Colors, scents and flavors in nature (e.g. in flowers and fruits) are often caused by so-called secondary plant substances. The term “secondary” does not at all refer to the meaning “secondary”. On the contrary: the bioactive substances, which are usually found in lower concentrations, can have a variety of interesting, positive effects – in contrast to carbohydrates, fats and proteins (primary plant substances). The flora makes use of these to protect itself, for example, from environmental toxins, UV radiation, animals (protection against predation) or infections caused by bacteria, viruses and fungi. It is estimated that there are around 100,000 different bioactive substances, which can be divided into different groups according to their chemical structure. These include, for example, the sulphur-containing “pungent substances” (glucosinolates) found in broccoli, horseradish and cress. Other representatives, such as terpenes, are responsible for the aroma of herbs and the scent of citrus fruits, for example. Apricots, carrots and tomatoes, on the other hand, get their bright colors from carotenoids, the “parasols” of the plant world. Saponins, on the other hand, are soap-like substances that are found in legumes, for example, and make life difficult for potential plant pests. However, the “stars” among the secondary plant substances are undoubtedly the polyphenols. This largest group of bioactive substances is also known as the “vitamins of the 21st century”. Although they are not counted among the well-known, classic vitamins, they are considered to have a “vitamin-like” character. In fact, a large number of health-promoting effects have been proven for polyphenols to date and these biomolecules are now highly valued in terms of their nutritional and physiological importance. Polyphenols are found in fruits such as citrus fruits, in vegetables such as onions or cabbage and in drinks such as green tea. However, the interesting polyphenols are particularly abundant in berries such as elderberries, blueberries, blackcurrants and chokeberries. They give these power fruits their intense color and protect them, for example, from the sun and the resulting free radicals, which can also cause damage to humans – or from attack by bacteria and viruses, which can impair plant growth. The black elderberry (Sambucus nigra L.) has a particularly high anthocyanin content. These are among the most interesting polyphenols. The berries also contain other polyphenols such as phenolic acids and various flavonoids as well as immunomodulatory polysaccharides (especially arabinogalactans). Elderberries are also a good source of B vitamins (especially folic acid) and minerals such as potassium. It is this spectrum of ingredients that is thought to be responsible for the health-promoting effects of the medicinal plant, which was already noted and mentioned by Hippocrates.