Terpenoid

Plants make many special things. These things can be scents. They can also be bright colors.

Some things give cinnamon its taste. Others make tomatoes look red. They also make sunflowers look yellow.

These parts help the plants stay safe. They can also help plants talk to others.

Some of these things float into the air. They can make the sky look blue. This happens in big mountains.

Nature is full of these amazing bits. Do you smell them in the woods?

Plants make many special things. We call these terpenoids. They come from a small part called isoprene. There are about 80,000 different kinds. They make up 60% of natural products.

Terpenoids give plants many traits. They make eucalyptus smell strong. They give cinnamon and ginger their taste. They also make colors. They make sunflowers yellow and tomatoes red.

These parts help plants stay safe. They can stop germs from growing. They can also call for help. They attract predators to eat bugs that hurt plants.

Some terpenoids are used in medicine. Scientists study them to make new drugs. Animals also make them. Animals use them to make steroids.

Terpenoids can float into the air. When they do, they change. They can turn into tiny bits in the sky. These bits can make haze. This can even change how mountains look. In the Blue Ridge Mountains, trees make the air look blue. This happens when they let out terpenoids.

Sunflowers use these to show yellow color.

Tomatoes use them to look red.

Terpenoids are a huge group of natural chemicals. Some people also call them isoprenoids. They come from a small 5-carbon part called isoprene. Terpenoids are special because they often have oxygen in them. When you add them to terpenes, they make about 80,000 different compounds. They are the largest group of plant secondary metabolites. This means they make up about 60% of all known natural products.

These chemicals work in many different ways. Plants use them to make smells and tastes. For example, they give eucalyptus its scent. They also give cinnamon, cloves, and ginger their flavors. Terpenoids even create colors in nature. They make sunflowers look yellow and tomatoes look red. They can also help plants defend themselves. They act as a shield against germs. They can even call for help by attracting predators to eat hungry bugs.

Scientists group these chemicals by how many isoprene units they have. A hemiterpenoid has only one unit. A monoterpenoid has two units and includes things like menthol or camphor. Sesquiterpenoids have three units. Diterpenoids have four units and include things like ginkgolides. Sesterterpenoids have five units. Triterpenoids have six units and include sterols. Finally, tetraterpenoids have eight units. Carotenoids are a type of terpene derivative called a tetraterpenoid.

Many famous names are actually terpenoids. You might know menthol or camphor. There is also salvinorin A found in the plant Salvia divinorum. Scientists study ginkgolide and bilobalide from the Ginkgo biloba tree. Even the cannabinoids in cannabis are terpenoids. Animals use these building blocks too. Animals produce steroids and sterols from terpenoid precursors.

Terpenoids can even change the way the sky looks. Trees release these chemicals into the air. Once in the air, they turn into new species. These new bits can dissolve into water droplets. This helps create haze or aerosols in the sky. This process can change the color of mountains. The Blue Ridge Mountains in the U.S. look blue from far away. The Blue Mountains in Australia also look blue. This happens because trees put the blue color in the air.

Terpenoids, also known as isoprenoids, are a massive class of naturally occurring organic chemicals. They are derived from a small five-carbon compound called isoprene. While people sometimes use the word "terpenes" to describe the same thing, terpenoids are technically different. Terpenoids contain additional functional groups, which usually means they include oxygen atoms. When you combine these terpenoids with hydrocarbon terpenes, they form about 80,000 different compounds. This makes them the largest class of plant secondary metabolites. In fact, they represent about 60% of all known natural products found in nature.

These chemicals are built through specific biological processes. They often arise through a process called hydrolysis. This happens when water reacts with certain intermediate molecules. For example, terpenoids containing an alcohol group often come from the hydrolysis of carbocationic intermediates. These intermediates are produced from a molecule called geranyl pyrophosphate. Other types follow a similar pattern. Hydrolysis of intermediates from farnesyl pyrophosphate creates sesquiterpenoids. Meanwhile, hydrolysis from geranylgeranyl pyrophosphate results in diterpenoids. This step-by-step chemical building allows for incredible variety.

Scientists classify terpenoids based on how many isoprene units they contain. This determines their size and structure. Hemiterpenoids are the smallest, containing only one isoprene unit and five carbon atoms. Monoterpenoids have two units and ten carbon atoms, including substances like menthol and camphor. Sesquiterpenoids contain three units and fifteen carbon atoms. Diterpenoids consist of four units and twenty carbon atoms, such as ginkgolides. Sesterterpenoids have five units and twenty-five carbon atoms. Triterpenoids contain six units and thirty carbon atoms, which includes sterols. Tetraterpenoids have eight units and forty carbon atoms. Carotenoids are a specific type of tetraterpenoid derivative.

Beyond their size, terpenoids can also be classified by their shape. They can form different types of cyclic structures. These structures might be linear or acyclic, meaning they do not form rings. They can also be monocyclic, meaning they have one ring. Some are more complex, forming bicyclic, tricyclic, tetracyclic, or pentacyclic structures. Some even form macrocyclic structures, which are very large rings. To identify if terpenoids are present in a sample, scientists can use a specific method called the Salkowski test.

Terpenoids serve many vital roles in the natural world. In plants, they act as a defense system called prophylaxis against pathogens. They can also act as attractants. For instance, they might call in predators to eat herbivores that are attacking the plant. Plants also use them for their aromatic qualities. They provide the scent of eucalyptus and the flavors of cinnamon, cloves, and ginger. They even create colors, such as the yellow in sunflowers and the red in tomatoes. In animals, terpenoid precursors are used to biologically produce steroids and sterols.

Many well-known substances are actually terpenoids. This includes citral, menthol, and camphor. There is also salvinorin A, which is found in the plant Salvia divinorum. Scientists study ginkgolide and bilobalide from the Ginkgo biloba tree. Even the cannabinoids found in cannabis are terpenoids. In some cases, terpenoids are added to proteins through a process called isoprenylation. This process helps the proteins attach more easily to cell membranes.

Terpenoids even have a significant impact on the atmosphere. When trees release these chemicals, they enter the air and undergo changes. They are converted into various species like aldehydes, organic nitrates, epoxides, and hydroperoxides. This conversion is driven by short-lived free radicals, such as the hydroxyl radical, and also by ozone. These new species can dissolve into water droplets. This process contributes to the formation of aerosols and haze. This is why the Blue Ridge Mountains in the U.S. and the Blue Mountains in Australia appear blue from a distance. The trees essentially put the blue color into the atmosphere through their terpenoids.