I NUR 4
POLICARPIO, JOHN PAUL (A & B)
QUERUBIN, KIMBERLY (C & D)
QUILALA, REGENE (E & F1)
RAMOS, PRACCEDES (F2a & F2b)
SABALDICCA, VENZ (F2c & F2d)
Lipids are organic compounds found in living organisms that are insoluble or slightly soluble in water but soluble in non-polar organic solvents.
Lipids can be classified into four groups which are -fats, oils, and waxes, -compound lipids, -steroids, and -derived lipids.
Various experiments are done on lipids. Some tests are for saturation, presence of certain compounds, or for the different chemical reactions that lipids undergo.
Lipids may be composed of esters, amides, alcohols, cyclic, acyclic, or polycyclic structures, and may also be a combination of these.
General Objective: At the end of the experiment, students must be able to familiarize themselves with the different classes of lipids and to be able to identify each kind of lipid of lipid based on the chemical properties of its hydrolyzed products.
A. SPOTTING EFFECT
Specific Objective: Test for the presence of lipids by means of locating translucent spots/area in the filter paper.
Specific Objective: To test for the solubility of the suspected lipid-containing samples.
C. TEST FOR UNSATURATION (BROMINE WATER TEST)
To test for unsaturation of lipids through a change in colour or discoloration of the bromine water.
To test for the presence of carbon-carbon double bonds.
D. ACROLEIN TEST
Specific Objective: To test for the presence of glycerol/glycerin or fats.
E. AMMONIUM MOLIBDATE TEST
F.1. EXTRACTION OF BRAIN LIPIDS
F.2. DETECTION OF BRAIN LIPIDS
A.) Molisch Test
Specific Objective: To determine the presence of carbohydrates in a lipid solution
B.) Ninhydrin Test
Specific Objective: To determine the reaction of the ninhydrin reagent to the residue B dissolved in water.
C.) Soda-Lime Test
To determine the change in color of the moistened red and blue litmus paper when exposed to the vapor of the heated mixture of Soda-lime and Residue B.
To determine whether the mixture is an acid or a base by noting the change in color of the litmus paper.
D.) Leibermann-Burchard Test
To determine the change in color made when acetic anhydride and sulfuric acid were added to a tube containing residue C dissolved in methylene chloride and to a tube containing vegetable oil
To compare residue c and vegetable oil through the intensity and color of their resulting solution
RESULTS AND DISCUSSIONS
A. SPOTTING EFFECT
Visible Positive Result: Translucent spot (area where light passes through) Sample| Observations|
1(Vegetable Oil)| Presence of translucent spot|
2(Vitress hair polish)| NR|
3(Pantene Conditioner)| NR|
4(Collagen Age Stick)| Presence of translucent spot at the sides of the sample| 5(Body Lotion)| NR|
Grease Spot Test
This simple test for lipids has been used for centuries. Lipids that are derived from glycerol and sphingosine, a long-chain base that is the backbone of sphingolipids, will produce translucent "spots" or "stains" on fabrics. If the lipid is not a derivative of glycerol or sphingosine, it will not produce a translucent spot on the fabric. The grease-spot test requires that the lipid be in liquid form. Semi-solid lipids, because of the higher degree of saturation in the fatty acid chains, have melting points higher than room temperature and therefore need to be mildly heated before testing. Also, it was stated in the test to dissolved the suspected lipids in methylene chloride, that is because, methylene chloride is a non-polar solvent, and lipids are mostly non-polar, thus non polar dissolves in non polar. And if the suspected lipid is a lipid, then it won’t affect its polarity and we...