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Aspergillus is a fungal genus that strongly affects health of humans, animals, and plants worldwide. Endophytes are now widely considered as a rich source of bioproducts with potential uses in medicine, agriculture, and bioindustry. Cupressaceae plant family hosts a variety of bioactive ascomycetous endophytes. In this study, antifungal activity of a number of such endophytes were investigated against human pathogenic fungi Aspergillus fumigatus and Aspergillus niger. To this end, 16 superior bioactive endophytic fungi from Cupressaceae were used, including Alternaria alternata, Alternaria pellucida, Ascorhizoctonia sp., Aspergillus fumigatus, Aspergillus niger, Aurobasidium sp., Cladosporium porophorum, Fusarium oxysporum, Penicillium viridicatum, Phoma herbarum, Phoma sp., Pyrenochaeta sp., Trichoderma atroviride, Trichoderma atroviride and Trichoderma koningii. In vitro bioassays indicated anti-Asperilli activity of the endophytic fungi in dual cultures. Most notably, Trichoderma koningii CSE 32 and Trichoderma atroviride JCE 33 showed complete growth inhibition of both A. niger and A. fumigatus, within 3 to 7 days. Also, volatile compouds (VOCs) of T. koningii CSE 32 and T. atroviride JCE 33 exhibited 33-100% growth inhibition of A. niger, whithin 3 days. Moreover, on the day 7, growth of A. niger was less affected than that of A. fumigatus. In general, it appears that there is a direct relationship between the exposure time and the inhibitory activity of endophytes VOCs on the growth of target Aspergillus species. Furthremore, the extracellular secondary metabolites (SMs) of four selected fungal endophytes exhibited anti-Aspergillus activity at all treatment levels as shown by Agar-diffusion assay. SMs from T. koningii CSE 32 and Pyrenochaeta CSE 134 showed strongest activities against A. niger, and SMs from T. koningii CSE 32 and F. oxysporum CAE 14 showed strongest activities against A. fumigatus. In conclusion, given the globally recognized issue of antibiotic resistance and the urge to discover new antimicrobial substances, our findings provide new insights into the potential use of Cupressaceae's endophytic fungi in antifungal-based drug discovery programs., (Copyright © 2020. Published by Elsevier Masson SAS.)

The worldwide commercial production of the oyster mushroom Pleurotus ostreatus is currently threatened by massive attacks of green mold disease. Using an integrated approach to species recognition comprising analyses of morphological and physiological characters and application of the genealogical concordance of multiple phylogenetic markers (internal transcribed spacer 1 [ITS1] and ITS2 sequences; partial sequences of tef1 and chi18-5), we determined that the causal agents of this disease were two genetically closely related, but phenotypically strongly different, species of Trichoderma, which have been recently described as Trichoderma pleurotum and Trichoderma pleuroticola. They belong to the Harzianum clade of Hypocrea/Trichoderma which also includes Trichoderma aggressivum, the causative agent of green mold disease of Agaricus. Both species have been found on cultivated Pleurotus and its substratum in Europe, Iran, and South Korea, but T. pleuroticola has also been isolated from soil and wood in Canada, the United States, Europe, Iran, and New Zealand. T. pleuroticola displays pachybasium-like morphological characteristics typical of its neighbors in the Harzianum clade, whereas T. pleurotum is characterized by a gliocladium-like conidiophore morphology which is uncharacteristic of the Harzianum clade. Phenotype MicroArrays revealed the generally impaired growth of T. pleurotum on numerous carbon sources readily assimilated by T. pleuroticola and T. aggressivum. In contrast, the Phenotype MicroArray profile of T. pleuroticola is very similar to that of T. aggressivum, which is suggestive of a close genetic relationship. In vitro confrontation reactions with Agaricus bisporus revealed that the antagonistic potential of the two new species against this mushroom is perhaps equal to T. aggressivum. The P. ostreatus confrontation assays showed that T. pleuroticola has the highest affinity to overgrow mushroom mycelium among the green mold species. We conclude that the evolutionary pathway of T. pleuroticola could be in parallel to other saprotrophic and mycoparasitic species from the Harzianum clade and that this species poses the highest infection risk for mushroom farms, whereas T. pleurotum could be specialized for an ecological niche connected to components of Pleurotus substrata in cultivation. A DNA BarCode for identification of these species based on ITS1 and ITS2 sequences has been provided and integrated in the main database for Hypocrea/Trichoderma (www.ISTH.info).