Isolation and characterization of trichalasin-producing endophytic fungus from Taxus baccata

An endophytic fungus (strain T1) isolated from Taxus baccata was studied for the production of metabolites with anticancer and antioxidant activities. This fungus was identified as Diaporthe sp. based on rDNA-internal transcribed spacer (ITS) sequence analysis. The crude extract showed cytotoxic activity against MCF-7 and HeLa cancer cell lines, with IC50 (concentration inhibiting 50% of growth rate) values of 1058 ± 44 and 1257 ± 80 μg ml−1, respectively. The scavenging activity of fungal extract increased significantly with increasing concentration [IC50 (concentration required to scavenge 50% of free radicals) 482 ± 9 μg ml−1]. Ultra-high-performance liquid chromatography-quadrupole-time of flight analysis revealed the presence of three trichalasins (trichalasin E, F and H) in the crude extract of T1 which are known to have antitumour and antioxidant activities. These results suggest that Diaporthe sp. has the potential to be used for therapeutic purposes because of its antiproliferative and antioxidant potential and also for the production of cytochalasins.