What are Anthocyanins? Classification and Applications

Anthocyanins

Anthocyanins are another name for anthocyans.  It refers to the water-soluble hues found in plants, particularly fruits and vegetables. Anthocyanins are responsible for fruits, vegetables, and plants’ blue, red, and violet colors. When it comes to the anthocyanin definition, the term ‘Anthocyanins’ is derived from the Greek words ‘Anthos’ and ‘Kyanous.’ The former connotes flowers, and the latter connotes a dark blue color.

Anthocyanins are found in most red, blue, and purple flowers. Red hibiscus, red roses, pink bloom, blue juniper, blue chicory, purple mint, sages, and lavender, for instance, are safe to eat. Some of these are used as food, dyes, and folk medicine.

So, how would you define anthocyanin? It is important to understand what is anthocyanin, its structure, and its physical properties.

What is Anthocyanin?

Anthocyanin definition is easy to remember! It is defined as a kind of phenolic extract. It is typically found in fruits and flowers, notably in the vacuolar sap of their epidermal layers. Because anthocyanin is present as a glycoside, it is also known as glycine. They are a kind of flavonoid. Thus, polyphenols give plants or sections of plants their distinct color. Acylated Anthocyanins are found in plants in addition to conventional anthocyanins.

Anthocyanin Structure and Formula

The anthocyanin structure is derived from the flavylium ion, and its fundamental chemical formula is C₁₅H₁₁O+.

Anthocyanin is the popular term for flavonoids that disperse readily in water. Their fundamental structural unit is 2-phenylchromenylium (flavylium), which connects hydroxyl (-OH) and/or methoxyl (-OCH₃) groups, as well as one or more sugars. As per the diverse substituent groups on the flavylium B-ring, they exist in organic ingredients, primarily in a form associated with glucose, galactose, and rhamnose, and may be categorized into at least six common varieties, such as pelargonidin, delphinidin, cyanidin, malvidin, petunidin, and peonidin. According to the findings, the ortho-dihydroxy phenyl structure on the B-ring is the active location that suppresses tumor development and metastasis. Anthocyanidins are sugar-free molecules.

Flavylium Cation

Various anthocyanidins have been characterized depending on the proportion and location of hydroxyl and methoxyl groups, and six of these are widely found in plants and fruits:

• pelargonidin
• petunidin
• peonidin
• delphinidin
• cyanidin
• malvidin

Anthocyanins

Anthocyanins, like the majority of other flavonoids, are found in plant and soil foods as glycosides, which are connected to one or more sugar molecules.

These are the most prevalent carbohydrates found in natural pigments:

• Glucose, the most common
• Fructose
• Galactose
• Xylose
• Arabinose
• Rhamnose

Sugars are mostly connected to the C3 position as 3-monoglycosides. They are linked to the C3 and C5 positions as diglycosides (with the attainable forms: 3,5-diglycosides, 3-diglycosides and 3-diglycoside-5-monoglycosides). Glycosylations were also discovered at C7, C3′ and C5′ locations.

Furthermore, anthocyanins include several acylated sugars in the structure; these anthocyanins are also known as polyglycosides.

More than 500 distinct anthocyanins have been found based on 31 anthocyanidins. These different anthocyanins are determined by the nature of hydroxylation, methoxylation, and glycosylation processes. The various groups attached to the sugar units also play a role in the classification process.

• 30 percent of these 31 monomers are derived from cyanidin,
• 22 percent from delphinidin,
• and 18 percent from pelargonidin.

Methylated variants of cyanidin, delphinidin, and pelargonidin, known as peonidin, malvidin, and petunidin, account for 20% of anthocyanins.

As a result, up to 90% of the most common anthocyanins are linked to delphinidin, pelargonidin, cyanidin, and their methylation derivatives.

Properties of Anthocyanins

They are important for the red, blue, and violet hues of vegetable leaves, grains such as aubergine, onions, black rice, and blueberries. Together with carotenoids, the concentration of anthocyanins influences the color of fall leaves.

They are divided into two classes depending on their anthocyanin chemistry: flavonoids and phenolics. These substances are water-soluble.

It has been prescribed to stimulate hunger as a choleric drug and to avoid various ailments. Because this is a bioactive component, bioavailability is critical for maintaining good health and mending a variety of ailments.

Potential Benefits of Anthocyanins 

• Impacts on bacteria: Delphinidin, an anthocyanin pigment, may aid in the defense against Staphylococcus aureus bacterial infections, according to a test-tube study (1Trusted Source).  

• Sun protection: The pigments may protect your skin from UVB rays, according to tests conducted in test tubes (1Trusted Source).  
• losing weight: According to a study done on women, those who consumed meals high in anthocyanin had much less body and belly fat than those who had diets low in this substance (32Trusted Source). 

Health Benefits of Anthocyanins 

• It has antioxidant qualities, which means they protect against dangerous substances called free radicals.  
•  Oxidative stress is brought on by free radical buildup in the body. Your chance of developing chronic conditions like cancer and heart disease may rise as a result of this oxidative stress, which also causes inflammation (3Trusted Source, 4Trusted Source).  
• Thus, antioxidants aid in lowering oxidative stress and the risk of disease. 

Other Benefits, 

It might lessen inflammation  

It may also aid in reducing inflammation (3Trusted Source, 4Trusted Source).  

potential defense against type 2 diabetes  

Regular consumption of foods high in anthocyanins may protect against type 2 diabetes. 

Reduces the risks of cancer  

Flavonoids, a type of antioxidant thought to have potent anti-cancer properties, include anthocyanins (14Trusted Source, 15Trusted Source).   

Classification of Anthocyanins

They are divided into two classes based on their chemical composition: flavonoids and phenolics. Anthocyanins are virtually ubiquitous, water-soluble pigments found in terrestrial plants. They are polyhydroxy and polymethoxy glycosides produced from 2-phenylbenzopyrylium or flavylium salts. There are around 600 different anthocyanin entities known.

Flavonoids are a type of secondary metabolite responsible for the most diverse color range in the number of seeds, leaves, fruits, and flowers. Other tissues are classified as phenylpropanoids. Plant species with diverse substitution patterns, such as 7-methoxycyanthocyanidins, 5-methoxycyanthocyanidins, 3-deoxyanthocyanidins, and 6-hydroxyanthocyanidins, exist naturally.

Sources of Anthocyanins

Anthocyanin-rich fruits, vegetables, and grains are both tasty and healthy. Anthocyanin-rich foods include:

• Mulberries: ~700 mg
• Black currants: ~300 mg
• Black beans: ~10 mg
• Black grapes: ~30 mg
• Blackberries: ~100 mg
• Strawberries: ~44 mg
• Blueberries: ~20 mg
• Red raspberries: ~30 mg
• Red wine: ~10 mg
• Red onions: ~7 mg
• Red currants: ~10 mg
• Plums: ~25 mg

Still, anthocyanins are present in different fresh produce and green leafy vegetables; however, they are only available in the combined form, not separately. And it has been discovered that the benefits are significantly better when ingested in conjunction with other chemicals rather than in isolation. More study is needed to investigate the many characteristics of Anthocyanins.

Anthocyanin Applications

Anthocyanins have several uses:

• Red, blue, and purple pigments produced from plants are commonly employed as dyes or food colorants. For example, anthocyanin derived from grape skin is often used to provide appealing colors to fruit jams, drinks, and confectionaries.
• Various anthocyanin-rich flora and fruits are used to cure a variety of diseases. They have antimicrobial, anti-cancer, anti-inflammatory, anti-diabetic, and anti-obesity effects. They are also very beneficial in preventing cardiovascular disease (CVDs). As a result, anthocyanins are prospective pharmacological components with high medical value.
• Because people are concerned about the toxicity of synthetic food pigments, the food sector is seeing a surge in the popularity of plant-based colorants such as anthocyanins.

The Function of pH

The pH of the vacuole where these compounds are kept influences their hue, which ranges from

• red in highly acidic conditions to
• purple-blue in intermediate pH levels to
• yellow-green in alkaline settings.

In conjunction with pH, the degree of hydrogenation or methylation pattern of the A and B rings and the glycosylation pattern can influence the hue of these flavonoids.

Finally, the color of some plant pigments is caused by complexes formed by anthocyanins, flavones, and metal ions.

Because of the alterations in chemical composition that occur in reaction to pH changes, anthocyanins are frequently utilized as pH monitors.

Conclusion

Anthocyanins, also known as anthocyans, are water-soluble vacuolar pigments that can look red, violet, indigo, or black based on their pH. For the first time, in 1835, the German chemist Ludwig Clamor Marquart gave the term Anthocyanin to an active component that gives flowers a blue hue. Anthocyanin-rich foods include blueberries, raspberries, black rice, and soybeans. Anthocyanins are responsible for some of the hues found in fall leaves.

Anthocyanins are members of the flavonoids family derived via the biosynthetic pathway. They can be found in all higher plant tissues, including leaves, stems, roots, petals, and fruits. Anthocyanins are created by combining anthocyanidins with carbohydrates. They have no odor and are somewhat bitter.

Although allowed in the European Union to color meals and beverages, anthocyanins are not authorized to be used as a food supplement since they have not been proven safe when utilized as dietary supplement components.

Frequently Asked Questions

Q1. Is it safe for everyone to consume anthocyanin dietary supplements?

Anthocyanins have been shown to benefit general health since they include many minerals and antioxidants. Still, the researchers couldn’t conclude if a high quantity of anthocyanins is beneficial for treating certain health disorders.

The dietary supplements have not been tested for safety. As a result, the content may change somewhat from what is stated on the product label. Furthermore, no actual experiment was conducted to determine the safety of the supplements for pregnant women, breastfeeding moms, youngsters, and those using medications.

Q2. What is Anthocyanin and what is its role in the prevention of Cardiovascular Diseases (CVDs)?

Anthocyanins are the most often eaten flavonoids, and they are responsible for the vibrant colors seen in fruits, vegetables, flowers, and grains. However, in addition to bringing color to your meal, they provide several health advantages. They assist in protecting liver injury, lowering blood pressure, improving vision, preventing cardiovascular disease, and many other things.

Anthocyanin’s anti-oxidative characteristics play a significant role in CVD prevention. They work on the cells that cause atherosclerosis to form. Anthocyanins also aid in lowering systolic blood pressure and arterial pressure, which can lead to cardiac problems such as heart attack.

Q3. Are anthocyanins water soluble, and do they degrade when heated?

Anthocyanins are a kind of plant pigment that is abundant. They are water-soluble and belong to the flavonoid family. There are almost 500 distinct anthocyanins known. Plants, flowers, and fruits get their vibrant hues from these pigments, which range from pink to red, purple, and blue. Anthocyanins and antioxidant activity decreased according to a first-order kinetic model at temperatures ranging from 120 °C to 180 °C.