Anthocyanins are natural pigments with properties and benefits for the immune system, such as aiding against inflammation and for the circulatory system. They have uses in the pharmaceutical and food industries. In plants, they develop various functionalities, and in humans, they serve as antioxidants and therapeutic agents.
Contents
What are Anthocyanins
They are a type of secondary metabolite of plants that act as pigment, producing a color change in leaves that can be violet, red, and orange. The darker the plant, the more amount of polyphenolic compounds (flavonoids) it possesses.
In humans, anthocyanins offer various antioxidant properties and serve as protectors of the cardiovascular system.
Anthocyanin is a glucoside of anthocyanidin. Its composition consists of aglycone (anthocyanidin molecule) attached to a sugar. This union is produced through glycosidic bonding.
The meaning or definition of anthocyanin comes from the Greek origin of the words anthos (flower) and the word kyanos (blue). Thus, the compound is named anthocyanin, an antioxidant plant pigment that belongs to the group of polyphenols.
Types of Anthocyanins
Currently, there are more than 300 anthocyanins cataloged and discovered, each of them having a name derived from the plant from which it is obtained or from the vegetable where the anthocyanin was first synthesized.
Despite initially having twenty, according to their chemical structure and bonding with different sugars such as glucose, galactose, rhamnose, arabinose, and xylose, in nature, the number of anthocyanins can reach 150 since there are also unions with sugars such as sophorose, rutinose, and gentiobiose.
Properties of Anthocyanins
They are used for their pharmacological effects, being applied in different treatments and therapies. Because anthocyanins are not broken down by the human digestive tract when ingested, they can easily reach some targets in different vital systems. Something that gives anthocyanin an incalculable value in medicine.
But to know in more detail all their benefits, what they are for, and their possible uses and applications, let’s see all the properties of anthocyanins:
- Memory and cognition enhancers.
- Anti-inflammatory.
- Antitumor.
- Antidiabetic.
- Protectors of the cardiac system.
- Antioxidants.
- Antithrombotic.
- Hypotensive.
For Memory
There is data on the benefits of anthocyanins for memory. When blueberries rich in anthocyanins were administered to treat senile dementia and related cognition problems in elderly individuals, it was observed that there was a better response of neuronal signaling, partly reducing situations where short-term memory disappeared, and habitual tasks ceased to be learned.
The anthocyanins studied for memory are:
- 3-cyanidin galactoside.
- 3-cyanidin glucoside.
- 3-arabinose cyanidin.
- 3-malvidin galactoside.
- 3-delfinidin galactoside.
These have been used in mice from food sources, that is, by providing a diet rich in blueberries (Vaccinium) since this fruit is very rich in flavonoids and polyphenols, antioxidants that make up the parent branch of anthocyanins. Foods can be fresh or lyophilized, dehydrated but retaining all their plant parts and eliminating water.
Properties for Inflammation
Their effects are powerful in reducing the inflammatory process of tissues, facilitating the recovery of muscle injuries as well as participating in the blockade of some inflammatory diseases or those that generate inflammation due to gradual degeneration as occurs in arthritis.
The anti-inflammatory properties of anthocyanins prevent discomfort in various types of human conditions, needing to be taken for a minimum period of 2 weeks for their effects to be noticed in the body.
This point is related to the properties to improve cognition since according to the study «The impact of fruit flavonoids on memory and cognitions,» Dr. K. A. Youdim showed clinical evidence of the effects of anthocyanins to inhibit neuroinflammation, increasing synaptic activity and the arrival of nutrients to the brain. In this study, Youdim also noted how flavonoids are capable of crossing the blood-brain barrier and targeting neurons, releasing them, and protecting them with their antioxidant action.
Anticancer Properties
Their protective function is very high because of their antimutagenic bioflavonoids, enhancing their effects as they are often administered with vitamin C. For cancer prevention, they prevent the deterioration of cellular DNA, preventing damaged cells from appearing that will proceed to duplicate, risking the initiation of tumor formation.
Anthocyanins are used as a chemopreventive agent, combining them with traditional medicinal therapies to counteract the increase of carcinogenic metabolites.
For these purposes, the bioflavonoid quercetin can be used along with cyanidin glucosides (anthocyanins).
For Diabetes
They are indicated to reduce insulin resistance and regulate glucose assimilation in the blood. Anthocyanins for diabetes have been studied by several medical scientists, mentioning here the study conducted by Aedin Cassidy of the University of East Anglia at King’s College London.
According to published data, some types of flavonoids including anthocyanins can reduce the changes occurring in the bodies of diabetic individuals. After several weeks of consuming fruits rich in polyphenolic compounds such as red cabbage, purple carrots, red grapes, and berries, there is less insulin resistance, with the next results being focused on type 2 diabetes patients.
At this point, it was also observed that adiponectin levels improved after several weeks of starting the consumption of flavonoids of the flavone and anthocyanin class.
For Obesity Control
They have the ability to inhibit digestive enzymes alpha-glucosidase, alpha-amylase, lipase, and protease. These enzymes are related to obesity and type 2 diabetes mellitus. The use of anthocyanins for obesity and diabetes can restrict alpha-glucosidase activity, reducing blood glucose levels.
The use of anthocyanin with ellagitannins, hydrolyzable tannins of the polyphenol class, inhibits alpha-amylase enzyme activity. This leads to less fat assimilation from the food consumed during meals. The proanthocyanidins in wine and the grapes from which it is produced inhibit adipocyte formation and the accumulation of adipose tissue in arteries, providing significant benefits in preventing coronary diseases and regulating LDL cholesterol.
For the Immune System
Consuming foods rich in flavonoids and anthocyanins improves the immune system. Fruit and natural juices with blueberries, grapes, and pomegranates increase the production of lymphocytes responsible for the body’s defenses.
This type of immune system cells increases with the presence of proanthocyanidins, improving the prevention of bacterial and viral infections.
To enhance the body’s defenses, you can consume berry fruit juices or eat several pieces of fruit a day, especially Boysenberries (Rubus ursinus x ideaus), grapes, raspberries, and purple vegetables.
Anthocyanins as pH Indicator
Red pigments from plants are generally used as an element to control pH fluctuations. When pH increases, it has an effect on the solution. Anthocyanins, as pH indicators, undergo a quinoidal structure, displaying a purple color. If the solution becomes alkaline, they would change to blue, and in low pH, they turn intense red.
To use them as a pH indicator, they can be obtained using cold extraction methods, often by applying acidified ethanol or methanol. For pigments that are labile and can easily decompose, acetic acid can be applied to prevent decomposition and obtain them in perfect condition.
For this purpose, betalains and chlorophyll can also be used since they are substances sensitive to pH changes. To indicate pH fluctuation with chlorophyll, one must observe the change from dark green to olive green and bright green.
Uses as Dye
There are also applications in the food industry due to their staining power. Anthocyanins as a natural dye function in the production of beverages, but they have some drawbacks such as their low stability. In the presence of ascorbic acid, sugar, and oxygen, they degrade. Also, when there are metals or enzymes that will break them down.
This limits the occasions in which they are employed as a dye. With a pH higher than 4, their chemical stability disappears, losing coloration. To apply them correctly, the pH must remain stable between values ranging from 1 to 3.5.
The origin of colorants with anthocyanins is usually from grape skin, fresh radishes, and red cabbage, although manufacturers choose the food considering their own commercial interests as they can vary depending on the geolocation of the production of compounds with polyphenols. Also, in their logistical interests in worldwide distribution.
Anthocyanins in Foods
While dark or purplish plant foods are a good source of flavonoids and antioxidant compounds, the foods with the highest anthocyanin content are as follows:
| Anthocyanin Content in Foods (mg per 100 g of fresh product) | |
| Food (fruit, plant) | Anthocyanin Content |
| Purple Corn (Zea mays) | 1,642 |
| Aronia Melanocarpa | 1,480 |
| Red and Black Grapes | 888 |
| Eggplant (Solanum melongena) | 750 |
| Black Raspberry (Rubus occidentalis) | 589 |
| Blueberries (Vaccinium) | 558 |
| Raspberry (Rubus idaeus) | 365 |
| Cherries (Prunus cerasus) | between 350 and 400 |
| Açaí Palm (Euterpe oleracea) | 320 |
| Blackberry (Rubus fruticosus) | 317 |
| Red Currant (Ribes rubrum) | between 80 and 420 |
| Black Currant (Ribes nigrum) | between 165 and 412 |
| Oranges (Citrus × sinensis) | 200 |
| Red Wine | between 24 and 35 |
Other foods rich in anthocyanins include red cabbage, purple carrots, red rice, black beans, red onion, oakleaf lettuce, purple and black (Indigo) tomatoes, red cabbage, strawberries, pomegranates, grapes, purple cabbage, and radishes.
To achieve the best anti-inflammatory and antioxidant effects, it’s best to use various plant sources, include several of these products in the diet, and alternate them to complement the intake of other necessary nutrients for their proper utilization and metabolism.
Purple or violet-colored foods, with shades of purple and black, are a very rich source of antioxidant compounds full of flavonoids and polyphenols that help slow down aging and protect the body from various diseases.
How to Take Them
We’ve already indicated that there are two healthy sources to obtain and include them as a therapeutic product or as a dietary supplement, so there are also two ways to take anthocyanins.
- Through food, by consuming fruits and vegetables.
- Through dietary supplements.
The way to take anthocyanins from fruits is very simple. Just select some of the foods we have indicated in the «foods with anthocyanins» section of this article and eat them throughout the day. It is advisable to vary the type of fruit, consuming different varieties and vegetables to enhance their effects and complement them with other nutrients that will promote metabolism and the body’s defenses.
But if you want to access their properties through a dietary supplement, then anthocyanins in capsules should be swallowed at a rate of 1 or 2 capsules per day. Always accompany intake with water or a liquid to help them dissolve better in the stomach.
The ideal time to take these types of flavonoids is during the day. You can accompany their intake with food, although it is not necessary to do so with meals. To avoid stomach upset, it is recommended not to take them on an empty stomach.
Reference
- British Journal of Nutrition of University of Queensland – Poudyal, S. Panchal, and L. Brown.
- Flinders University of Australia coordinated by doctors Izabela Konczak and Wei Zhang 2004 in Journal of Biomedicine and Biotechnology.
- Iowa Women’s Health Study 2007- Exponent Center for Chemical Regulation and Food Safety of Washington (USA) – P. J. Mink
- Nurses Health Study 2011 of American Journal of Clinical Nutrition – A. Cassidy.
- Nurses Health Study II 2012 – A. Jennings 2012 of American Journal of Clinical Nutrition.
- Cancer Prevention Research 2009 – L. S. Wang and G. D. Stoner in Cancer Letters.
- The impact of fruit flavonoids on memory and cognitions 2010 J. P. Spencer in British Journal of Nutrition.
