Saponifiable Lipids

The ester functional group includes saponifiable lipids. They’re made up of long-chain carboxylic (of fatty) acids linked to an alcoholic functional group through an ester bond that may be saponified. On the basis of catalysed ester hydrolysis, fatty acids are liberated. 

Triacylglycerides, glycerophospholipids, and sphingolipids are the most saponifiable lipids.
Esters that can be saponified (hydrolysis under basic circumstances) are present (waxes, triglycerides, phospho-glycerides, sphingolipids)

Structure:

The function of lipids is determined by their structure. The highly insoluble triacylglycerols, for example, are utilised as the body’s primary chemical energy storage form. The Cs in the acyl-chains of the triacylglyceride are in a greatly reduced form, in contrast to polysaccharides like glycogen (a polymer of glucose). The primary source of energy for not just our bodies but also our civilization comes from the oxidation of carbon-based compounds to carbon dioxide and water, which is a highly exergonic and exothermic process.

 Because each carbon is partly oxidised, sugars are already halfway along the free energy spectrum. The full oxidation of lipids can provide 9 kcal/mol, compared to 4.5 kcal/mol from proteins or carbs. 

 As a result, storing the same amount of energy in carbohydrates as triacylglycerides, which are kept as anhydrous lipid “drops” within cells, would need three times the weight. The reminder of this lipids unit will focus on fatty acids and phospholipids, as well as the structures they form in aqueous solution, rather than triacylglycerides, which are primarily used for energy storage.

Extraction: 

Saponifiable lipids (SLs) were extracted with hexane from the microalga Nannochloropsis gaditana wet biomass (86 H20%) in order to convert them into fatty acid methyl esters (FAMEs, biodiesel). At low temperatures (20-22 °C), the effect of homogenization pressure on SL extraction yield was investigated. The SL extraction yield was doubled after homogenization at 1700 bar. 

Two biomass batches were employed, each with a varied lipidic makeup but a similar total lipid concentration. Batch 1 had lower levels of SLs (12.0 wt%) and neutral saponifiable lipids (NSLs, 7.9%) than batch 2. (21.6 and 17.2 water %respectively). 

Batch 2 had a high SL yield (69.1 wt percent) and purity (71.0 wt percent) as a result of this, as well as the selectivity of hexane toward NSLs. 

Examples:

Triacylglycerides, glycerophospholipids, and sphingolipids are some of the most saponifiable lipids. The backbone of the first two is glycerol. Three fatty acids are esterified to the three OHs on glycerol in triacylglycerides. Two fatty acids are esterified at carbons 1 and 2, while a phospho-X group is esterified at carbon 3.

Saponification:

Saponification is an organic chemical process in which an alkali is used to break down an ester into a carboxylic acid and alcohol. This reaction is most commonly used in the creation of soap goods, as we’ll see shortly. Functional groups include the phrases ester, carboxylic acid, and alcohol. In a chemical, a functional group is essentially a collection of molecules or atoms that can be easily identified.

Reaction and Mechanism in Mechanics:

Saponification includes two primary players ester and alkali. One of the products is a carboxylate ion, which should be noted. This is a carboxylic acid with a negative charge after the proton has been removed. Use this ion as an identification marker to see if you’re dealing with a saponification process.
Saponification Equation in General
When we examine the mechanism, or instruction manual, for this reaction, steps that must be followed. 

These steps are outlined below:

Step 1: The alkali molecule’s hydroxide ion swoops in and nucleophilically attacks the ester or fatty molecule. The word nucleophile should not frighten you. It simply denotes a molecule that will establish a chemical bond as a result of its attraction to electrons in another atom or molecule.
The Saponification Process Continues with Step 2 Reaction: Following Step 1, the OR group becomes a departing group. The oxygen atom coupled to R is denoted by OR, which is a placeholder for any molecule or atom. The OR group, desperate to get out, leaves, causing a double connection to form. This results in the formation of a carbonyl group. Because it has a carboxylic acid functional group, this novel compound may appear familiar.

Step 3: Unable to leave the proton (H) in carboxylic acid alone, the OR group extracts it. Deprotonation is the process of eliminating a proton from a molecule. The final products, carboxylate and alcohol, are generated after deprotonation.

Value of Saponification:

The number of milligrams of potassium hydroxide (KOH) necessary to saponify one gramme of fat under a certain situation is known as the saponification value (SV) or saponification number (SN). The saponification value is an important criterion for determining and evaluating the quality of edible fats and oils. The saponification number also indicates the average molecular weight of the fatty acids. The smaller the molecular weight of all fatty acids, the higher the number.
mg KOH/g is the unit of measurement.

Saponification’s Applications:

Saponification is most commonly used in the production of soaps. Soaps are available for a variety of functions, including washing, cleaning, and lubricating. Soaps can be precipitated by adding saturated sodium chloride to them. Saponification can also be used in conjunction with fire extinguishers. It’s used in fire extinguishers to turn flammable fats and oils into non-combustible soap, which helps to put out the fire.
Saponification is particularly important in the food business since it allows you to determine how much free fatty acid is contained in a product. The amount of alkali given to the fat or oil to neutralise it can be used to determine the amount of free fatty acid.

Conclusion:

 Saponification is a chemical reaction that produces glycerol and a fatty acid salt dubbed “soap” when triglycerides are treated with sodium or potassium hydroxide (lye).
When sodium hydroxide is applied, it produces a hard soap.
Saponification produces soaps with a variety of characteristics. As a result, they are divided into two categories: hard and soft soaps. Because of the alkali employed in their synthesis, the soaps in these categories are frequently distinct from one another. Hard soaps are ones that contain NaOH as a main ingredient. In hard water, which contains magnesium and calcium ions, hard soaps are also beneficial. Soft soaps are made from potassium hydroxide (KOH).