Production of bioactive natural substances by using endophytic fungi

In recent years, many of the current drugs used to treat microbial diseases have become increasingly ineffective due to the emergence of microbial resistance on a global scale. Therefore, there is a constant need to find new and effective compounds that can help mitigate antimicrobial resistance. Secondary metabolites of endophytic fungi, which have great potential to produce new bioactive compounds, have wide ranging antimicrobial activities in this field. Recent studies have shown that endophytic fungi can produce the same or similar bioactive metabolites synthesized by their host plant when cultured outside the plant. Within the scope of the thesis studies, the plant material taken from Betula pendula Roth tree as a source of endophytic fungi was brought to the laboratory under appropriate conditions and endophytic fungi were isolated and purified. DNA extraction was performed from 11 morphologically different endophytic fungi, ITS regions were amplified by PCR and taxonomic species determinations were made. In addition, the isolated fungi were grown on appropriate media and secondary metabolites were obtained by extracting the culture media with appropriate solvent on certain days. Antimicrobial and antioxidant activity assays were performed to determine the bioactivity of the total extracts obtained. In the extracts in which the presence of metabolites was determined by TLC, metabolite determination was also performed by chromatographic methods.