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• This is the first report of endophytic Biscogniauxia in Dendrobium species • Biscogniauxia dendrobii sp. nov. is introduced based on the large discrepancy on both sequences (5.2%) and size of conidia. • The ethyl acetate crude extract of the isolate B. petrensis showed moderate and strong cytotoxic activity against A549 and K562 using CCK8 assay (IC 50 of it 13.5 and 3.5 ug/ml, respectively). Biscogniauxia belongs to the family Graphostromataceae , and species have been found mainly as pathogens in dicotyledonous plants worldwide. Two endophytic strains, Biscogniauxia dendrobii sp. nov. and B. petrensis were isolated from Dendrobium aphyllum and D. harveyanum sampled from southwestern China and northern Thailand respectively. The conidiophores and conidia were used for morphological examination. The maximum likelihood and Bayesian analysis with ITS, TUB2, RPB 2 and LSU sequence data were combined for phylogenetic analyses and species identification. Biscogniauxia dendrobii sp. nov. is introduced based on the large DNA base pair differences (5.2%) and size of conidia. Another known species B. petrensis is also illustrated and described in this study to facilitate species identification on D. harveyanum. The ethyl acetate crude extracts of the isolate B. petrensis showed moderate and strong cytotoxic activity against A549 and K562 using the CCK8 assay (IC 50 of it 13.5 and 3.5 ug/ml respectively). This is the first report of endophytic Biscogniauxia in Dendrobium species and of their cytotoxicity to A549 and K562, all of which enhances the current knowledge on the genus Biscogniauxia. [ABSTRACT FROM AUTHOR]

During our investigation of palm fungi in Thailand, two interesting taxa from Elaeis guineensis and Metroxylon sagu (Arecaceae) were collected. Based on phylogenetic analyses of a combined dataset of ITS, LSU, rpb2, and tub2 nucleotide sequences as well as unique morphological characteristics, we introduce the new genus Haploanthostomella within Xylariales, and a new species Endocalyx metroxyli. Additionally, in our study, the genus Endocalyx is transferred to the family Cainiaceae based on its brown conidia and molecular phylogenetic evidence. [ABSTRACT FROM AUTHOR]

During the course of our search for novel biologically active metabolites from tropical fungi, we are using chemotaxonomic and taxonomic methodology for the preselection of interesting materials. Recently, three previously undescribed benzo[j]fluoranthenes (1−3) together with the known derivatives truncatones A and C (4, 5) were isolated from the stromata of the recently described species Annulohypoxylon viridistratum collected in Thailand. Their chemical structures were elucidated by means of spectral methods, including nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry (HR-MS). The new compounds, for which we propose the trivial names viridistratins A−C, exhibited weak-to-moderate antimicrobial and cytotoxic activities in cell-based assays. [ABSTRACT FROM AUTHOR]