Chemical, Bioactivity, and Biosynthetic Screening of Epiphytic Fungus Zasmidium pseudotsugae

Abstract

We report the first secondary metabolite, 8,8′-bijuglone, obtained from pure cultures of the slow growing Douglas fir- (Pseudotsuga menziesii var. menziesii) foliage-associated fungus Zasmidium pseudotsugae. The quinone was characterized using extensive LC/MS and NMR-based spectroscopic methods. 8,8′-Bijuglone exhibited moderate antibiotic activity against Gram-positive pathogens and weak cytotoxic activity in the NCI-60 cell line panel and in our in-house human colon carcinoma (HCT-116) cell line. An analysis of the fungal genome sequence to assess its metabolic potential was implemented using the bioinformatic tool antiSMASH. In total, 36 putative biosynthetic gene clusters were found with a majority encoding for polyketides (17), followed by non-ribosomal peptides (14), terpenes (2), ribosomal peptides (1), and compounds with mixed biosynthetic origin (2). This study demonstrates that foliage associated fungi of conifers produce antimicrobial metabolites and suggests this guild of fungi may present a rich source of novel molecules.

In Vitro Efficacy of Extracts and Isolated Bioactive Compounds from Ascomycota Fungi in the Treatment of Colorectal Cancer: A Systematic Review

“…In fact, 8,8′-Bijuglone showed an IC 50 value of 45 µg/mL in the HCT-116 cell line. Functional extracts and bioactive compounds from Cladosporium were tested on both CRC and breast cancer cells with a significant differential effect [ 39 , 86 , 87 ]. Taxol was one of the compounds, which, due to its potent antitumor effect, has not only been tested in several clinical trials but has also come to be used in clinics against CRC [ 88 ].…”