Anthostomella-like fungi on bamboo: four new genera belonging to a new family Pallidoperidiaceae (Xylariales).

This study investigates the phylogeny and taxonomy of Anthostomella-like fungi (Xylariales, Sordariomycetes) found in association with bamboo in Japan. Four new genera, Amphigermslita (including three new species, i.e., A. deformis, A. fusiformis, and A. pseudofusiformis), monotypic Crassipseudostroma (C. phyllostachydis) and Minuticlypeus (M. discosporus), and Pallidoperidium (two new species, P. exasperatum and P. paraexasperatum), and one known genus, Nigropunctata (one new species, N. complanata) are recognized and described. These five genera were found to constitute a distinct monophyletic lineage based on molecular phylogenetic analyses utilizing sequences of ITS and LSU nrDNA, rpb2, and tef1-α sequences. A new family, Pallidoperidiaceae, is proposed to accommodate these bambusicolous Anthostomella-like fungi. The identification of this lineage contributes to our understanding of the evolutionary relationships and classification of these bambusicolous fungi. It suggests that these five genera share a unique evolutionary history and possess shared morphological and ecological characteristics.

Identification of Rosellinia species as producers of cyclodepsipeptide PF1022 A and resurrection of the genus Dematophora as inferred from polythetic taxonomy.

Rosellinia (Xylariaceae) is a large, cosmopolitan genus comprising over 130 species that have been defined based mainly on the morphology of their sexual morphs. The genus comprises both lignicolous and saprotrophic species that are frequently isolated as endophytes from healthy host plants, and important plant pathogens. In order to evaluate the utility of molecular phylogeny and secondary metabolite profiling to achieve a better basis for their classification, a set of strains was selected for a multi-locus phylogeny inferred from a combination of the sequences of the internal transcribed spacer region (ITS), the large subunit (LSU) of the nuclear rDNA, beta-tubulin (TUB2) and the second largest subunit of the RNA polymerase II (RPB2). Concurrently, various strains were surveyed for production of secondary metabolites. Metabolite profiling relied on methods with high performance liquid chromatography with diode array and mass spectrometric detection (HPLC-DAD/MS) as well as preparative isolation of the major components after re-fermentation followed by structure elucidation using nuclear magnetic resonance (NMR) spectroscopy and high resolution mass spectrometry (HR-MS). Two new and nine known isopimarane diterpenoids were identified during our mycochemical studies of two selected Dematophora strains and the metabolites were tested for biological activity. In addition, the nematicidal cyclodepsipeptide PF1022 A was purified and identified from a culture of Rosellinia corticium, which is the first time that this endophyte-derived drug precursor has been identified unambiguously from an ascospore-derived isolate of a Rosellinia species. While the results of this first HPLC profiling were largely inconclusive regarding the utility of secondary metabolites as genus-specific chemotaxonomic markers, the phylogeny clearly showed that species featuring a dematophora-like asexual morph were included in a well-defined clade, for which the genus Dematophora is resurrected. Dematophora now comprises all previously known important plant pathogens in the genus such as D. arcuata, D. bunodes, D. necatrix and D. pepo, while Rosellinia s. str. comprises those species that are known to have a geniculosporium-like or nodulisporium-like asexual morph, or where the asexual morph remains unknown. The extensive morphological studies of L.E. Petrini served as a basis to transfer several further species from Rosellinia to Dematophora, based on the morphology of their asexual morphs. However, most species of Rosellinia and allies still need to be recollected in fresh state, cultured, and studied for their morphology and their phylogenetic affinities before the infrageneric relationships can be clarified.

Mannosylxylarinolide, a new 3,4-seco-ergostane-type steroidal saponin featuring a ß-d-mannose from the endophytic fungus Xylaria sp.

Mannosylxylarinolide (1), a new 3,4-seco-ergostane-type steroidal saponin featuring a ß-d-mannose moiety, was isolated from the culture of the endophytic fungus Xylaria sp. that had been isolated from an ornamental plant of Hoya sp. The gross structure was determined by spectroscopic data, and the absolute configuration of the new 3,4-seco-ergostane-type steroidal saponin (1) was determined by X-ray diffraction analysis.

Antiplasmodial and Cytotoxic Cytochalasins from an Endophytic Fungus, Nemania sp. UM10M, Isolated from a Diseased Torreya taxifolia Leaf.

Bioassay-guided fractionation of an EtOAc extract of the broth of the endophytic fungus Nemania sp. UM10M (Xylariaceae) isolated from a diseased Torreya taxifolia leaf afforded three known cytochalasins, 19,20-epoxycytochalasins C (1) and D (2), and 18-deoxy-19,20-epoxy-cytochalasin C (3). All three compounds showed potent in vitro antiplasmodial activity and phytotoxicity with no cytotoxicity to Vero cells. These compounds exhibited moderate to weak cytotoxicity to some of the cell lines of a panel of solid tumor (SK-MEL, KB, BT-549, and SK-OV-3) and kidney epithelial cells (LLC-PK11). Evaluation of in vivo antimalarial activity of 19,20-epoxycytochalasin C (1) in a mouse model at 100 mg/kg dose showed that this compound had weak suppressive antiplasmodial activity and was toxic to animals.

Molecular phylogeny of Ascotricha, including two new marine algae-associated species.

Phylogenetic analyses based on a broad taxonomic sampling of Ascotricha were conducted using the sequences of nuc rDNA region encompassing the internal transcribed spacers 1 and 2, along with the 5.8S rDNA (ITS), partial nuc 18S rDNA (18S) and partial ß-tubulin gene (TUB2). Hypoxyloid Xylariaceae and xylarioid Xylariaceae were inferred as two distinct lineages in the Xylariaceae in the combined ITS-TUB2 phylogeny. Within xylarioid Xylariaceae species of Ascotricha form a monophyletic group. Two new marine algae-associated fungi, Ascotricha longipila and A. parvispora, are described on the basis of morphological and molecular characters and the combination, A. sinuosa, is proposed. A synopsis of the morphological characters and a dichotomous key to Ascotricha species are provided.

New α-pyrone and phthalide from the Xylariaceae fungus.

A new α-pyrone xylaripyrone A (1) and a new phthalide xylariphthalide A (2) were isolated from the Xylariaceae fungus (no. 63-19-7-3), along with four related known phthalides (3-6): 4-[(acetyloxy)methyl]-7-methoxy-6-methyl-1(3H)-isobenzofuranone (3), convolvulol (4), 7-methoxy-4,6-dimethyl-3H-isobenzofuran-1-one (5), and convolvulanic acid B (6). Their structures were determined on the basis of IR, MS, and NMR spectroscopic analyses.

Phylogenetic and taxonomic revision of Lopadostoma.

The genus Lopadostoma (Xylariaceae, Xylariales) is revised. Most species formerly assigned to Lopadostoma do not belong to the genus. Twelve species are herein recognised, of which two are only known from morphology. Ten species, of which six (L. americanum, L. fagi, L. insulare, L. lechatii, L. meridionale and L. quercicola) are newly described, are characterised by both morphology and DNA phylogeny using LSU, ITS and rpb2 sequences. Morphologically, ecologically and phylogenetically Lopadostoma is a well-defined genus comprising exclusively species with pustular pseudostroma development in bark of angiospermous trees. Phaeosperma ailanthi, Phaeosperma dryophilum and Sphaeria linosperma are combined in Lopadostoma. Lopadostoma gastrinum is neotypified and L. turgidum is lecto- and epitypified. Species with asci and ascospores similar to those of Lopadostoma but having perithecia immersed in wood, particularly those of Lopadostoma subg. Anthostomopsis have been determined to be unrelated to the genus. DNA data confirm that Anthostoma is unrelated to Lopadostoma. Its type and currently only confirmed species Anthostoma decipiens belongs to Diatrypaceae. DNA data also show that L. pouzarii and Barrmaelia macrospora are unrelated to Lopadostoma. A commentary is provided for names in Lopadostoma and those names in Anthostoma that may be putative species of Lopadostoma based on their protologues. Anthostoma insidiosum is an older name for Anthostomella (Diatrype) adusta.

Complete mitochondrial genome sequence of the white root rot pathogen Dematophora necatrix (Xylariaceae: Xylariales).

The mitochondrial genome of Dematophora necatrix is 121,350 base pairs in length with a G + C content of 30.19%. Phylogenetic analysis showed that D. necatrix grouped with other members of the Xylariaceae, with which its mitogenome also shares a broadly similar architecture and gene content. The D. necatrix mitogenome contains 14 protein-coding and 26 tRNA-encoding genes, as well as one copy each of the rnl, rns, rps3 and nat1 genes. However, as much as 80% of this genome is intronic or non-coding. This is likely due to expansions and rearrangements caused by the large number of group I introns and the homing endonucleases and reverse-transcriptases they encode. Our study thus provides a valuable foundation from which to explore the mitochondrion's role in the biology of D. necatrix, and also serves as a resource for investigating the pathogen's population biology and general ecology.

Xylatolides A and B, new 10-membered macrolides from the endophytic fungus Xylaria sp.

Chemical investigation of the fungal endophyte Xylaria sp. isolated from leaves of Moringa oleifera, collected in Cameroon, resulted in the previously undescribed 10-membered macrolide, and two known natural products. The structures of the xylatolides A and B were unambiguously identified by their mass spectra and by extensive 1D and 2D NMR spectroscopic analysis, featuring a 10-membered lactone core structure with oxygenated substituents and an unsubstituted 10-alkyl chain presenting seven carbon atoms. Compounds were screened for their cytotoxic potential against the human HepG2 hepatocellular carcinoma cells and HCT-116 cells (human colon carcinoma cell line). Moreover, the isolated compounds were also assayed against a small panel of sensitive strains including the bacterial species Escherichia coli, Staphylococcus aureus, and Mycobacterium tuberculosis as well as against the fungal species Candida albicans. However, no significant activities were found.

Morphology and multigene phylogeny reveal four new Xylaria (Xylariales, Xylariaceae) species from karst region in China.

This study presents the identification of four novel Xylaria species, discovered in the karst region of China. The discovery was facilitated by a rigorous analysis that encompassed both morpho-anatomical features and multi-locus phylogenetics utilizing sequences from the ITS, rpb2, and TUB2 loci. The newly identified species are designated as Xylariajichuanii sp. nov., X.nanningensis sp. nov., X.orientalis sp. nov., and X.taiyangheensis sp. nov. The distinction of these species from their known counterparts was verified through comparison of morphological features and phylogenetic analysis. The study further provides detailed morphological descriptions, illustrative representations, and a phylogenetic tree, all of which contribute to the taxonomic positioning of these novel species.

Two new quinoline alkaloid with neuroprotective activities from Xylaria longipes.

Two new quinoline alkaloids with an α, ß-unsaturated amide side chain, xylarinines A and B (1 and 2), were isolated from the ethyl acetate extracts of Xylaria longipes solid fermentation. The structures of these were primarily determined though NMR and HRESIMS data analysis. The absolute configuration of compound 1 was assigned using experimental and calculated ECD data. The neuroprotective effects of compounds 1 and 2 against glutamate-induced damage in PC12 cells were evaluated in vitro bioassay. The results demonstrated that both compounds significantly improved cell viability, inhibited apoptosis, decreased malondialdehyde (MDA) levels, increased superoxide dismutase (SOD) and glutathione (GSH) levels, and reduced intracellular reactive oxygen species (ROS) accumulation. These findings suggested that these mechanisms contribute to the neuroprotective effects of the compounds.

Multi-gene phylogenetic and taxonomic contributions to Xylaria (Ascomycota) associated with fallen fruits from China.

Morphological and phylogenetic analyses on samples of Xylaria species associated with fallen fruits from China were carried out, and two new species were described, namely X.aleuriticola and X.microcarpa. Xylariaaleuriticola is found on fallen fruits of Aleuritesmoluccana, and characterized by stromata dichotomously branched several times with long acute sterile apices, fertile parts roughened with perithecia and tomentose, and ellipsoid to fusiform ascospores. Xylariamicrocarpa differs in its very small stromata with dark brown tomentum, light brown ascospores with an inconspicuous straight germ slit, and grows on leguminous pods. The differences between the new species and morphologically similar species are discussed. Phylogenetic analyses on ITS-RPB2-TUB sequences confirmed that the two species are clearly separated from other species of the genus Xylaria. Xylarialiquidambaris is reported as a new record from China. A key to the Xylaria species associated with fallen fruits and seeds reported from China is provided to facilitate future studies of the genus.

Xylaria furcata reconsidered and nine resembling species.

BACKGROUND: Xylaria collections from termite nests with dichotomously branched stromata have been identified as X. furcata. However, Léveillé's original material is no longer available, and the modern interpretation of X. furcata is based on a 1908 collection made by von Höhnel from termite nests at Buitenzorg Botanical Garden in Java. A packet of this von Höhnel material at FH was designated as the neotype by Rogers et al. in 2005. RESULTS: We reexamined the neotype from FH and its duplicates from various herbaria and found that three different species were mixed in these specimens. Despite that all of them have dichotomously branched stromata and tiny ascospores, only one fits the 2005 neotypification of X. furcata, where exposed perithecial mounds on the stromatal surface were unambiguously indicated. This portion of material is redesignated as the neotype, while the other two species with immersed perithecia are described as new: X. hoehnelii and X. robustifurcata. The ITS sequence obtained from the neotype helped us designate a specimen with cultures obtained from it as the epitype. From specimens identifiable as X. furcata, we describe four new species: X. brevifurcata, X. furcatula, X. insignifurcata, and X. tenellifurcata. Additionally, we recognize X. furcata var. hirsuta at the species level as X. hirsuta and consider X. scoparia a distinct species rather than a synonym of X. furcata. Molecular phylogenetic analyses based on three protein-coding loci showed that X. furcata and resembling species were grouped into two clusters: the X. furcata cluster with half-exposed to fully exposed perithecial mounds and the X. hoehnelii cluster with largely immersed perithecial mounds. CONCLUSION: Ten species are recognized for X. furcata and resembling species, all of which could have been identified as X. furcata in the past. Its diversity has been overlooked primarily due to the small and similar stromata. Several additional species have been confirmed to be related to X. furcata by DNA sequences but are yet to be described due to the lack of mature stromata. While the species diversity of macrotermitine termites is equally high in Africa as in Asia, all of the species are primarily found in Asia, with X. hirsuta as the only exception. This suggests that there may be many more undiscovered species for this fungal group.

Seco-pimarane diterpenoids and androstane steroids from an endophytic Nodulisporium fungus derived from Cyclosorus parasiticus.

Five previously undescribed specialized metabolites, including three 9,11-seco-pimarane diterpenoids, nodulisporenones A-C, and two androstane steroids, nodulisporisterones A and B, together with previously described ergosterol derivatives, dankasterone A and demethylincisterol A3, were isolated from solid cultures of the endophytic fungus Nodulisporium sp. SC-J597. Their structures including absolute configurations were elucidated by extensive spectroscopic analysis and theoretical calculations of electronic circular dichroism spectra. Among them, nodulisporenones A and B are the first examples of seco-pimarane diterpenoids that is cyclized to form an unprecedented diterpenoid lactone scaffold and nodulisporisterones A and B represent the first normal C19 androstane steroids of fungal origin. Nodulisporisterone B exhibited potent inhibitory effect on the production of NO in LPS-stimulated RAW264.7 macrophages (IC50 = 2.95 µM). This compound, together with the two known ergosterol derivatives, also displayed cytotoxicity against A549, HeLa, HepG2 and MCF-7 cancer cell lines with IC50 values of 5.2-16.9 µM.

Neuroprotective methylsuccinic acid and enoic acid derivatives from the fungus Xylaria longipes.

Three undescribed methylsuccinic acid derivatives, xylaril acids A-C, and two undescribed enoic acid derivatives, xylaril acids D-E, were isolated from the fungus Xylaria longipes. The structures of the undescribed compounds were deduced by spectroscopic means, including HRESIMS and 1D/2D NMR spectroscopy, as well as ECD calculations. The absolute configuration of xylaril acids A was further determined by single-crystal X-ray diffraction experiments. All the isolated compounds displayed neuroprotective activities against oxygen-glucose deprivation/reperfusion injury in PC12 cells by enhancing cell viability and inhibiting cell apoptosis.

Lopadostoma, Oligostoma, and some Rosellinia specimens from the herbarium of the Swiss Federal Institute of Technology (ZT): the value of early fieldwork and the importance of keeping fungal collections.

BACKGROUND: Morphology, hosts, and collecting sites of fungi assessed from herbarium material of special interest deserve to be brought to the attention of mycologists. RESULTS: Specimens of Lopadostoma and Oligostoma deposited at ZT are briefly described and listed to expand the knowledge about their distribution. Three yet unmentioned Rosellinia collections are reported. One could be identified as R. mastoidiformis, a second as R. neblina; both are known only from the type collections. The third one seems to be a yet undescribed taxon and is formally described as R. schueppii. CONCLUSIONS: These observations emphasize the importance of keeping fungal collections and highlight the importance of field work and contributions by early mycologists.

Cytochalasans produced by Xylaria karyophthora and their biological activities.

The recent description of the putative fungal pathogen of greenheart trees, Xylaria karyophthora (Xylariaceae, Ascomycota), prompted a study of its secondary metabolism to access its ability to produce cytochalasans in culture. Solid-state fermentation of the ex-type strain on rice medium resulted in the isolation of a series of 19,20-epoxidated cytochalasins by means of preparative high-performance liquid chromatography (HPLC). Nine out of 10 compounds could be assigned to previously described structures, with one compound being new to science after structural assignment via nuclear magnetic resonance (NMR) assisted by high-resolution mass spectrometry (HRMS). We propose the trivial name "karyochalasin" for the unprecedented metabolite. The compounds were used in our ongoing screening campaign to study the structure-activity relationship of this family of compounds. This was done by examining their cytotoxicity against eukaryotic cells and impact on the organization of networks built by their main target, actin-a protein indispensable for processes mediating cellular shape changes and movement. Moreover, the cytochalasins' ability to inhibit the biofilm formation of Candida albicans and Staphylococcus aureus was examined.

Exploring the Xylariaceae and its relatives.

The Xylariaceae and its relatives rank as one of the best-known members of the Ascomycota. They are now well recognized for their diversity, global distribution, ecological activities and their outstanding novel metabolites with wide ranging bioactivity.

Xylaria species associated with fallen leaves and petioles.

BACKGROUND: Xylaria species growing on fallen leaves and petioles have not been treated systematically. One source of confusion in this group of Xylaria species has stemmed from X. filiformis, which is an ancient name published in 1805 as Sphaeria filiformis and has commonly labeled on specimen packets that contain leaf- and petiole-inhabiting Xylaria species. Here we clarified the identity of X. filiformis and distinguish it from the species that are easily confused with it, notably X. simplicissima, to which most specimens labeled as X. filiformis are referred. Our research also led us to encounter many other leaf- and petiole-inhabiting Xylaria species, prompting a comprehensive study of this group of fungi. RESULTS: Forty-five foliicolous and caulicolous species of Xylaria were studied, including nine newly described species-X. allima, X. appendiculatoides, X. hispidipes, X. minuscula, X. neblinensis, X. spiculaticlavata, X. vermiformis, X. vittatipiliformis, and X. vittiformis; three unnamed species-X. sp. AR1741, X. sp. GS7461A, and X. sp. GS7461B; X. simplicissima, a name newly combined with Xylaria from Rhizomorpha simplicissima; and X. noduliformis and X. imminuta, which are two new replacement names, respectively, for X. maitlandii var. nuda and X. hypsipoda var. microspora. The 45 taxa can be classified into three groups by stromatal shape and conspicuousness of perithecial mounds on the stromatal surface: (i) the X. filiformis group contains 10 species, (ii) the X. phyllocharis group contains 19 species, and (iii) the X. heloidea group contains 16 species. One of the newly described or unnamed species belongs to the X. filiformis group-X. vermiformis; nine of them belong to the X. phyllocharis group-X. allima, X. appendiculatoides, Xylaria minuscula, X. neblinensis, X. sp. AR1741, X. sp. GS7461B, X. spiculaticlavata, X. vittatipiliformis, and X. vittiformis; and three of them belong to the X. heloidea group-X. hispidipes, X. imminuta, and X. sp. GS7461A. CONCLUSION: The 45 species of Xylaria associated with fallen leaves and petioles can be identified by using the dichotomous identification key that we provided herein. It is important to note that most of the studied species are represented by only one or several specimens and many have not been recollected and cultured.

New paraconic acids from the endophytic fungus Xylariaceae sp. J4.

Three new paraconic acids, xylariacinics A-C (1-3), were isolated from the endophyte Xylariaceae sp. J4 harbored in the medicinal plant Blumea balsamifera. Their structures were elucidated on the basis of extensive spectroscopic data including HRMS, and NMR. The antibacterial efficacies of compounds 1-3 were evaluated against a panel of bacteria such as Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. Their antifungal activities were also tested against Colletotrichum gloeosporioides. Unfortunately, all of them were inactive.