Glycoside

Glycosides are a carbohydrate biomolecule that are found in many types of plants, which do not all use them the same way. For example, some plants use glycosides to store energy, while others use them to store toxins, releasing them to stop herbivores from consuming the plant. Many of these glycosides are in a plant’s flowers.

Medical researchers have learned to harvest glycosides from plants to make new medicines. When taken from plants, engineered, and ingested by humans, glycosides have a variety of effects on the body. Some make it more difficult for the body to ingest simple sugars and carbohydrates, which is helpful for treating Type 2 diabetes. Other glycosides help strengthen the muscles of the heart, reducing the effects of long-term heart failure.

All glycosides include a chemical bond between a glucose molecule and a hydroxy compound. When the two are paired, plants can store the larger molecule without activating the sugar or the chemical. When the chemical is needed, a specialized enzyme breaks the bond between the sugar the hydroxy compound, releasing both.

Background

Atoms are the smallest identifiable units that a pure substance can be divided into while still retaining its chemical properties and characteristics. Atoms are composed of various types of subatomic particles that allow them to bond with one another. These include a positively charged nucleus and negatively charged electrons.

Atoms can form various types of bonds, combining to create molecules. Different molecules utilize different types of bonds, which gives them new properties. Common molecules include water, nitrogen, and ozone. Some molecules organize themselves into rigid structures, creating substances that are difficult to separate or reshape. Others organize themselves into looser formations, allowing the resulting creation to freely change shape.

Molecular bonds can be divided into three types: ionic bonds, covalent bonds, and metallic bonds. Ionic bonds are formed with electrons and transferred from one atom to another. Substances created through ionic bonds are usually hard, but brittle. They also tend to have high melting points, requiring large amounts of energy to break the bonds between molecules.

Covalent bonds are created when an electron becomes shared by two or more atoms instead of being exchanged. These bonds often result in the creation of polymer structures, which are long chains of covalently bonded atoms. Though compounds created through covalent bonds often have low melting points, they are otherwise stable, powerful bonds.

Metallic bonds occur when the electrons surrounding atoms are not associated with any one atom and instead form a cloud. Metallic bonds create substances with unusually strong thermal and electrical conductivity. These substances are usually both solid and malleable, allowing them to be shaped into many useful tools. Most naturally occurring materials are not purely comprised of ionic, covalent, or metallic bonds. Instead, they are predominantly composed of one of the three types of molecular bonds in addition to a few other bonds.

Overview

Glycosides are specialized biomolecules comprised of a glucose entity bonded to an aglycon. Biomolecules are substances that are naturally produced by the cells of living organisms. Though many types of biomolecules exist, they can be broken down into four large categories: carbohydrates, lipids, nucleic acids, and proteins. All biomolecules perform important functions in the bodies of the organisms in which they are found. For example, nucleic acids are responsible for creating the DNA and RNA within organisms, allowing for genetic traits to be inherited, interpreted, and passed down between generations. Proteins are the major structural elements of cells, while lipids and carbohydrates serve as specialized energy stores.

Glycosides are part of the larger carbohydrate grouping of biomolecules. They occur whenever a sugar molecule or uronic acid molecule is combined with a hydroxy compound, most commonly non-sugars called aglycons. Glycosides are an important biochemical in the structure of many plants. They allow plants to store chemicals as inactive glycosides, later releasing them when the glycoside is activated. This process is carried out by specialized enzymes, which deconstruct the glycoside, separating the sugar portion and the non-sugar chemical. Many such glycosides are in the flowers of plants.

Some plants use glycosides to defend themselves against predators. These plants store toxic chemicals as part of a glycoside by bonding them to a sugar molecule for storage. When the plant feels threatened, it uses enzymes to remove the attached sugar molecule and release the toxins, deterring continued consumption by herbivores. Other glycosides serve as antioxidants, chemical transport, and germination.

Scientists have worked to isolate glycosides within plant structures, sometimes locating chemical compounds that are used in the creation of medicines. Cardiac glycosides, such as digoxin, digitalis, and digitoxin, are isolated from the foxglove plant. These chemicals are used to assist people who are struggling with heart conditions. They stop the cell membranes from removing sodium, allowing more calcium to build up in the cells of the heart. This results in stronger heart contractions, improving the function of weakening heart muscles and reducing the effects of heart failure. They can also interact with the atrioventricular node, slowing down a patient’s heart rate. These medications are normally taken orally, in the form of tablets, capsules, or liquids.

Glycosides can also be used to treat non-cardiac illnesses. Some glycosides, such as the alpha-glucosidase inhibitor acarbose, reduce the amount of complex carbohydrates in the intestines. This can reduce the speed at which simple sugars and dietary carbohydrates are absorbed by the blood stream, which is often helpful in the treatment of type-2 diabetes. Other glycosides can be used to treat Gaucher disease, a buildup of fatty substances in one or more organs.

Bibliography

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