Definition Of Carbohydrates, Sources And Function

CARBOHYDRATE

Carbohydrates are bio-molecules consisting of carbon (c), Hydrogen (H) and Oxygen (O) atoms with the ratio 2:1 just as in water. Carbohydrates perform numerous moles in living organism, they are found in  natural and processed foods. Carbohydrates are refers to any food that is rich in the complex carbohydrate starch such as cereals, bread, and pasta or simple carbohydrate such as sugar found in candy, juices, and jams. It can also includes chemical compounds such as acetic or lactic acid which are not normally considered as carbohydrates. Dietary fiber are carbohydrates but does not contribute to food energy (kilocalories) in humans but it is often included in the calculation of total nutrients taken by a person. Fibers are not digestible and absorbable. They only plays a very vital role in the gastro intestinal tract system to control bowel movements. 

Carbohydrates



SOURCES OF CARBORHYDRATE
  •  Cereals and grains such as rice, corn, sorghum, Hungary rice (acha), finger millet (tamka) millet
  • Root & tubers such as yam, potatoes, water yam, cocoyam, sweet potatoes. Processed carbohydrates such as pasta (macaroni, noodles, spaghetti) carbonates sugary drinks such colas, juices such fruits juices and sweeten vegetables juices, jams syrups etc.

The body can break carbohydrates down into glucose. It helps in muscles contraction, It helps in  temperature maintenance, regulating heart beat and digestion of foods.


FUNCTIONS OF CARBOHYDRATE

1. Provides glucose as energy production.

2. It stored energy (glucose)

3. Building macro molecules

4. Assisting in lipid metabolism

5. Sparing protein (glucose synthesized from amino acids)


TYPES OF CARBOHYDRATE

Carbohydrates are classified into four types which are monosaccharaides, disaccharides, oligosaccharides and polysaccharides. Carbohydrates are formed by green plant during the process of photosynthesis from carbon dioxide and water.


MONOSACCHARIDE


Are simple sugars  they are the simplest carbohydrates that cannot be hydrolyzed into another simpler form. Examples of monosaccharaides are glucose, fructose, galactose and mannose.


GLUCOSE:- Are naturally found in foods such as corn, root, cereals, honey, dried fruits, fruits juices, fresh fruits etc. These are healthy foods if consume in moderation as part of an adequate diet. Glucose are considered natural sugars when consumed directly from whole foods such as dates.


FRUCTOSE:- Are sugar naturally found in fruits are sweetest and more soluble than glucose. They are founds in fruits such as apples, dates, peers, mangoes, oranges, watermelon.  Can also be found in some vegetables such as asparagus, mushroom, pepper. Fructose are crystalline monosaccharide.


GALACTOSE:- Are groups of simple sugar [monosaccharaides] it chemical formula is C6H12O6. It is usually found in nature combining with other sugars such as lactose, sugar found in milk galactose are less soluble and less sweet than glucose. Mammals that produce milk biosynthesize lactose from galactose  and glucose. galactose  are white, crystalline, water soluble hexose sugar. It similar to glucose in structure but differs in the position of one hydroxyl group.


MANNOSE:- Is a group of monosaccharide that belongs to the groups of aldoses. Mannose occurs in microbes, plants and animals free mannose are found is small amount in some fruits such as oranges, apples, and also in mammalians plasma.

 

DISSACCHARIDES


Disaccharides which is also called double sugar is the sugar formed by the combinations of two monosaccharaides [simple sugar] they are soluble in water. The most common disaccharides are sucrose, lactose and maltose.


SUROSE:- It is the most widely available and used disaccharides, commonly through as the table sugar and naturally occurring sweetness. Is a sugar composed of glucose and fructose subunits produced naturally in plants and it’s the main constituents of white sugar sucrose have the formula C12H22O11.


LACTOSE: Is a disaccharides with the molecular formula C12H22O11 is a sugar composed of galactose and glucose submits. Lactose comes from the lac meaning milk in Latin. Lactose is one of the component of milk which makes up to 2-8% of milk. Examples of lactose rich foods are milk, cheese, yoghurt, milk, chocolates, ice creams, butter etc. No lactose in fruits and vegetable.


MALTOSE:- Is a sugar of disaccharides consisting of two glucose units. Maltose is form when starches like potatoes or rice are broken in the gastro intestinal tract system after digestion. It is then broken down into simpler sugar for energy. Maltose is gotten mostly from cooked foods. Maltose is a very important source of energy that can be stored or used immediately by the body after absorption. it has the  formula C12H22O11. The two units of glucose to form maltose are joined by an abound. Maltose is also referred to as malt sugar examples are cooked potatoes, rice, breakfast, cereals, bread, beer, cornmeal, wheat, barley, Hungary rice, sorghum finger millet.


POLYSSACCHARIDES [COMPLEX CARBOHYDRATES]


Polysaccharides are long chains of monosaccharide [simple sugars] linked by glycosides bonds examples of polysaccharides are starch, glycogens and cellulose. They are made of molecules of smaller   monosaccharide. Polysaccharide can be homo polysaccharide, in which all monosaccharaides  binds together are the same or a heterotopy saccharides where all monosaccharide binds together are different. Straight chain of monosaccharaides  are called linear polysaccharides while branch chain are called branched polysaccharides.

STARCH AND GLYCOGEN:- Glycogen and starch are produced by plants and animals they are the most storage polysaccharides. Starch is a polysaccharides comprising glucose monomers. The simplest form of starch is the linear polysaccharides. Starch is the mixture of two polymers amylase and amylopectin. 10 – 30% amylase and 70 – 90% amylopectin are found in natural starch. It is the most important source of energy source for humans. Starch are metabolized into glucose as energy so if there  is excess glucose it stored in the liver as glycogen examples of starch are cereals, seeds, tubers [potatoes, yam, cocoyam cassava] roots, [carrots] and some fruits [green banana] plantains.

GLYCOGEN: Is a substance deposited in the body tissues in form of carbohydrates. Glycogen is a polysaccharides that forms glucose on hydrolysis. Glycogen are stored in liver and skeletal muscles and small amounts in the brain glycogen is an important energy store for the body for future used. Liver glycogen regulates blood sugar levels and homeostasis while muscle glycogen plays a role in contraction of skeletal muscle for all physical activities in the body. Glycogen as starch is a complex carbohydrates [polysaccharides] at store excess glucose it is also referred to as ‘animal starch’ the constituent of amylopectin in plant starch is similar to the composition and structure of the constituents of glycogen when the body needs energy glycogen is broken down into glucose with glucagon the process is called glycogenolysis.

CELLULOSE: Is a polysaccharides made of chairs of glucose that constitutes the part of the cell walls of plant is an insoluble substance of plant cells walls and of vegetable. Fibers it is made up of linear chain of b[1-4] linked D glucose units cellulose provides straight and rigidity to plant cells the formula of cellulose is [C6H10O5] it is odorless and has no taste cellulose serves as the plants cytoskeleton.

OLIGOSACHARIDES

The formation of two, three or more monosaccharaides join together by O-glycosides bonds. Any carbohydrates in rare cases it gives up to ten units of simple sugar [monosaccharaides]. A saccharides is the units structure of carbohydrates it is smaller than polysaccharides which comprised of more than 10 saccharides units.


CLASSIFICATIONS OF OLIGOSACCHARIDES


  • TRISACCHARIDES: These are oligosaccharides that comprised of three monosaccharaides
  • TETRASACCHARDIES: They are oligosaccharides that comprised four monosaccharides.
  • PENTASCCHARIDES: Comprised five monosaccharaides units
  • ITEXASACCHARIDES: Contains seven monosaccharaides units.
  • OCTASACCHARIDES: Comprised eight monosaccharaides units
  • NONASACCHARIDES: Have nine no saccharides units
  • DECASSACHARIDES: Contains ten monosaccharaides units


Examples oligosaccharides are sucrose lactose and maltose

Post a Comment

Previous Post Next Post