Culturable Endophytic Fungi of Atractylodes macrocephala: Influence of Tissue Type and Geographic Location on Their Antifungal, Therapeutic, and Cytotoxic Potentials.

Atractylodes macrocephala Koidz. is a medicinal plant that has been widely used as a tonic agent in different ethno-medical systems in East Asia. This study explores the culturable endophytic fungi of A. macrocephala and potential correlations between these fungi and the active components of this medicinal plant. The antipathogenic activity of these endophytic fungi against three species of pathogenic Fusarium was examined. The cytotoxicity of the endophytic fungi extracts was assessed in five human cancer cell lines. A total of 2338 endophytic fungal isolates were obtained from the root, stem, leaf, and rhizome of A. macrocephala. The endophytic fungal community structure in A. macrocephala was influenced by tissue type and geographical location. Trichothecium roseum (Pers.) Link was found to be closely associated with atractylenolide I, a major active component of A. macrocephala. In total, 40 of the 77 endophytic fungal taxa (51.95%) manifested inhibitory effects on the growth of at least one of the fungal pathogens. In addition, metabolites from most fungal endophytes exhibited cytotoxicity against the cancer cells; in particular, AM450 and AM448 were the most potent (IC₅₀ < 5 μg/mL) against MCF-7, A549, KB, KB-VIN, and MDA-MB-231. These extracts showed potent cytotoxicity against cancer cell lines and warrant further study; toxicity testing on normal cells is needed to assess selectivity and therapeutic potential.