Flavonoid

Plants have special parts that give them color.

These colors can be red, blue, or yellow. This helps bugs find flowers for food.

These colors also help the plant stay safe. They can block harsh light from the sun. These parts are found in many foods. You can find them in berries and cabbage. They are also in dark chocolate. Even onion skins have them!

These colors make the plant world so bright.

Flavonoids are special parts found in many plants.

The name comes from a word for yellow. This is because they often give plants their bright colors. These colors help flowers attract bugs for pollination.

They also help plants stay safe. They can block harsh light from the sun. They can even help plants fight off pests.

Flavonoids have a specific shape. They are made of 15 carbon atoms. This shape is like a skeleton with three rings. There are many different kinds of flavonoids. Some help make petals look red or blue.

Others are found in many foods we eat. You can find them in blueberries and strawberries. They are in red cabbage and dark chocolate. Even the skin of a peanut has them. Citrus fruits like grapefruit also have them.

Most people eat these every day. In the USA, adults eat about 190 mg per day. Most of this comes from tea or cocoa. Even though we eat them, they are not called nutrients. Our bodies do not need them to grow.

Flavonoids are a large group of natural compounds found in plants. The name comes from the Latin word "flavus," which means yellow. These substances are very important for how plants live and grow.

They act as pigments to give flowers their bright colors. These colors, like red, blue, or yellow, help attract insects for pollination. Flavonoids also help plants stay healthy by blocking harsh ultraviolet light from the sun. They can even help a plant fight off pests or diseases.

To understand how they work, we can look at their tiny shape. A flavonoid is built around a 15-carbon skeleton. This skeleton is made of two rings called phenyl rings and one middle ring called a heterocyclic ring.

Because of this shape, scientists often call them C6-C3-C6 compounds. Depending on how these rings are connected, they form different groups. For example, anthocyanidins help make colors in petals. Other groups, like flavanones, are found in citrus fruits.

Scientists have been studying these compounds for a long time. In the 1930s, a scientist named Albert Szent-Györgyi made a big discovery. He found that vitamin C alone was not the only thing helping people stay healthy. He noticed that extracts from oranges, lemons, or paprika worked even better.

He thought these extra substances were a special kind of vitamin. He even called them "vitamin P." Later, scientists learned these were actually flavonoids, and the name "vitamin P" was no longer used.

There are many places to find flavonoids in the food we eat. You can find them in blackberries, black currants, and red cabbage. They are also in parsley, onions, and blueberries.

Many people get them from drinking black tea or eating dark chocolate. In the United States, adults eat about 190 mg of flavonoids every day. Most of that comes from a group called flavan-3-ols. In the European Union, the average amount is about 140 mg per day.

Even though we eat many flavonoids, they are not called nutrients. This is because our bodies do not need them to grow or stay healthy. Our bodies are also not very good at using them. Less than 5% of the flavonoids we eat are actually absorbed into our blood. Most of them are broken down in the stomach or liver and then leave the body quickly.

Because they leave so fast, they do not have a big effect on our health. They are still a very interesting part of the plant world.

Flavonoids are a massive group of plant compounds called polyphenolic secondary metabolites. The name comes from the Latin word "flavus," which means yellow. These substances are found in many different types of plants across the world. They are essential for plant survival and biological processes.

While humans consume many flavonoids through food, they are not classified as nutrients. This is because they do not provide calories or influence growth and development. They also do not have established effects on preventing human diseases. Scientists study them to understand how plants interact with their environments.

To understand their chemistry, we must look at their unique molecular structure. Every flavonoid is built upon a 15-carbon skeleton. This structure consists of two phenyl rings, known as rings A and B. These are connected by a middle heterocyclic ring, called ring C, which contains an oxygen atom.

Because of this specific arrangement, scientists often use the abbreviation C6-C3-C6. This shorthand describes the two six-carbon rings connected by a three-carbon chain. The exact shape and properties change based on how these carbons are arranged. This chemical variety allows for thousands of different flavonoid compounds to exist.

Flavonoids perform several vital roles to help plants live and thrive. They act as important pigments that create colors in flower petals. These colors, such as red, blue, or yellow, attract pollinating insects.

They also provide antioxidant protection against ultraviolet light from the sun. This helps protect the plant's cells from damage. Additionally, flavonoids can act as chemical messengers to regulate cell growth. They even help plants defend themselves against pathogens and environmental stresses. Some flavonoids can even inhibit the growth of organisms that cause diseases.

One fascinating process involves the relationship between plants and soil bacteria. Certain flavonoids are secreted from the roots of host plants, such as legumes. Legumes include common plants like peas, beans, clover, and soy.

When bacteria called Rhizobia live in the soil, they can sense these flavonoids. This chemical signal triggers the bacteria to secrete something called Nod factors. The host plant then recognizes these factors and begins a symbiotic relationship. This process can lead to the formation of root nodules on the plant. This interaction is a key part of how nitrogen is fixed in the soil.

Chemists classify flavonoids into several distinct subgroups based on their structures. One group is the anthocyanidins, which use a flavylium ion skeleton.

Another major group is the anthoxanthins, which include flavones and flavonols.

There are also flavanones and flavanonols, which have different functional groups.

Another important category is the isoflavonoids, which are derived from a different chemical structure. Finally, there are neoflavonoids, which come from a 4-phenylcoumarin structure. These different shapes determine how each compound behaves in nature.

The study of these compounds has a notable history in science. In the 1930s, Albert Szent-Györgyi and other researchers made an important observation. They found that vitamin C alone was not as effective at preventing scurvy as extracts from oranges or lemons. They believed other substances in the fruit were providing extra help. They called these substances "citrin" or "vitamin P."

Later research showed that these substances, like hesperidin, did not meet the official criteria to be called vitamins. Therefore, the term "vitamin P" is now considered obsolete in science.

Humans consume a wide variety of flavonoids through many different foods. You can find them in blackberries, black currants, and red cabbage. They are also abundant in citrus fruits, blueberries, and dark chocolate.

In the United States, the average adult consumes about 190 mg of flavonoids per day. Most of this intake comes from flavan-3-ols, often found in tea or cocoa. In the European Union, the average intake is about 140 mg per day.

Despite this, the body absorbs less than 5% of these compounds. They are quickly metabolized in the liver and excreted from the body.