up of galore(postnominal) monosaccharide joined together by glycosidic bond. They are large, often branched, macromolecules. Their large sizes make them more or less insoluble in water and have no sweet taste (Aspinall, 1982). When all the monosaccharide in a polysaccharide is of the same type, the polysaccharide is called a homopolysaccharide and when more than one type of monosaccharide is present, they are called heteropolysaccharides. Polysaccharides have a general formula Cn (H2O) n-1 where n can be any number between 200 and 2500. Starch glycogen and cellulose are the examples of polysaccharides (Tombs and Harding, 1998) .Figure 1.4.1 ring structure of polysaccharides molecules.https//www.google.lk/search?q=polysaccahrideses_sm=122source=lnmstbm=ischsaProteinsCells are made of protein. Proteins are the most versatile class of molecules in living organisms. All proteins contain C, H, N, O some S, P, Fe, Zn, Cu. Proteins contains 20 contrary amino acids which are encoded by the genetic code and which constitute the twist blocks of the proteins in all living organisms (Walsh, 2002). Each protein species contains one or several(prenominal) polypeptide chains of defined amino acid sequence. Their functions are catalysis, transport, hormones and structure. Amino acids are molecules containing an amine group carboxylic acid group and a side chain. Simple proteins contain only polypeptide chains Proteins can be soluble (globular proteins) and insoluble (myosin, fibrinogen) (Whitford, 2005).Figure 1.5.1 classification of proteins and there structures.https//www.google.lk/search?q=protein structurerevid=120 848340tbmOBJECTIVESTo distinguish between monosaccharides and disaccharides.To differentiate between different types of amino acids.To identify an unknown sample of carbohydrate and amino acid.MATERIALSAlbumin solutionArginine solutionBarfoed reagentBeakersBenedicts solutionBunsen burnerBurner standConcentrated sulphuric acidConcentrated nitric acidCopper sulphateFructose solutionGlucose solutionGlysin solutionIodine solutionLactose solutionMolischs reagentNinhydrin solutionPipettesSeliwanoffs reagentSodium hydroxideStarchSucrose solutionTest tubesTyrosine solutionUnknown solutionsWater bath screen FOR CARBOHYDRATES METHODOLOGYMolischs TestFive test tubes were taken with 1ml of carbohydrate solutions. Few drops of Molischs reagent were added to the testubes following with concen.sulphuric acid down the slide of the test tube. The colour channelize was observed.Iodine testThree drops of Iodine solution was added to each test tube with 1ml of each of the carbohydrate solutions. The colour change was observed.Benedicts test1ml of each carbohydrate solutions was taken in five test tubes.5ml of Benedicts reagent was added to all three test tubes. All five test tubes were placed in a water bath and heated for two minutes. The colour change was observed.Barfoed test5ml of Barfoed reagent was added with 1 ml of carbohydrate solutions. Test tubes were placed in water bath and heated for five minutes. The colour change was observed.Seliwanoff test1ml of each carbohydrate solution was added to the test tubes following with 4ml of Seliwanoff reagent. The test tubes were placed in the water bath and heated to two to three minutes. The colour change was observed. two unknown samples were taken in a test tubes and labeled A and B. Sample A was added to two test tubes. To the sample A the Iodine reagent was added and the colour change was observed. The Benedicts reagent was added to the sample A of some other test tube and was heated in general flame for two minutes and th e colour change was observed.The sample B was added to 4 test tubes. One drop of Iodine reagent was added to the sample B test tube and colour change was observed following with Benedicts reagent, Barfoed reagent and the Seliwanoff reagent were added to the remain test tubes with sample B and was heated in the water bath for three minutes and the colour change was observed.TEST FOR AMINO window pane METHODOLOGYNinhydrin test1ml of Ninhydrin solution was added into 0.5 ml of 0.02 % amino acid solution in four test tubes. The test tubes were placed in water bath and heated for three to four minutes. The colour change was observed.Xanthoproteic Test2ml of conc. Nitric acid was added to 2ml of 0.02% amino acid solution in four test tubes. The test tubes were placed in water bath for two minutes and the colour change was observed.Millons TestFour drops of Millons reagent was added into 2ml of 0.02% of amino acid solution in four test tubes. The test tubes were placed in water bath for four minutes and the colour change was observed.Biurete Test3ml of 10% of sodium hydroxide was added drop intelligent to 1% of copper sulphate. The colour change was observed.Two unknown samples were taken in test tubes and labeled C and D. Sample C was added into two test tubes. To the sample C the Biurete reagent was added and the colour change was observed. The Millons reagent was added to the sample C of another test tube and was heated in general flame for two minutes and the colour change was observed.The sample D was also added into two test tubes. Biurete reagent was added to the sample B test tube and colour change was observed. Besides Millons reagent were added to the remaining test tube with sample B and was heated in the water bath for three minutes and the colour change was observed.RESULTSTest for carbohydratesTest for amino acids watchwordIn Molischs test all the carbohydrate solution gave a haughty result, so as its a general test to confirm the molecule is carbo hydrate. Iodine test is performed to separate the polysaccharide from monosaccharide and disaccharide as a result in this test only starch gave a positive result since its unbranched molecule. Glucose has a free aldehyde group and fructose has a free ketone group. Thus they react with Benedicts reagent and reduce it to form a red-faced orange colour, which is a positive indication of Benedicts chemical reaction .The copper (II) ions in the Benedicts solution are reduced to Copper (I) ions, which causes the colour change. Complex carbohydrates such as starches do not react positive with the Benedicts test.Buiret solution is a blue liquid that changes to purple when proteins are present and to pink in the presence of short chains of polypeptides. The cause of this colour change is because of the copper atom of the Biuret solution reacts with the peptide bonds.Avoid spilling Ninhydrin solutions on your skin, as the resulting stains are difficult to remove. When handling with Concentra ted Sulphuric acid pall safety garments to avoid Sulphuric acid getting on self. Do not over heat the amino solutions in water bath since all the proteins may denature moreover colour change cannot be observed.CONCLUSIONThe unknown solution A is sucrose and its a non reducing sugar since in Iodine and Benedicts test it showed a negative result where there was no colour change in addition to unknown solution B is glucose which is a reducing sugar because in Iodine and Seliwanoff test it gave a negative result remaining pallid and in Benedicts and Barfoed test it gave a positive result changing its colour from green precipitate to reddish colour solution concluding solution B is glucose.The unknown solution C is protein since positive result was obtained and the solution turned pink in Biurete and Millons reagent along with the solution D is an amino acid because it remained colourless in Millons test and turned light blue in Biurete test resulting both in negative.ReferencesAspinal l, G. (1982). The Polysaccharides. world-class ed. New York Academic Press. Google books Online books Available at http//books.google.lk (Accessed third July 2014).Churms, S. (1982). Carbohydrates. inaugural ed. Boca Raton, Fla. CRC Press. Google books Online books Available at http//books.google.lk (Accessed 3rd July 2014).Denniston, K., Topping, J. and Caret, R. (2004). General, organic, and biochemistry. first ed. Boston McGraw-Hill Higher Education. Google books Online books Available at http//books.google.lk (Accessed 3rd July 2014).Ferrier, R. (1999). Carbohydrate chemistry. first ed. Google books Online books Available at http//books.google.lk (Accessed 3rd July 2014).Gyorgydeak, Z. and Pelyvas, I. (1998). Monosaccharide sugars. 1st ed. San Diego Academic Press. Google books Online books Available at http//books.google.lk (Accessed 3rd July 2014).Kimball, L. (2012). Biomolecules. 1st ed. Delhi Research World. Google books Online books Available at http//books.google.lk (A ccessed 3rd July 2014).Owusu-Apenten, R. (2005). Introduction to food chemistry. 1st ed. Boca Raton, Fla. CRC Press. Google books Online books Available at http//books.google.lk (Accessed 4th July 2014).Reed, D. (2005). Biomolecular archaeology. 1st ed. Carbondale Center for Archaeological Investigations, Southern Illinois University, Carbondale. Google books Online books Available at http//books.google.lk (Accessed 3rd July 2014).Tombs, M. and Harding, S. (1998). An macrocosm to polysaccharide biotechnology. 1st ed. London Taylor Francis. Google books Online books Available at http//books.google.lk (Accessed 4th july2014).Walsh, G. (2002). Proteins. 1st ed. Chichester J. Wiley. Google books Online books Available at http//books.google.lk (Accessed 6th July 2014).Whitford, D. (2005). Proteins. 1st ed. Hoboken, NJ J. Wiley Sons. Google books Online books Available at http//books.google.lk (Accessed 6th July 2014).