Anthocyanin: Structure, Properties, Classification, Source, Uses

A water-soluble pigment found in plants, especially fruits and vegetables. Anthocyanins are responsible for the red, blue and purple pigments in fruits, vegetables and tubers. These pigments belonging to the phenolic group have a glycosylated form. Regarding the meaning of anthocyanin, the word anthocyanin is derived from the combination of anthos and kayanos, the former meaning flower and the latter meaning dark blue.

Most red, blue and purple flowers contain anthocyanins. For example, red hibiscus, red rose, pink flower, blue rosemary, blue chicory, purple sage, purple mint and lavender are edible. Some of these are also commonly used as food, colouring agents and folk medicine.

Anthocyanin-C15H11O6+

Anthocyanins are a subgroup of phenolic phytochemicals. It is mainly found in fruits and flowers, especially in the vacuolar fluid of their epidermal tissue. Since anthocyanins are available as glycosides, they can be called glycones. They are a subset of flavonoids. Therefore, they are polyphenols that give a unique colour to the plant or plant part. Acylated anthocyanins are present in plants also. The structure of anthocyanins is derived from flavylium ions and its main formula is C15H11O6+.

Properties of anthocyanins-C15H11O6+

• They are responsible for the red, blue or purple colors of vegetable petals, seeds such as eggplant, onions, black rice and berries.

• Based on the chemical composition of anthocyanins, they can be divided into two groups: flavonoids and phenolics.

• These plant pigments are water soluble.

• It has been used as an appetite stimulant, anti-inflammatory and to prevent other diseases.

• Since this substance is a bioactive substance, its bioavailability is an important factor in maintaining health and treating some diseases.

Classification of anthocyanins-C15H11O6+

They can be classified into two main groups based on the chemical composition of flavonoids and phenols. Anthocyanins are almost universal, water-soluble pigments of land plants. They are polyhydroxy and polymethoxy glycosides derived from 2-phenylbenzopyrylium or flavylium salts. About 600 types of anthocyanins have been discovered.

In particular, flavonoids are a group of secondary metabolites responsible for the widest colour spectrum in a number of seeds, leaves, fruits and flowers. However, different substitution patterns exist in natural plant species, such as 5-methoxycyanidin, 3-deoxycyanocyanidin, 7-methoxycyanocyanidin, and 6-hydroxycyanidin.

Source of anthocyanins-C15H11O6+

• Fruits, vegetables and grains contain delicious and nutritious anthocyanins. Foods rich in anthocyanins include blackberries, purple asparagus, Concord grapes, pomegranates, eggplants, raspberries, purple corn, red cabbage, and black rice.

• However, anthocyanins are found in fruits and vegetables.

• They are not available alone, but in combination.

• It has also been found to be more effective in combination with other compounds than when taken alone.

• More research is needed to explore the different aspects of anthocyanins.

Uses of anthocyanins-C15H11O6+

Anthocyanins have wide applications-

• Red, blue and purple pigments extracted from plants are widely used as food dyes. For example, anthocyanins extracted from grape skins are often used to add attractive colour to fruit jams, drinks, or sweets.

• Anthocyanin-rich flowers and berries are used as a remedy for a variety of ailments.

• They have various properties such as antimicrobial, anti-cancer, anti-inflammatory, anti-diabetic, anti-obesity, etc. and are also very effective in preventing cardiovascular diseases (CVD).

• Therefore, anthocyanins are potential medicinal substances with excellent medicinal properties.

• The demand for plant colours such as anthocyanins in the food industry is increasing rapidly as people are now concerned about the toxic effects of artificial food colours.

Therapeutic effect

Anthocyanins are known for their therapeutic effects in various diseases like-

Anti-cancer agents: Anthocyanins have been widely studied for cancer treatment and for inhibiting angiogenesis. It helps the growth of cancer cells. The studies of these diseases are specifically based on animal models and laboratory and cellular constructs.

Antidiabetic: Anthocyanins have been widely used in the treatment of diabetes in many studies. For this reason, the consumption of keratoconus has long been prescribed in the traditional treatment of diabetes in China. One study found that consuming anthocyanin-rich fruits at a time for eight weeks led to significant improvement.

Anti-Obesity: Anthocyanins may fight obesity. One study found that including purple corn in a regular diet for 12 weeks not only resulted in weight loss, but also reduced the weight of white and brown adipose tissue.