Carbohydrate Detection Test

When combined together to form polymers, carbohydrates can function as long term food storage molecules, as protective membranes for organisms and cells, and as the main structural support for plants and constituents of many cells and their contents. Carbohydrates are tests by using Monolith's test and Benedicts test. Monolith's test is a sensitive chemical test for the presence of carbohydrates, based on the dehydration of the carbohydrate by sulfuric acid to produce an allayed, which condenses with two molecules of phenol, resulting in a red- or purple-colored compound.

Benedicts test allows for the detection of the presence of reducing sugars (sugars with a free allayed or ketene group). All incarcerations are reducing sugars since all of them have active carbonyl group. Some disaccharide that are exposed to a carbonyl group are also reducing sugars but less reactive than incarcerations. By mixing the sugar solution with Benedicts solution and heating them, a redo reaction will occur. The copper (II) sulfate present in Benedicts solution reacts with electrons from allayed or ketosis group of reducing sugars to form cuprous oxide, a De brown precipitate.Proteins are inherently important to any living organism.

They control cell process, provide support, and transport substances within a cell. They can even take the form of enzymes and hormones, regulating cells. These important cells are made up of polymers of amino acids whose functional groups are a carbonyl group and a free amino group. Both organic compounds contribute to our lives, and our health is heavily dependent on them. Knowing how they operate is to partially understand the mechanics of the human body.

Proteins are tests by using Unhidden solution andMillion's reagent. Unhidden is a chemical used to detect ammonia or primary and secondary amines. When reacting with these free amines, a deep blue or purple color known as Ranchmen's purple is evolved. Unhidden is most commonly used to detect fingerprints, as amines left over from peptides and proteins (terminal amines or lysine residues) sloughed off in fingerprints react with Unhidden.

Million's reagent is an analytical reagent used to detect the presence of soluble proteins. A few drops of the reagent are added to the test solution, which is then heated gently.A reddish- rowan coloration or precipitate indicates the presence of tyrosine residue which occur in nearly all proteins. Lipids are one class of aliphatic hydrocarbon-containing organic compounds essential for the structure and function of living cells. Lipids are characterized by being water-insoluble but soluble in unpopular organic solvents.

Examples of lipids are fats and oils. Fats and oils are made from two kinds of molecules: glycerol (a type of alcohol with a hydroxyl group on each of its three carbons) and three fatty acids joined by dehydration synthesis.LAB 3. 1 : CARBOHYDRATES DETECTION TEST Objectives To detect the presence of carbohydrates in a food sample Materials Test tubes Monolith's Reagent Benedicts reagent Glucose Solution Sucrose Solution Concentrated Sulfuric Acid Water bath Methodology Monolith's test 1 . 2 drops of Monolith's reagent was added to 2 ml of both glucose solution and sucrose solution and the solution was mixed thoroughly. 2.

By inclining the tube, ml of concentrated HASPS was poured GENTLY down the side of the test tube. 3.If the test is positive, a purple color will appear at the interface of the sugar and a green color will appear if it is disregard. I Sucrose I Results I Glucose Initial Color Final Color I Colorless I Colorless I I Purple I Light purple I Benedicts test 1 . 1 ml of both glucose solution and sucrose solution was added to ml of Benedicts solution, and both tubes were shaken. 2.

Each tube was placed in a boiling water bath and heated for 3 minutes. 3. After 3 minutes, the tubes were removed from the heat and the tubes are allowed to be cool. . A green, yellow or red precipitate was formed, the test is positive for reducing sugars.

I Glucose I Sucrose I Initial Color I Blue I Blue Final Color I Green I Blue Discussions 1. Monolith's Test a) When the sugar solution is combined with a small amount of Monolith's reagent in a test tube and a small amount of concentrated sulfuric is poured gently down the side of the test tube, a purple ring at the interface between the acid and sugar solution layer is formed. B) The purple ring formed indicates a positive test. ) Sulfuric acid is used to dehydrate the carbohydrate to produce an allayed, which condenses with two molecules of phenol resulting in a purple-colored compound. D) Although all carbohydrates react positively with Monolith's reagent, UT the intensity of purple color will be different because incarcerations give a rapid positive test while disaccharide and polysaccharides react slower. 2.

Benedicts Test a) The Benedicts test is used to identify the presence of incarcerations and reducing disaccharide sugars.A green, yellow or red precipitate indicates the presence of the reducing sugar. A brick-red precipitate indicates that a large amount of reducing sugar is present while a yellow or a green precipitate indicates the presence of lesser amount of reducing sugar. If the original pale blue color of the elution remains, this indicates that reducing sugar is not present. B) The color of Benedicts solution after heated turns from blue to green indicates the presence of reducing sugar and incarcerations which is glucose.Since glucose solution used in this experiment is less, so it will reduce the blue copper (II) sulfate in Benedicts solution to form a green precipitate instead of brick-red precipitate.

C) The sucrose solution remains unchanged as sucrose is a non-reducing sugar. To get positively reaction, the sucrose solution needs to be heated with hydrochloric acid first to hydroxyl the non-reducing sugar to its constituent incarcerations (glucose and fructose) which are reducing sugar. Conclusion 1 . Glucose and sucrose are carbohydrates as they showed positive reaction with Monolith's reagent.

2.Glucose is a reducing sugar as it reduced the Benedicts solution from blue to green color. 3. Sucrose is a non-reducing sugar because it showed no reaction with Benedicts solution. LAB 3. 2 : PROTEIN DETECTION TEST To detect the presence of protein in a food sample Million's Reagent 0.

1% Unhidden solution Casein 2% egg albumin 0. MM Tyrosine 0. MM Glycerin Million's test 1. Mil of casein, 2% egg albumin and 0. MM tyrosine were placed into separate labeled 12 x 75 mm test tubes.

2. 3 drops of Million's reagent were added to all test tubes and the test tubes were immersed in the boiling water bath. . The tubes were cool and the colors formed were recorded. I Casein 12% Egg Albumin | 0. 1 M tyrosine I Initial Color I Colorless I Colorless I Colorless I Final Color I Light Red I Brick Red Precipitate I Dark Red I Unhidden test 1.

Mil of casein, 2% egg albumin and 0. MM tyrosine was placed into separate labeled 12 x 75 mm test tubes. 2. Drops of 0. 1% Inherit solution was added to each tube.

(CAUTION: UNHIDDEN IS A CARCINOGEN- AVOID DIRECT CONTACT) 3. The tubes were immersed in the boiling hot-water bath. 4. The results were recorded. Casein | 2% Egg Albumin 1 0. M Glycerin I Final Color I No change I Purple I Violet I Discussion 1.

Million's Test a) The reaction between Million's reagent and the test solutions show positive reactions if the test solution contains protein. B) The Million's test was successful because it showed the different types and how strong the proteins are based on the intensity color of the result. ) It is possible to use the Million's test to determine the concentration of proteins because (for most proteins) peptide bonds occur with approximately the same frequency per gram of material.The intensity of the color is directly proportional to the protein concentration.

D) Million's reagent consists of mercury dissolved in nitric acid (forming a mixture of mercuric & murderous nitrates). When Million's reagent is added to a protein (0. MM of tyrosine), a white precipitate is formed (the initial color of tyrosine when added with 3 drops of Million's reagent) which turns dark red on heating. This test is given by protein which yield tyrosine on hydrolysis (due to the presence of phenol group).

Consequently, any protein containing tyrosine will give a positive test of a pink to dark-red color.The red color is probably due too mercury salt of nitrated tyrosine. E) Million's test is not specific for proteins (it actually detects phenol compounds), and so must be confirmed by other tests for proteins such as the Unhidden reaction. F) Caution: Million's reagent is highly toxic and highly corrosive. 2. Unhidden Test a) Unhidden reaction is chemical reaction to detect existence of amino acids.

When reacting with free amines from the amino acid, blue or purple color is produced. The final color can vary based on the type(s) of amino acids present. ) The casein solution showed negatively reaction. This is because casein has a pH value of 4. 6.

The reaction of amino acid with Unhidden solution is very influenced by the acidity of Unhidden. This meaner casein is insoluble in solution with a pH less than 4. 6. We assumed that Unhidden used in the experiment has a pH value of more than 4. 6, so casein was soluble in that Unhidden solution thus showed no powder-like precipitate at the bottom solution.

) The egg albumin and glycerin solution showed different intensity of purple color because they contain different types of amino acids.The egg albumin contains 18 types of amino acids such as Elaine, seclusion, serine, argentine, Lucien, throne, aspartic acid, lysine, thyrotrophic, Sistine, Mennonite, tyrosine, glutamine acid, phenylalanine, valise, histamine, praline, and glycerin. Glycerin is the smallest of the 20 amino acids commonly found in proteins. D) Precaution: Avoid spilling Unhidden solutions on your skin, as the resulting stains are difficult to remove. E) Precaution: When handling the experiment, we must avoid direct intact with Unhidden because Unhidden is a carcinogen.