Plant Fungal Endophytes as a Source of Biologically Active Substances

The review focuses on endophytic fungi, whose mycelium colonizes living plants without visible manifestation. They are also found in all other kingdoms of eukaryotes. It is noted that the cultivation of fungal endophytes can reduce the load on the harvested medicinal plant resources. The concept of “endophytes” and their types, the history of discovery, classification, approaches to taxonomic identification, the possibility of independent existence in the form of fruiting bodies outside plants, endophytic fungal communities in one plant, distribution in groups of plants and their parts are briefly characterized. The ecological aspects of interaction with plants are considered in more detail – types of beneficial effects for plants and endophytic fungi, the variety of substances formed by cultures of fungal endophytes, and their biological activity. It is shown that in certain cases, substances considered to be active constituents of medicinal plants are formed by endophytic fungi living within them. In many cases, they also form substances with various types of activity that have not been previously isolated from plants.