Amaryllidaceae Alkaloids Inhibit the Growth of Endophytic Fungi

The chemoecological role of the Amaryllidaceae alkaloids, accumulated in plants from the Amarylli¬doideae subfamily (Amaryllidaceae), is poorly studied. These alkaloids are known for their potent pharma¬cological activities, including anti-acetylcholinesterase (AChE), anti-tumoral, anti-microbial, anti-viral and cytotoxic. In the present work, the ability of some Amaryllidaceae alklaloids to inhibit the growth of endo¬phytic fungi was studied. A total of 115 endophytic fungal strains were isolated from Leucojum aestivum L. growing in geographycally distinct locations. Sixty-five stains, able to grow in laboratory conditions, were identified and classified into 31 species belonging to 11 phylogenetically diverse genera. The fungal species of genera Fusarium, Trichoderma and Talaromyces were predominant. The endophyte species and genera patterns were found to be different among the L. aestivum L. populations and plant organs. Galanthamine, epi -norgalanthamine and lycorine, as well as alkaloid fractions and extracts consisting of homolycorine-, haemanthamine-, tazettine- and Sceletium -type alkaloids as main components exhibited different growth inhibitory effects depending on fungal strain. An extract from Narcissus cv. Hawera, consisting of Scele¬tium -type alkaloids, showed the most effective and broad-spectrum inhibitory activity against the tested endophytic strains. The results indicate that the Amaryllidaceae alkaloids may play a role in the plant-en¬dophyte interactions.