Experiment 6: Monosaccharides and Disaccharides PDF

BIOCHEMISTRY LABI UNIT 1 I EXPERIMENT 6 I MONO AND DISA BSN 1- C I UNIVERSITY OF SAN AGUSTIN I A.Y. 2024 - 2025 I 1ST SEMESTER ISABILLE NICOLE V. ROBLES MAIN TOPIC SUB TOPIC I SUB TOPIC II SUB TOPIC III SUB TOPIC IV IMPORTANT NOTED EXPERIMENT NO....

BIOCHEMISTRY LABI UNIT 1 I EXPERIMENT 6 I MONO AND DISA BSN 1- C I UNIVERSITY OF SAN AGUSTIN I A.Y. 2024 - 2025 I 1ST SEMESTER ISABILLE NICOLE V. ROBLES MAIN TOPIC SUB TOPIC I SUB TOPIC II SUB TOPIC III SUB TOPIC IV IMPORTANT NOTED EXPERIMENT NO. 6 - MONOSACCHARIDES AND DISACCHARIDES CLASIFICATION OF CARBOHYDRATES MONOSACCHARIDE Compose of one sugar units. Simple sugars. DISACCHARIDE Compose of two monosaccharide units. OLIGOSACCHARIDES Oligo = “a few”. Usually 2 to 10 monosaccharide units. POLYSACCHARIDES Are polymers of the simple sugars usually more than 10 monosaccharide units. THE THREE COMMON MONOSACCHARIDES GLUCOSE Is the main type of sugar in the blood and is the major source of energy for the body’s cells. GALACTOSE Is a C - 4 epimer of glucose. It is known as the brain sugar. It supports the brain development of infants. FRUCTOSE A fruit sugar. Is the simplest ketonic sugar. It is the sweetest naturally occurring carbohydrates. DISACCHARIDES Composed of two monosaccharide subunits hooked together by an acetal linkage. MALTOSE ά-D-glucose linked to β-D-glucose by an ά (1-4) glycosidic bond A reducing sugar Repeating disaccharide unit of starch. Present in malt, the juice from sprouted barley and other cereal grains. Maltose is a reducing sugar. ROBLES BSN 1-C 1ST YEAR  BIOCHEMISTRY LABI UNIT 1 I EXPERIMENT 6 I MONO AND DISA BSN 1- C I UNIVERSITY OF SAN AGUSTIN I A.Y. 2024 - 2025 I 1ST SEMESTER ISABILLE NICOLE V. ROBLES MAIN TOPIC SUB TOPIC I SUB TOPIC II SUB TOPIC III SUB TOPIC IV IMPORTANT NOTED EXPERIMENT NO. 6 - MONOSACCHARIDES AND DISACCHARIDES SELIWANOFF’S TEST Use to differentiate ketohexoses from aldohexoses. In the concentrated HCl, ketones undergo dehydration to yield furfural derivatives more rapidly than do aldoses. These derivatives form complexes with resorcinol to yield deep red color. It is a timed color reaction specific for ketohexoses. LACTOSE β -D-galactopyranosyl-(1-4) β-D-glucopyranoside Made up of β -D-galactose linked to β -D-glucose by a β (1-4) glycosidic bond (galactose: “brain sugar”) A reducing sugar Is the principal sugar present in milk; it makes up about 5 to 8 percent of human milk and 4 to 6 percent of cow’s milk. PHENYLHYDRAZINE REACTION The ketoses and aldoses react with phenylhydrazine to produce a phenylhydrazone which in turn reacts with SUCROSE another two molecules of phenylhydrazine to form the Made up of β-D-fructose linked to an ά-D-glucose osazone. by a β (2-1) glycosidic bond Glucose, fructose and mannose produce needle-shaped A non - reducing sugar. yellow osazone crystals. Whereas lactosazone in Table sugar. mushroom-shaped. Different osazones show crystals of different shapes. Maltose produces star-shaped (flower- shaped) crystals. PHLOROGLUCINOL - HCL TEST It involves the formation of furfural derivatives in the presence of concentrated HCl. The test is used to specifically detect galactose and lactose in a sample solution. TEST FOR CARBOHYDRATES MOORE’S TEST PHENYLHYDRAZINE MOLISCH TEST REACTION SELIWANOFF’S TEST PHLOROGLUCINOL - HCL TEST REDUCTION TESTS FEHLING’S TEST The blue alkaline cupric hydroxide present in solution, when heated in the presence of reducing sugars, gets reduced to yellow or red cuprous oxide and it gets precipitated. Hence, formation of the colored precipitate indicates the presence of reducing sugars in the test solution. TEST FOR CARBOHYDRATES MOORE’S TEST Test for the presence of carbohydrates in a substance in the influence of a concentrated alkali. MOLISCH TEST Is a general test for carbohydrates where sugars are mixed with α-naphthol, the test tube is inclined and about 1mL of concentrated sulphuric acid is added along the sides of the tube. The color formed is due to the reaction of alpha-naphthol with furfural and/or its derivative formed by the dehydration of sugars by concentrated sulfuric acid. All carbohydrates react positively with this reagent ROBLES BSN 1-C 1ST YEAR  BIOCHEMISTRY LABI UNIT 1 I EXPERIMENT 6 I MONO AND DISA BSN 1- C I UNIVERSITY OF SAN AGUSTIN I A.Y. 2024 - 2025 I 1ST SEMESTER ISABILLE NICOLE V. ROBLES MAIN TOPIC SUB TOPIC I SUB TOPIC II SUB TOPIC III SUB TOPIC IV IMPORTANT NOTED EXPERIMENT NO. 6 - MONOSACCHARIDES AND DISACCHARIDES BENEDICT’S TEST TOLLEN’S TEST As in Fehling’s test, the reducing sugar because of having Is also known as silver mirror test potentially free aldehyde or keto group reduce cupric A qualitative test that distinguishes aldehydes from ketones on hydroxide in alkaline solution to red colored cuprous oxide the principle that aldehydes are easily oxidized than ketones Formation of red, yellow or green color/precipitate. BARFOED’S TEST PICRIC ACID TEST Oxidizes monosaccharides but not oligosaccharides; Test for the presence of reducing sugars Picric acid is a disaccharides are less easily oxidized but are oxidized if they chemical compound formally called 2,4,6-trinitrophenol (TNP). undergo prolonged heating A toxic yellow crystalline solid and one of the most acidic phenols It reacts with metal to form metal picrates Formation of MAHOGANY RED SOLUTION TROMMER’S TEST REDUCTION TEST Is like the Benedict’s test for reducing sugars only that it FEHLING’S TEST NYLANDER’S TEST involves treating the sample with concentrated H2SO4 BENEDICT’S TEST TOLLEN’S TEST which results to acid hydrolysis of disaccharides forming BARFOED’S TEST PICRIC ACID TEST monosaccharides TROMMER’S TEST LABORATORY RESULTS NYLANDER’S TEST A reduction test that uses bismuth subnitrate which is reduced to black precipitate bismuth when reacted with a reducing sugar ROBLES BSN 1-C 1ST YEAR  BIOCHEMISTRY LABI UNIT 1 I EXPERIMENT 6 I MONO AND DISA BSN 1- C I UNIVERSITY OF SAN AGUSTIN I A.Y. 2024 - 2025 I 1ST SEMESTER ISABILLE NICOLE V. ROBLES MAIN TOPIC SUB TOPIC I SUB TOPIC II SUB TOPIC III SUB TOPIC IV IMPORTANT NOTED EXPERIMENT NO. 6 - MONOSACCHARIDES AND DISACCHARIDES ROBLES BSN 1-C 1ST YEAR  BIOCHEMISTRY LABI UNIT 1 I EXPERIMENT 6 I MONO AND DISA BSN 1- C I UNIVERSITY OF SAN AGUSTIN I A.Y. 2024 - 2025 I 1ST SEMESTER ISABILLE NICOLE V. ROBLES MAIN TOPIC SUB TOPIC I SUB TOPIC II SUB TOPIC III SUB TOPIC IV IMPORTANT NOTED EXPERIMENT NO. 6 - MONOSACCHARIDES AND DISACCHARIDES ROBLES BSN 1-C 1ST YEAR