Determination of Saponification and Iodine Number of Some Lipids
DETERMINATION OF SAPONIFICATION AND IODINE NUMBERS OF SOME LIPIDS
A.L. ASCANO1 C.V. OPONDA1
1INSTITUTE OF BIOLOGY
UNIVERSITY OF THE PHILIPPINES, DILIMAN, QUEZON CITY, PHILIPPINES
DATE PERFORMED: FEBRUARY 19, 2013
INSTRUCTOR’S NAME: FRANCESCA N. BELTRAN
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ABSTRACT
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INTRODUCTION
Lipids are long aliphatic hydrocarbon chains which are either branched or unbranched that can form rings and may have unsaturation. [8] They are products of animal or vegetable origin which are extracted with either ether, chloroform, benzene, petroleum, carbon disulfide. [6] They can be described as substances which are insoluble in water but soluble in fat solvents. [5] Lipids are compounds that share properties based on their structural similarities mainly a preponderance of nonpolar groups. [4] It includes compounds such as fatty acids, glycerolipids, sphingolipids, terpenes, steroids and carotenoids. [7]
Lipids can be classified as: saponifiable lipids and unsaponifiable lipids. Saponifiable lipids are open-chain compounds containing polar heads and long nonpolar chains. Among the saponifiable lipids are triacylglycerols, waxes, sphingolipids and phospholipids. Unsaponifiable lipids on the other hand are those with fused rung compounds such as steroid and cholesterol. [8]
Molecular weight can be calculated by
MW= (3 x g sample)/(mol KOH) (1)
Lipids of natural origin are usually obtained from their esters by alkaline hydrolysis. Such procedures allow the yield of complex mixtures of fatty acids which are resolvable with relative difficulty. Description of fatty acids therefor is restricted to the determination of its average chain length, average degree of unsaturation. Measurement of such characteristics is done through both chromatographic and chemical methods of analysis. Chemical methods include the
A.L. ASCANO1 C.V. OPONDA1
1INSTITUTE OF BIOLOGY
UNIVERSITY OF THE PHILIPPINES, DILIMAN, QUEZON CITY, PHILIPPINES
DATE PERFORMED: FEBRUARY 19, 2013
INSTRUCTOR’S NAME: FRANCESCA N. BELTRAN
_____________________________________________________________________________________
ABSTRACT
_____________________________________________________________________________________
INTRODUCTION
Lipids are long aliphatic hydrocarbon chains which are either branched or unbranched that can form rings and may have unsaturation. [8] They are products of animal or vegetable origin which are extracted with either ether, chloroform, benzene, petroleum, carbon disulfide. [6] They can be described as substances which are insoluble in water but soluble in fat solvents. [5] Lipids are compounds that share properties based on their structural similarities mainly a preponderance of nonpolar groups. [4] It includes compounds such as fatty acids, glycerolipids, sphingolipids, terpenes, steroids and carotenoids. [7]
Lipids can be classified as: saponifiable lipids and unsaponifiable lipids. Saponifiable lipids are open-chain compounds containing polar heads and long nonpolar chains. Among the saponifiable lipids are triacylglycerols, waxes, sphingolipids and phospholipids. Unsaponifiable lipids on the other hand are those with fused rung compounds such as steroid and cholesterol. [8]
Molecular weight can be calculated by
MW= (3 x g sample)/(mol KOH) (1)
Lipids of natural origin are usually obtained from their esters by alkaline hydrolysis. Such procedures allow the yield of complex mixtures of fatty acids which are resolvable with relative difficulty. Description of fatty acids therefor is restricted to the determination of its average chain length, average degree of unsaturation. Measurement of such characteristics is done through both chromatographic and chemical methods of analysis. Chemical methods include the
References: [3] Campbell, N. Biology 8th Ed. Pearson Benjamin Cummings Pub: San Francisco. 2008 [4] Campbell, J [5] Gortner, R. Outlines of Biochemistry. J. Wiley & Sons, Inc. 1938 [6] White, A [7]Kuchel, P. Schaum’s Outlines: Biochemistry 3rd Ed. McGraw-Hill Companies: United States of America Inc. 2009. [8]Davenport, J.B., and Johnson A.R., Biochemistry and Methodology of Lipids. John Wiley and Sons, Inc. 1971. [9]Analysis of Lipids [10] Ghatak, K.L. Techniques and Methods in Biology. PHI Learning Private Limited:New Delhi. 2011 [14] Saponification [15] High Quality Sodium Hydroxide and Potassium Hydroxide for Making Soap. http://www.certified-lye.com/lye-soap.html. (accessed Feb 27, 2013). [16] Fatty Acid Composition and Properties of Oils Chart. http://thesoapdish.com/oil-properties-chart.htm (accessed Feb 27, 2013). [17] Lauric Acid. http://www.parchem.com/chemical-supplier-distributor/Lauric-Acid--000314.aspx (accessed Feb 27, 2013).