1. Angelica AdranedaCarla CadwalladerCharissa Marie Agustin Norilene CayabyabReylan Vence Almarez Keisha Mae DabuJance Venice Biliran

2. Carbohydrates, or saccharides, aresugars and starches, which provideenergy for humans and animals, andcellulose which make up many plantstructures. Carbohydrates are polyhydroxy aldehydesor ketones and yield these products uponhydrolysis. Carbohydrates are representedby the general formula Cn(H2O)n and 3. Functions of Carbohydrates in humanbody:Carbohydrate oxidation provides Carbohydrates storage, in the form of glycogen,provides a short-term energy reserve. Carbohydrates supply carbon atoms for thesynthesis of other biochemical substances(proteins,lipids, and nucleic acids.) Carbohydrates form part of the structuralframework of DNA and RNA molecules. Carbohydrates linked to lipids are structuralcomponents of cell membranes. Carbohydrates linked to proteins function in avariety of cell-cell-molecule recognition process. 4. Test for Carbohydrates Molish Test Iodine Test Benedicts and Fehlings Test. Seliwanoffs Test Barfoeds Test Osazone Test 5. Principles behind the test ofCarbohydrates Molisch Test-When carbohydrates areexposed to concentrated H2SO4 in thepresence of heat of dilution, they undergodehydration to form furaldehydederivatives. Hexoses form hydroxymethylfuraldehyde. It condenses with a-naphtholto form a colored chromogen. 6. Iodine Test Starch is made up of two polysaccharidesfractions amylase and amylopectin. Iodine istrapped inside the helix and the complex isresponsible for the blue color. On heating, thehelical coil unwinds, which is equivalent todenaturation. Iodine is released and the colordisappears. On cooling, renaturation takesplace and iodine is again bound to the reformedhelix. 7. Fehlings Test and Benedicts Test Under alkaline conditions, reducing sugarstautomerize to enediol. These reducing sugarscupric to cuprous ion. The cuprous hydroxideformed is then converted to brick-red cuprousupon heating 8. If reducing sugars are present, thesolution should begin to changecolors as a rust or red coloredprecipitate forms. If reducingsugars are not present, thesolution will remain blue or green. 9. Seliwanoffs Test The principle of the test is the formation ofhydroxymethyl furaldehyde and itscondensation with resorcinol, which forms acolored chromogen. 10. Barfoeds Test (Modified) Under slightly acidic conditions,monosaccharides easily reduce Cu+ to Cu+.On treatment with phosphomolybdic acid, Cu+reduces colorless phosphomolybdic acid to bluephosphomolydous acid. 11. Osazone Test When reducing sugars are treated withphenylhydrazone first, phenylhydrazone isformed. On heating, the hydrazone furtherreacts with phenylhydrazone to formosazones. 12. Reducing and Non Reducing Sugar(s) Reducing Sugars-Sugars that containaldehyde groups that are oxidised tocarboxylic acids. Non-Reducing Sugars-a carbohydrate that isnot oxidized by a weak oxidizing agent (anoxidizing agent that oxidizes aldehydes butnot alcohols, such as the Tollens reagent) inbasic aqueous solution.e.g sucrose, which contains neither ahemiacetal group nor a hemiketal group and,therefore, is stable in water. 13. Molisch Test-is a sensitive chemical testfor all carbohydrates, and somecompounds containing carbohydrates in acombined form, based on the dehydrationof the carbohydrate by sulfuric acid toproduce an aldehyde which thencondenses with the phenolic structureresulting in a red or purple-coloredcompound. 14. Shows positive testfor:All carbohydrates.Monosaccharides give arapid positive test. Disaccharides andPolysaccharides react Reactions:slower.The test reagentdehydrates pentoses toform furfural (top reaction)and dehydrates hexosesto form 5-hydroxymethylfurfural (left reaction). Thefurfurals further react with-naphthol present in thetest reagent to produce apurple product 15. Violet ring means Carbohydrate ispresent. 16. Observation: In hydrolysis, Disaccharideshydrolyzed into simple sugar. Monosaccharides do not hydrolyzed becausethey are simpler enough to undergo thisprocess. Positive color: brick precipitate 17. Glucose, Fructose and Galactose are thesugars that are obtained through hydrolysis. Upon hydrolysis, sucorse hydrolyzed intoglucose and fructose; maltose into 2 moles ofglucose units; lactose into glucose andgalactose. 18. it is a qualitative test for detection ofpolysaccharides. Iodine complexes with polysaccharides. Starchform a blue-black product, while glycogen and partially hydrolysed starch givered-brown color. As some of thepolysaccharides are not water soluble a suspension or a solidcan be directly tested by placing the iodinesolution 19. Shows positive test for: StarchA positive test is indicated by: formation of blue-black color. (bottom left shows positive result,while bottom right is the control test.) Another example offormation of blue-blackcomplex(bottom right). 20. Bials Test is to determine the presence of pentoses(5C sugars). The components of thisreagent are resorcinol, HCl, and ferric chloride. In thistest, the pentose is dehydrated toform furfural and the solution turns bluish and aprecipitate may form. 21. A positive test is indicated by: The formation ofa bluish. All other colors indicate a negativeresult for pentoses. (Note that hexosesgenerally react to form green, red or brownproducts.) 22. Barfoeds reagent, cupric acetate in acetic acid,is slightly acidic and is balanced so that is canonly be reduced by monosaccharides but notless powerful reducing sugars. Disaccharidesmay also react with this reagent, but thereaction is much slower when compared tomonosaccharides. 23. Shows positive test for: ReducingMonosaccharides Reactions:reducing monosaccharides areoxidized by the copper ion in solution to form acarboxylic acid and a reddish precipitate ofcopper (I) oxide within 3 minutes. Reducingdisaccharides under the same reaction but doso at a slower rate. 24. The formation of reddish precipitate(top right) indicate positive result. 25. Benedicts test allows us to detect the presenceof reducing sugars (sugars with a free aldehydeor ketone group). All monosaccharides arereducing sugars; they all have a free reactivecarbonyl group. Some disaccharides haveexposed carbonyl groups and are also reducingsugars. Other disaccharides such as sucroseare non-reducing sugars and will not react withBenedicts solution. Starches are also non-reducing sugars. The copper sulfate (CuSO4)present in Benedicts solution reacts withelectrons from the aldehyde or ketone group ofthe reducing sugar to form cuprous oxide 26. Benedicts Test Shows positive test for: Reducing SugarsThe formation of a reddish precipitate indicatespositive result Reactions:Reducing sugars are oxidized by the copper ion insolution to form a carboxylic acid and a reddishprecipitate of copper (I) oxide. 27. Glucose,Galactose andFructose gives positiveresult while sucroseshows negative result. 28. Seliwanoffs Test distinguishes between aldoseand ketose sugars. Ketoses are distinguishedfrom aldoses via their ketone/aldehydefunctionality. If the sugar contains a ketonegroup, it is a ketose and if it contains analdehyde group, it is an aldose. This test isbased on the fact that, when heated, ketosesare more rapidly dehydrated than aldoses.. 29. Reactions: The test reagent dehydratesketohexoses to form 5-hydroxymethylfurfural. 5-hydroxymethylfurfural further reacts withresorcinol present in the test reagent to producea red product within two minutes. Aldohexosesreact to form the same product, but do so moreslowly. Show positive test for: Ketoses 30. The dehydrated ketose then reacts with theresorcinol to produce a deep cherry red color (topright). Aldoses may react slightly to produce afaint pink color. 31. Has function in identifying the aldehyde orhemiacetal group that will be oxidated bytollens reagent. Tollens reagent is a chemicalreagent most commonly used to determinewhether a known carbonyl-containingcompound is an aldehyde or a ketone. 32. The Solution that produce positive is glucose andfructose, but the lactose, sucrose and sample isnegative in result. Postive result will yieldsilver mirror appearance. 33. Carbohydrate specific reaction in which carbsreact with phenylhydrazine to form osazonesi.e. crystals of specific shape,thus the testconfirms the presence of a particular sugar. This is a test for reducing carbohydrate,reducing disaccharides and manymonosaccharides to be identified with theformation of osazone crystals. 34. Color Reaction: C-Osazone Test: this test is forlactose. Sugar is heated with phenyl hydrazinehydrochloride, sodium acetate and acetic acid.Yellow crystals of Osazone are formed. D-Resorcinol test for ketoses: Crystals of resorcinolare added to solution and heated with equalvolume of concentrated HCL. Pink color isformed. 35. Positive Test: Carbohydrates and 1,2-diols. Osazone Formation involves hydrazone formationat C-1 of an aldose (or C-2 of ketose) andoxidation of C-2 (or C-1) of an alcohol group of aketone (or an aldehyde). 36. Hans Molisch Hans Molisch (December 6, 1856, Brnn,Habsburg Moravia - December 8, 1937, Wien,Austria) was a Czech-Austrian botanist. He taught as a professor at the GermanUniversity of Prague (1894-), Vienna University(1909-1928), Tohoku Imperial University (nowTohoku University, Japan; 1922-1925), and auniversity in India. Hans Molisch expanded on Julius von Sachsswork by developing starch pictures in intactleaves by using actual photographic negativesas masks over the illuminate leaves. 37. Bernard Coutois Bernard Courtois, also spelled BarnardCourtois, (12 February 177727 September1838) was a French chemist born in Dijon,France. Courtois was extracting sodium and potassiumcompounds from seaweed ash. Once thesecompounds were removed, he added sulfuricacid (H2SO4) to further process the ash. Heaccidentally added too much acid and a violetcolored cloud erupted from the mass. The gascondensed on metal objects in the room,creating solid iodine. Today, iodine is chiefly 38. Stanley Rossiter Benedict Stanley Rossiter Benedict (17 March 1884 21 December 1936) is an American chemistbest known for discovering Benedicts reagent,a solution that detects certain sugars. Benedict was born in Cincinnati, and went tothe University of Cincinnati. After a year, hewent to Yales Department of PhysiologicalChemistry for training in metabolism andphysiology. 39. Hermann von Fehling Hermann von Fehling, born 1812, discoveredFehlings solution as an oxidizing agent andan analytical reagent for aldehydes andsugars; elucidated composition of paraldehydeand metaldehyde; prepared phenyl cyanide. 40. Christen Thomsen Barfoed Christen Thomsen Barfoed (June 16, 1815 April 30, 1899) was a Danish chemist whodevised a way to detect monosaccharidesugars in a solution, now known as theBarfoeds test. Barfoed is also credited withhaving introduced systematic chemicalanalyses in Danish agricultural sciences. 41. Emil Fischer The famous German chemist Emil Fischerdeveloped and used the reaction to identifysugars whose stereochemistry differed byonly one chiral carbon. It is used inOsazone test. 42. Manfred Bial Manfred Bial (18691908) was a Germanphysician who invented a test for pentosesusing orcinol, now known as Bials test. 43. Heinrich Hlasiwetz Austrian chemist Heinrich Hlasiwetz (1825-1875) is remembered for his chemical analysisof phloroglucinol. 44. Reference(s): http://www.pua.edu.eg/Version2/Courses2/Dentistry http://www.chem.boun.edu.tr/webpages/courses/Ch http://www.esu.edu/~scady/Experiments/Carbohydr http://www.authorstream.com/Presentation/raniasho http://en.wikipedia.org