Absorption and Assimilation of Fats: Properties, Classification, Types

What are Lipids?

Water is a polar molecule. These organic compounds are nonpolar molecules that can only be dissolved in nonpolar solvents. These molecules are produced by the liver in the human body and can be found in some red meats, oil, fried meals, cheese, whole milk and butter.

Properties of Lipids

Fats and oils make up the lipid family of organic substances. These molecules produce a lot of energy and are involved in a variety of bodily activities. Some key features of lipids are listed below.

1. Lipids are important in biological systems because they help to build the cell membrane, which is a mechanical barrier that separates a cell from its surroundings
2. Lipids are a class of chemicals defined by their insolubility in water and solubility in nonpolar solvents
3. Lipids are organic compounds that are high in energy and supply energy for a variety of biological functions
4. Lipids are a diverse collection of chemicals that are mostly made up of hydrocarbon chains
5. Lipids are nonpolar substances that are greasy or oily and are stored in the body’s adipose tissue

Classification of Lipids

Lipids are divided into two groups:

Nonsaponifiable Lipids

Hydrolysis will not be able to break down a non-saponifiable lipid into smaller molecules. Cholesterol and prostaglandins are examples of non-saponifiable lipids.

Saponifiable Lipids

Phospholipids, sphingolipids, triglycerides and waxes are examples of saponifiable lipids, which include one or more ester groups that allow them to hydrolyse in the presence of enzymes, acid, or base.

Polar and nonpolar lipids are two types of lipids that fall within this category.

Triglycerides, a kind of nonpolar lipid, are used as a source of energy as well as a storage medium.

Membranes make use of polar lipids, which can act as a barrier to the external aqueous environment. Glycerophospholipids and sphingolipids belong to the polar lipids category.

All of these lipids need fatty acids to function properly.

Types of Lipids

Steroids, sphingolipids, glycerophospholipids, triglycerides and fatty acids, are only a few of the many forms of lipids that are essential for survival. Complex lipids and simple lipids are the two major categories.

Simple Lipids

Fatty acid esters with different alcohols.

1. Waxes: Monohydric alcohols with higher molecular weight esters of fatty acids.
2. Fatty acid esters with glycerol are known as fats. Oils are fats that are liquid at room temperature.

Complex Lipids

Fatty acid esters are fatty acid esters that contain groups other than alcohol and fatty acid.

1. Glycolipids (glycosphingolipids): are lipids that include carbohydrates sphingosine and fatty acid.
2. Phospholipids: Phospholipids are lipids that include a phosphoric acid residue in addition to alcohol and fatty acids. The alcohol in glycerophospholipids is glycerol, whereas the alcohol in sphingophospholipids is sphingosine. 
3. Other complex lipids: amino lipids and sulfolipids, for example. Lipoproteins fall into this group as well.

Precursor and Derived Lipids

Ketone bodies, fatty aldehydes, Fatty acids, steroids, other alcohols, and glycerol, as well as hydrocarbons, hormones, and lipid-soluble vitamins, are all examples. Cholesteryl esters, cholesterol, and acylglycerols (glycerides) are all classified as neutral lipids since they are uncharged. The hydrolysis of both complex and simple lipids produces these chemicals.

The following sections go through some of the numerous forms of lipids.

Fatty Acids

Fatty acids are carboxylic acids (also known as organic acids) that have lengthy aliphatic tails (long chains) and are either saturated or unsaturated.

Saturated fatty acids

The fatty acid is saturated when there are no carbon-carbon double bonds. Because of their tendency to pack their molecules together and form a straight rod-like structure, saturated fatty acids have greater melting temperatures than unsaturated acids of the same size.

Unsaturated fatty acids

When a fatty acid has more than one double bond, it is classified as unsaturated.

“Natural fatty acids are typically unbranched and have an equal number of carbon atoms.”

Unsaturated fatty acids, on the other hand, have a structural kink that prevents them from forming straight rod-like groups of molecules.

Role of Fats

Fats perform a number of important roles in our bodies. The following are some of the major functions of fats:

• Many fat-soluble vitamins must be connected with fats in order to be efficiently absorbed by the body.
• They give insulation to the body and are an efficient way to store energy for extended periods of time.
• Fats in the right proportions are essential for our bodies to operate properly.

Digestion and Absorption of Lipids

Here is an explanation of digestion and absorption of lipids biochemistry. Lipids are insoluble in water chemical molecules that are made up of fatty acids. Lipids include fats, which are the most prevalent. Digestion and absorption of fats are challenging due to lipids’ insoluble nature.

Fats cling together as a big glob of insoluble substance once they enter the stomach due to their hydrophobic nature. Bile juice, which contains bile salts, aids in the breakdown of the substance. Pancreatic lipase, one of the body’s most important fat-absorbing enzymes, subsequently reacts to these broken molecules.

Fats are broken down by pancreatic lipase into tiny molecules of free monoglycerides and fatty acids, which the small intestine may pass through and into the circulation.

Dietary fats after absorption appear in the circulation as Chylomicron.