While learning about carbohydrates we learnt about “chitin”, which I found to be a very interesting substance.
What is chitin?
Chitin is a long-chain polysaccharide that serves as an armor or cell wall for fungi andarthropods, including all crustaceans and insects. Less famously, it is used for the radula (teeth) of mollusks, and the beak of cephalopods such as squid and octopi. Chitin is a stronger version of keratin, fibrous structural proteins used by reptiles, birds, amphibians and mammals. In some animals such as crustaceans, the shell may be a combination of this substance and keratin. Its molecular formula is (C8H13O5N) n.
Chitin is a polysaccharide found in the outer skeleton of insects, crabs, shrimps, and lobsters and in the internal structures of other invertebrates. Chitin is composed of ß(1-4) linked units of the amino sugar N-acetyl-glucosamine, and is the main source of production of chitosan.
How is chitin formed?
Chemically, chitin is a polysaccharide. A polysaccharide is a polymer — a large molecule consisting of smaller (and in this case, sugar) molecules strung together. Chitin can be processed into many derivatives, the most readily available being chitosan, which is formed when chitin is heated with a chemical solution. Chitosan has some advantages over chitin because it is more water-soluble.
Chemical Structure if chitin.
Where is chitin found?
Chitin is found in the central position to the body plan of arthropods. Arthropod exoskeletons are made of this substance. Instead of growing gradually, like most other animals, arthropods grow in quick stages. When an arthropod grows too big for its exoskeleton, it sheds it in a process called molting. It has less than an hour to grow until its new underlying exoskeleton hardens and becomes incapable of growing any further. This molting process may be repeated dozens of times until the animal reaches its maximum size and eventually dies. As arthropods are among the world’s most successful animal groups, with millions of unique species, we can tell that chitin is a quite useful building material for animal bodies.
The exoskeletons of most arthropods are not actually pure chitin, but consist of this material embedded in a hard protein matrix. The difference between modified and unmodified chitin can be seen by observing caterpillars (unmodified) and beetles (modified). The beetle exoskeleton is more durable. In other arthropods, such as some mollusks and crustaceans, the substance is combined with calcium carbonate to create a much stronger shell.
What are the applications of chitin?
1. Medical uses-Chitin and Wounds
One of the more important things that chitin, and its products, could be used for is in treating burn patients. Chitin has a remarkable compatibility with living tissue, and has been looked at for its ability to increase the healing of wounds. Chitin itself is the subject of exciting medical experiments. When applied to human wounds and surgical cloths, it accelerates the skin healing process. An acidic mixture of chitin, when applied to burns, also accelerates the healing process. Left on for a few days, it can heal a third-degree bun completely. It has been shown to support the immune system during certain kinds of illness-blocking procedures.
Other medical uses for chitin include anti-bacterial sponges and hospital dressings, artificial blood vessels, contact lenses, tumor inhibition, dental plaque inhibition, and blood cholesterol control. Household products include sponges, diapers, feminine napkins, and tampons.
Chitin is used to make medical/surgical thread.
2. Water Treatment
Water Purification — As a polymer, chitosan’s natural tendency is to form long chains of molecules with positive charges, which act like hooks. These natural hooks catch organic materials, such as oils, detergents, and other contaminants suspended in water. The material then coagulates to form flakes that are easily filtered out. Filtration companies are using chitin in clarifiers to help filter particulates and chemicals from water.
3. Dietary Supplements
Chitosan has properties similar to plant fiber and can significantly bind fat, acting like a sponge in the digestive tract. It is not digestible itself and the bound fat leaves via the body without ever entering the bloodstream.
Make-up powder; nail polish; moisturizers; face, hand, and body creams; and toothpaste are just a few consumer products that might contain chitin.
Seeds treated with chitosan are larger and stronger and more resistant to fungal diseases. Treating seeds with chitin can increase crop yields by up to 50%.Chitin is added to commercial feed mixtures containing whey, a by-product of the cheese industry. Many animals find it hard to digest the high-lactose whey. But chitin supports the growth of beneficial microorganisms in the animals’ digestive tract — these bacteria produce enzymes that help the animals digest whey.