We planted 337 aronia plants on school property, in order to be able to learn more about the cultivation and science of this plant in the coming years.

In the following article, the plant and its effects will be further explored. The main information stems from English secondary literature (lit. 1) that was translated into German

Introduction

The aronia shrub belongs to the rose family, as well as the subfamily of pitted fruit. Native to North America, aronia is divided in two genera:

1. Aronia melanocarpa (= black chokeberry or aronia berry)
2. Aronia arbutifolia (= red chokeberry)

The A. melanocarpa is a shrub that can grow from 90 to 180 cm high. It has dark purple berries with diameters of about 6 mm that grow in clusters of eight to 14 on a single red stem. They A. melanocarpa berries ripen and fall off the stems early, in comparison to the berries on the A. arbutifolia plant, which are bright red and stay on the stem through the winter. The green leaves are matte gray and hairy on the underside and change to red in the fall.

A. melanocarpa is native to regions that extend from the northeastern parts of the US as far west as the Great Lakes region and as far south as the upper part of the Appalachian Mountains. There it can be found in mountain bogs and on bare mountains, but does not grow on coastal plains.

Cultivation

The most information about aronia cultivation refers to A. melanocarpa, which contains very valuable ingredients. The berries are used for juice, marmalade and wine production, as well as for natural coloring.

The plant became popular after it was introduced in Russia in the 19th century, originally as berry shrubs in home gardens. The large-scale and commercial cultivation of aronia began in the Soviet Union in the late 1940s. The largest site of aronia cultivation was a 17,800 ha. area in Siberia (1984). Today, aronia is cultivated on a large scale especially in Poland, but also in the Czech Republic, Slovakia, Germany and the Ukraine. The most frequently grown types are "Viking", "Nero" and "Aron", which are used for mass fruit production.

Application

The local North American Potawatomi tribe first used the fruits of the A. melanocarpa in a tea to help fight against a cold. Aronia berries were also used to produce pemmican, a nutritious and durable food made from fat, crushed, dried meat and sometimes fruits. Today, the aronia berries are used due to their high anthocyanins, an ingredient for antioxidant and healthy juices, teas and refreshing liquors. A. melanocarpa's berries have a bitter, sour taste and have an astringent effect, which makes them better suited for processing rather than direct consumption.

In the pharmaceutical industry, aronia extract is used to produce syrups and dietary supplements.

The high content of pectin makes the aronia berry useful in the production of marmalades; they are combined with fruits with low pectin contents. Furthermore, aronia berries or extracts can be added to marmalades in order to improve the taste, color or antioxidant levels. In addition to grapes (Vitis sp.) and roselle plants (Hibiscus sabdariffa), A. melanocarpa berries are an important source of anthocyanins which can be used as a natural food coloring.

Pharmaceutically Relevant Component

Relevant literature indicates that A. melanocarpa berries have especially rich links to pharmaceuticals. Polyphenols, especially anthocyanins and proanthocyanidins, build the main groups of biologically-active components of the aronia fruit. These connections are responsible for the antioxidant properties of the berries. Other phenols include chlorogenic acid, neochlorogenic acid, as well as a small number of tannins.

Some Contents of A. Melanocarpa:

The total phenol content reaches about 2,000 to around 8,000 mg per 100 g of dry weight and depends on the type, the cultivation conditions and the harvest date.

Tab. 2 Contents of A. melanocarpa

The most important and most researched group of pharmaceutically-relevant components of aronia are flavonoids, most of all anthocyanins and proanthocyanidins.

Proanthocyanidins

The primary flavonoid in the aronia berries are proanthocyanidins. Their appearance can reach 0.66% to 5.18% of the dry weight.

Anthocyanins

In aronia fruits, anthocyanins are the second largest group of the phenolic compounds and range in levels of concentration from 0.60% to 2.00% of the dry weight. Anthocyanins appear in aronia as a mixture of cyanidin-glycosides: 3-galactoside, 3-glucoside, 3-arabinoside and 3-xyloside, of which cyanidin 3-galactoside is the most important one. (compare Tab. 3)

Antioxidant Activity

Fruits are rich sources of polyphenol compounds and numerous studies have proven their antioxidant effects. In experiments, scientists have examined how the contents of different fruits 'capture' cell-damaging substances, such as free radicals, thereby rendering them harmless.

One study compares the capacity of different fruits to absorb oxygen radicals. It shows that A. melanocarpa fruits have stronger antioxidant activity than other berries.

Aronia also has stronger antioxidant activity than:

Pharmacological Efficacy

For many years, aronia berries and their products were used primarily as food additives. Their positive effects on human health were not yet established. For example, a drop of aronia juice was frequently used to give blueberry yogurt a deeper color, even if there were not really that many blueberries in it.

Nowadays, more and more food products are coming to market that emphasize aronia's health benefits due, in part, to recent scientific studies. Such studies claim that polyphenols lower the risk of cardiovascular diseases, in addition to having antimutagenic and lipid-lowering properties. Black aronia extracts did not seem to pose any toxicity risks.

Some examples of completed tests:

Anti-mutagenic Effects

In the Ames test, the mutagenic activity of Benzo[a]pyren and 2-Aminofluoren were almost entirely eliminated in the presence of Anthocyanen from aronia berries.

Anti-carcinogenic Effects

The experiment with the human colon tumor HT29-Klon-19A-Cells, performed using microgelelectrophoresis (comet assay), proved that H2O2-DNA strand breaks dramatically decreased in the presence of A. melanocarpa.

At the same time endogenous generations of oxidized DNA-bases stayed unmodified.

Liver Protecting Effects

The liver-protecting effects of A. melanocarpa juice were detected in an experiment on rats with CCl4-induced liver damage. The addition of aronia juice in the rats' feed caused a meaningful reduction in the histopathological changes in the liver.

Anti-diabetic Effects

The anti-diabetic effects were proven for A. melanocarpa fruits as well as leaf extracts. In diabetes research, it is common to use animals and induce them with diabetes through various methods.

Black chokeberry juice, which was administered orally for six weeks, showed a substantial (> 40%) glucose-reducing effect in rats with Streptozocin-diabetes. However, these effects were not detected in healthy rats.

Medicinal Plants in Russia

Due to its high biological activity, the aronia plant is regarded as a medicinal plant in Russia and is used to treat a variety of illnesses, including colds and diseases of the stomach, intestines, glands, liver and gallbladder. Aronia is used for anti-inflammatory and vascular-strengthening purposes. For measles or scarlet fever, the berries are recommended for healing and strengthening the immune system. After it was found that aronia increased the elimination of radioactive strontium, it was also administered in the treatment of radiation poisoning.