Lipids are vital biomolecules available as fats, oils, waxes, and vitamins to man. They have many uses in daily life.
Uses of Lipids in the human body
Lipids are useful for
- Heat generation and Storage of energy
- Synthesis of Hormones
- In cell Signaling
- To Provide Hardness to palms and soles
- Smoothness to the skin
- Formation of cell organelles
- In cellular transport
- Partition of substances
Lipids perform many functions like
Nutrition through Food
- Lipids like edible oils, butter, and fats from plant and diary products are widely used as food products.
- Lipids serve as fuel molecules in the body.
- Frying is a way of cooking where food is immersed in hot edible oils.
- This is both nutritious and also adds to the taste of the food.
- The method helps to cook the food fast and also gives brittleness to the material.
- This is one of the ways by which humans can consume essential fatty acids.
- These edible oils are extracted from groundnut, sunflower, olive, mustard, and other plant seeds.
- The excess carbohydrates in the body are stored as fats in our body.
- This storage occurs in the adipose tissue.
- The fats produce more calories than carbohydrates and protein during the breakdown.
- This is beneficial during starving conditions as the body can generate energy from fats.
- This stored fat is also useful for birds during long migrations.
- The fat in the body breaks down to produce the needed energy for long flights.
- Most of the hormones are made of lipids.
- They are responsible for body homeostasis, sexual characters, delivery, milk formation, etc.
- It is interesting to note that lipid signaling is involved in cell signaling.
- This lipid signaling is found to regulate apoptosis, cell growth and also calcium mobilization.
Hardness to palm and soles
- Lipids are stored in adipose tissue which is present below the skin.
- But this is very thick in the buttocks, palms of hands and soles of the legs.
- These regions have a high level of physical load like sitting, holding, or carrying the body.
- The presence of fat here helps to keep the skin hard, manage friction and also weight.
- Besides this, fat is also present around critical organs in the body like the kidneys. This way it helps to absorb shocks during body movements.
Smoothness to the skin
- The skin of humans is smooth due to the distribution of the fat layer beneath it.
- It is especially attractive in women as it imparts a smooth and soft look to the skin.
- Another benefit of fat beneath the skin is that it minimizes heat loss to the surrounding environment.
- If there is excess heat, the body tries to reduce it by sweating instead.
Formation of cell organelles
- Many cell organelles in animal and plant cells are made of lipids.
- The organelles like the cell membrane, vesicles, mitochondria, endoplasmic reticulum, etc. have lipid membranes.
- Especially the cholesterol, sphingolipids are present in these membranes.
- They provide elasticity, shape, and also the movement of substances through them.
Helps in cellular transport
- Cellular transport from outside to inside and vice versa is tightly controlled.
- This occurs by processes like diffusion, osmosis, etc.
- These processes are controlled by the hydrophilic and lipophilic properties of the cell membrane.
Importance of lipids in industry
- For Better Drug delivery
- Diagnosis of diseases
- Vitamin supplements
- Separation by partition
- Lipids are used to make micelles which help in the delivery of drugs to deeper most tissues in the body.
- The human body can bedivided into two compartments.
- One is the water compartment while the other is the lipid compartment.
- The water compartment includes the bloodstream and other fluids in the body cavities.
- While the lipid compartment includes the brain and other deeper tissues and cells.
- When a drug or a substance is taken, it distributes into these compartments based on its chemistry.
- If the drug is hydrophilic, it distributes into the blood and other fluids but may not reach the brain and other deeper most tissues.
- Similarly, when a lipophilic substance is given, it reaches the brain and other deeper tissues faster.
- Then it starts to come back to the water compartment.
- This phenomenon is widely used in medicine to target drugs.
- This method minimizes the wastage of drugs and other unwanted side effects.
- If a drug has to act on the brain, it is made lipophilic by chemical modification or inserted into miscelles.
- So, when administered, it reaches the brain first and shows its action there.
- Then it comes back to the water compartment and by this time its effects are lowered due to decreased concentration.
Diagnosis of diseases
Presence of lipids in the body like cholesterol, lipoproteins help in the diagnosis of diseases related to the heart.
Lipids like shark liver oil and Cod liver oil are used as medicine.
Mineral oils like liquid paraffin are used as a drug to relieve constipation.
Cosmetics like lipstick, creams, and lotions are made of lipids.
Lipsticks contain a large portion of wax, oil.
While lotions and creams are made of emulsions, emulsions have water dispersed in oil or vice-versa based on the need.
Partition of substances
The lipids are not soluble in water. Any substance having lipids in higher concentrations can act as hydrophobic.
That means they are readily soluble in oils but not in water.
This property has many benefits in the industry for
Extraction is the process of taking of desired product from a mixture.
When plant material is made into a pulp, the active ingredient in it, like the phytoconstituents, can be extracted based on solubility.
Identification of unknown plant material is found, and if it has oil, it can be identified by analysis of the oil constituent.
If the constituent is lipid-based, it can be separated by using its partition property.
Purification of plant and animal tissue extracts is more natural.
The lipid components move into organic solvents like petroleum ether, hexane, etc., making it easy to separate by a separating funnel.