A novel species and a new combination of Daldinia from Ban Hua Thung community forest in the northern part of Thailand

During a survey of Xylariales in northern Thailand, several specimens with affinities to the genus Daldinia were found and examined for morphological characters, secondary metabolites, and molecular phylogenetic traits. Aside from morphological and chemotaxonomic studies, a multi-locus phylogenetic analysis using internal transcribed spacers regions (ITS) and the large subunit (LSU) of the ribosomal DNA, the second largest subunit of the RNA polymerase (RPB2), and beta-tubulin (TUB2) genes was performed. Among the specimens was a new species and a new record of a species that had previously never been sequenced and studied for its anamorphic morphology. This species, previously described by Ju and Rogers as Hypoxylon kretzschmarioides based on a single record from Indonesia, showed secondary metabolite profiles reminiscent of those of the genus Daldinia and even clustered in the latter genus in the phylogenetic tree. Therefore, it is transferred to Daldinia as D. kretzschmarioides comb. nov. A second new species, D. subvernicosa sp. nov., was found to have a close relationship with D. vernicosa based on morphological and molecular evidence, but differs from D. vernicosa by long-stipitate asci with mostly subglobose ascospores, and the basal ascospores are often elongated

Three novel species and a new record of Daldinia (Hypoxylaceae) from Thailand

n an investigation of stromatic Xylariales in Thailand, several specimens of Daldinia were discovered. Three novel species (D. flavogranulata, D. phadaengensis, and D. chiangdaoensis) were recognized from a molecular phylogeny based on concatenated ITS, LSU, RPB2, and TUB2 sequence data, combined with morphological characters and secondary metabolite profiles based on high performance liquid chromatography coupled to diode array detection and mass spectrometry (HPLC-MS). The major components detected were cytochalasins (in D. flavogranulata and D. chiangdaoensis) and daldinin type azaphilones (in D. phadaengensis). In addition, D. brachysperma, which had hitherto only been reported from America, was found for the first time in Asia. Its phylogenetic affinities were studied, confirming previous suspicions from morphological comparisons that the species is closely related to D. eschscholtzii and D. bambusicola, both common in Thailand. Daldinia flavogranulata, one of the new taxa, was found to be closely related to the same taxa. The other two novel species, D. phadaengensis and D. chiangdaoensis, share characters with D. korfii and D. kretzschmarioides, respectively.National Science and Technology Development Agenc

Phylogenetic and chemotaxonomic studies confirm the affinities of Stromatoneurospora phoenix to the Coprophilous xylariaceae

The genus Stromatoneurospora was erected in 1973 by Jong and Davis to accommodate the pyrophilic pyrenomycete Sphaeria phoenix and has traditionally been placed in the family Xylariaceae based on morphological features. However, no living culture of this genus has so far been available in the public domain. Molecular data were restricted to an internal transcribed spacer (ITS) sequence that only confirmed the familial position, and was generated from a strain that is not deposited in a public culture collection. We have recently collected fresh material and were able to culture this fungus from Thailand. The secondary metabolites of this strains were analysed after fermentation in multiple media. The the prominent components of these fermentation were purified, using preparative chromatography. Aside from two new eremophilane sesquiterpenoids named phoenixilanes A-B (1-2), four other components that are known from species of the xylariaceous genera Xylaria and Poronia were identified by spectral methods (nuclear magnetic resonance spectroscopy and high resolution mass spectrometry). Notably, (-)-(R)-6-hydroxy-3-methyl-4-dihydroisocoumarin-5-carboxylic acid (6) has not been reported as a natural product before. Moreover, DNA sequences of Stromatoneurospora phoenix clustered with members of the genera Poronia and Podosordaria in a multi-locus molecular phylogeny. These results confirmed that the genus belongs to the same evolutionary lineage as the coprophilic Xylariaceae. The results also suggest that this lineage has evolved independently from the plant-inhabiting saprotrophs and endophytes that are closely related to the genus Xylaria. These findings are discussed in relation to some theories about the endophytic vs. the pyrophilic/coprophilic fungal life style.Horizon 202

The Effect of Cytochalasans on the Actin Cytoskeleton of Eukaryotic Cells and Preliminary Structure–Activity Relationships

In our ongoing search for new bioactive fungal metabolites, two new cytochalasans were isolated from stromata of the hypoxylaceous ascomycete Hypoxylon fragiforme. Their structures were elucidated via high-resolution mass spectrometry (HR-MS) and nuclear magnetic resonance (NMR) spectroscopy. Together with 23 additional cytochalasans isolated from ascomata and mycelial cultures of different Ascomycota, they were tested on their ability to disrupt the actin cytoskeleton of mammal cells in a preliminary structure⁻activity relationship study. Out of all structural features, the presence of hydroxyl group at the C7 and C18 residues, as well as their stereochemistry, were determined as important factors affecting the potential to disrupt the actin cytoskeleton. Moreover, reversibility of the actin disrupting effects was tested, revealing no direct correlations between potency and reversibility in the tested compound group. Since the diverse bioactivity of cytochalasans is interesting for various applications in eukaryotes, the exact effect on eukaryotic cells will need to be determined, e.g., by follow-up studies involving medicinal chemistry and by inclusion of additional natural cytochalasans. The results are also discussed in relation to previous studies in the literature, including a recent report on the anti-Biofilm activities of essentially the same panel of compounds against the pathogenic bacterium, Staphylococcus aureus

Cytochalasans Act as Inhibitors of Biofilm Formation of <i>Staphylococcus aureus</i>

During the course of our ongoing work to discover new inhibitors of biofilm formation of Staphylococcus aureus from fungal sources, we observed biofilm inhibition by cytochalasans isolated from cultures of the ascomycete Hypoxylon fragiforme for the first time. Two new compounds were purified by a bioassay-guided fractionation procedure; their structures were elucidated subsequently by nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry (HR-MS). This unexpected finding prompted us to test further cytochalasans from other fungi and from commercial sources for comparison. Out of 21 cytochalasans, 13 showed significant inhibition of Staphylococcus aureus biofilm formation at subtoxic levels. These findings indicate the potential of cytochalasans as biofilm inhibitors for the first time, also because the minimum inhibitory concentrations (MIC) are independent of the anti-biofilm activities. However, cytochalasans are known to be inhibitors of actin, making some of them very toxic for eukaryotic cells. Since the chemical structures of the tested compounds were rather diverse, the inclusion of additional derivatives, as well as the evaluation of their selectivity against mammalian cells vs. the bacterium, will be necessary as next step in order to develop structure-activity relationships and identify the optimal candidates for development of an anti-biofilm agent

Fungal diversity notes 253-366: taxonomic and phylogenetic contributions to fungal taxa

Notes on 113 fungal taxa are compiled in this paper, including 11 new genera, 89 new species, one new subspecies, three new combinations and seven reference specimens. A wide geographic and taxonomic range of fungal taxa are detailed. In the Ascomycota the new genera Angustospora (Testudinaceae), Camporesia (Xylariaceae), Clematidis, Crassiparies (Pleosporales genera incertae sedis), Farasanispora, Longiostiolum (Pleosporales genera incertae sedis), Multilocularia (Parabambusicolaceae), Neophaeocryptopus (Dothideaceae), Parameliola (Pleosporales genera incertae sedis), and Towyspora (Lentitheciaceae) are introduced. Newly introduced species are Angustospora nilensis, Aniptodera aquibella, Annulohypoxylon albidiscum, Astrocystis thailandica, Camporesia sambuci, Clematidis italica, Colletotrichum menispermi, C. quinquefoliae, Comoclathris pimpinellae, Crassiparies quadrisporus, Cytospora salicicola, Diatrype thailandica, Dothiorella rhamni, Durotheca macrostroma, Farasanispora avicenniae, Halorosellinia rhizophorae, Humicola koreana, Hypoxylon lilloi, Kirschsteiniothelia tectonae, Lindgomyces okinawaensis, Longiostiolum tectonae, Lophiostoma pseudoarmatisporum, Moelleriella phukhiaoensis, M. pongdueatensis, Mucoharknessia anthoxanthi, Multilocularia bambusae, Multiseptospora thysanolaenae, Neophaeocryptopus cytisi, Ocellularia arachchigei, O. ratnapurensis, Ochronectria thailandica, Ophiocordyceps karstii, Parameliola acaciae, P. dimocarpi, Parastagonospora cumpignensis, Pseudodidymosphaeria phlei, Polyplosphaeria thailandica, Pseudolachnella brevifusiformis, Psiloglonium macrosporum, Rhabdodiscus albodenticulatus, Rosellinia chiangmaiensis, Saccothecium rubi, Seimatosporium pseudocornii, S. pseudorosae, Sigarispora ononidis and Towyspora aestuari. New combinations are provided for Eutiarosporella dactylidis (sexual morph described and illustrated) and Pseudocamarosporium pini. Descriptions, illustrations and/or reference specimens are designated for Aposphaeria corallinolutea, Cryptovalsa ampelina, Dothiorella vidmadera, Ophiocordyceps formosana, Petrakia echinata, Phragmoporthe conformis and Pseudocamarosporium pini. The new species of Basidiomycota are Agaricus coccyginus, A. luteofibrillosus, Amanita atrobrunnea, A. digitosa, A. gleocystidiosa, A. pyriformis, A. strobilipes, Bondarzewia tibetica, Cortinarius albosericeus, C. badioflavidus, C. dentigratus, C. duboisensis, C. fragrantissimus, C. roseobasilis, C. vinaceobrunneus, C. vinaceogrisescens, C. wahkiacus, Cyanoboletus hymenoglutinosus, Fomitiporia atlantica, F. subtilissima, Ganoderma wuzhishanensis, Inonotus shoreicola, Lactifluus armeniacus, L. ramipilosus, Leccinum indoaurantiacum, Musumecia alpina, M. sardoa, Russula amethystina subp. tengii and R. wangii are introduced. Descriptions, illustrations, notes and / or reference specimens are designated for Clarkeinda trachodes, Dentocorticium ussuricum, Galzinia longibasidia, Lentinus stuppeus and Leptocorticium tenellum. The other new genera, species new combinations are Anaeromyces robustus, Neocallimastix californiae and Piromyces finnis from Neocallimastigomycota, Phytophthora estuarina, P. rhizophorae, Salispina, S. intermedia, S. lobata and S. spinosa from Oomycota, and Absidia stercoraria, Gongronella orasabula, Mortierella calciphila, Mucor caatinguensis, M. koreanus, M. merdicola and Rhizopus koreanus in Zygomycota