200 years of taxonomic confusion: Sporendonema and allies.

The genus Sporendonema (Gymnoascaceae, Onygenales) was introduced in 1827 with the type species S. casei for a red mould on cheese. Cheese is a consistent niche for this species. Sphaerosporium equinum is another species classified in Gymnoascaceae and has also been reported from cheese. Recently, other habitats have been reported for both Sporendonema casei and Sphaerosporium equinum. The present study aimed to investigate the taxonomy of Sporendonema and Sphaerosporium, as well as a close neighbour, Arachniotus. Two strains of Hormiscium aurantiacum, another related cheese-associated species were also included in the analyses. Strains were evaluated in terms of macro- and micromorphology, physiology including salt tolerance, growth rate at different temperatures, casein degradation, cellulase activity, lipolytic activity, and multi-locus phylogeny with sequences of the nuclear ribosomal internal transcribed spacer region, the D1-D2 region of the large subunit and partial ß-tubulin locus sequences. The results showed that the analysed species were congeneric, and the generic names Arachniotus and Sphaerosporium should be reduced to the synonymy of Sporendonema. Therefore, four new combinations as well as one lectotype and one epitype were designated in Sporendonema. Two strains attributed to Sphaerosporium equinum from substrates other than cheese were found to be phylogenetically and morphologically deviant and were introduced as a new species named Sporendonema isthmoides.

Calamene-Type Sesqui-, Mero-, and Bis-sesquiterpenoids from Cultures of Heimiomyces sp., a Basidiomycete Collected in Africa.

New meroterpenoids bis-heimiomycins A-D (1-4) and heimiomycins D and E (5 and 6) were isolated from solid rice cultures of Heimiomyces sp., while new calamene-type sesquiterpenoids heimiocalamene A (7) and B (8) were isolated from shake cultures, respectively. Structures of the metabolites were elucidated by 1D and 2D NMR in addition to HRESIMS data. While relative configurations were assigned by ROESY data, absolute configurations were derived from the structurally related, previously described calamenes, which we herein name heimiocalamenes C-E (9-11). A plausible biosynthetic pathway was proposed for 1-6, with a radical reaction connecting their central para-benzoquinone building block to calamene-sesquiterpenoids. Based on the assumption of a common biosynthesis, we reviewed the structure of the known nitrogen-containing derivative 11, calling the validity of the originally proposed structure into question. Subsequently, the structure of 11 was revised by analysis of HMBC and ROESY NMR data. Only heimiomycin D (5) displayed cytotoxic effects against cell line KB3.1.

Neurite Outgrowth-Inducing Drimane-Type Sesquiterpenoids Isolated from Cultures of the Polypore Abundisporus violaceus MUCL 56355.

Abundisporin A (1), together with seven previously undescribed drimane sesquiterpenes named abundisporins B-H (2-8), were isolated from a polypore, Abundisporus violaceus MUCL 56355 (Polyporaceae), collected in Kenya. Chemical structures of the isolated compounds were elucidated based on exhaustive 1D and 2D NMR spectroscopic measurements and supported by HRESIMS data. The absolute configurations of the isolated compounds were determined by using Mosher's method for 1-4 and TDDFT-ECD calculations for 4 and 5-8. None of the isolated compounds exhibited significant activities in either antimicrobial or cytotoxicity assays. Notably, all of the tested compounds demonstrated neurotrophic effects, with 1 and 6 significantly increasing outgrowth of neurites when treated with 5 ng/mL NGF.

Heimionones A-E, New Sesquiterpenoids Produced by Heimiomyces sp., a Basidiomycete Collected in Africa.

With heimionones A-E (1-5), five new terpenoids were isolated from submerged cultures of Heimiomyces sp. in addition to the previously described compounds hispidin, hypholomin B, and heimiomycins A and B. Planar structures of the metabolites were elucidated by 1D and 2D NMR in addition to HRESIMS data. While ROESY data assigned relative configurations, absolute configurations were determined by the synthesis of MTPA esters of 1, 3, and 5. The [6.3.0] undecane core structure of compounds 3-5 is of the asteriscane-type, however, the scaffold of 1 and 2 with their bicyclo [5.3.0] decane core and germinal methyl substitution is, to our knowledge, unprecedented. Together with several new compounds that were previously isolated from solid cultures of this strain, Heimiomyces sp. showed an exceptionally high chemical diversity of its secondary metabolite profile.

Two new lanostanoid glycosides isolated from a Kenyan polypore Fomitopsis carnea.

Chemical exploration of solid-state cultures of the polypore Fomitopsis carnea afforded two new C31 lanostane-type triterpenoid glycosides, forpiniosides B (1) and C (2) together with two known derivatives, namely 3-epipachymic acid (3) and (3α,25S)-3-O-malonyl-23-oxolanost-8,24(31)-dien-26-oic acid (4). The structures of the isolated compounds were established based on HRESIMS and extensive 1D and 2D NMR experiments. All the isolated compounds were assessed for their antimicrobial and cytotoxic activities. Among the tested compounds, forpinioside B (1) exhibited significant antimicrobial activity against Staphylococcus aureus and Bacillus subtilis at MIC values comparable to gentamycin and oxytetracycline (positive controls), respectively.

Terpenoids and Meroterpenoids from Cultures of Two Grass-Associated Species of Amylosporus (Basidiomycota).

An investigation of the chemical components of the fermentation extract of two cultures of Amylosporus cf. graminicola and Amylosporus cf. campbelii from Cuba and Zimbabwe, respectively, led to the isolation of seven previously undescribed secondary metabolites for which we proposed the trivial names amylosporanes A-G (1-7) along with the known compounds orsellinic acid (11), colletorin D acid (12), colletorin B (13), colletochlorin B (14), and the ß-lactam cyclo-(S-Pro-R-Leu) (15). Three additional compounds (8-10) previously unknown from a fungal source were also characterized for the first time, and two of them were assigned the trivial names amylosporanes H-I (8-9) while the other was identified as cannabigerorcinic acid (10). The structures of the isolated compounds were determined based on their high-resolution electrospray ionization mass spectrometry (HR-ESIMS) spectra and an extensive analysis of their 1D and 2D NMR spectroscopic data. Based on literature searches, we hypothesized that a majority of the isolated metabolites have orsellinic acid (11) as a biosynthetic precursor following a combined route of mevalonate-associated and orsellinic acid-associated pathways. Colletochlorin B (14), the only compound possessing chlorine in its structure, exhibited significant activity against Bacillus subtilis (minimum inhibitory concentration, 2 µg/mL), stronger than that of oxytetracycline, and significant cytotoxicity against A431 cells with an IC50 value of 4.6 µM.

Neurotrophic and Immunomodulatory Lanostane Triterpenoids from Wood-Inhabiting Basidiomycota.

Neurotrophins such as nerve growth factor (ngf) and brain-derived neurotrophic factor (bdnf) play important roles in the central nervous system. They are potential therapeutic drugs for the treatment of neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. In this study, we investigated the neurotrophic properties of triterpenes isolated from fruiting bodies of Laetiporus sulphureus and a mycelial culture of Antrodia sp. MUCL 56049. The structures of the isolated compounds were elucidated based on nuclear magnetic resonance (NMR) spectroscopy in combination with high-resolution electrospray mass spectrometry (HR-ESIMS). The secondary metabolites were tested for neurotrophin (ngf and bdnf) expression levels on human astrocytoma 1321N1 cells. Neurite outgrowth activity using rat pheochromocytoma (PC-12) cells was also determined. Twelve triterpenoids were isolated, of which several potently stimulated the expression of neurotrophic factors, namely, ngf (sulphurenic acid, 15α-dehydroxytrametenolic acid, fomefficinic acid D, and 16α-hydroxyeburicoic acid) and bdnf (sulphurenic acid and 15α-dehydroxytrametenolic acid), respectively. The triterpenes also potentiated ngf-induced neurite outgrowth in PC-12 cells. This is, to the best of our knowledge, the first report on the compound class of lanostanes in direct relation to bdnf and ngf enhancement. These compounds are widespread in medicinal mushrooms; hence, they appear promising as a starting point for the development of drugs and mycopharmaceuticals to combat neurodegenerative diseases. Interestingly, they do not show any pronounced cytotoxicity and may, therefore, be better suited for therapy than many other neurotrophic compounds that were previously reported.

Drimane-Type Sesquiterpenoids Derived from the Tropical Basidiomycetes Perenniporia centrali-africana and Cerrena sp. nov.

Five new drimane-type sesquiterpenoids were isolated from cultures of the tropical basidiomycetes, Perenniporia centrali-africana (originating from Kenya) and Cerrena sp. nov. (originating from Thailand). A new pereniporin A derivative (1), a new drimane-type sesquiterpene lactam (2), and the new 6,7-Dehydro-isodrimenediol (3) were isolated from P. centrali-africana. In parallel, the two new drimane-type sesquiterpene lactams 5 and 6 were isolated together with known isodrimenediol (4) from Cerrena sp. This is the first report of drimane-type sesquiterpene lactams from basidiomycetes. The structures were elucidated based on 1D and 2D nuclear magnetic resonance (NMR) spectroscopic data, in combination with high-resolution electrospray mass spectrometric (HR-ESIMS) data. The compounds were devoid of significant antimicrobial and cytotoxic activities.

Heimiomycins A-C and Calamenens from the African Basidiomycete Heimiomyces sp.

Three previously undescribed compounds named heimiomycin A-C (1-3), featuring a unique scaffold with calamenene connected to a hydroxystyryl-pyranone moiety, along with the new calamenene derivatives 4 and 5 and phenanthridine derivative (6) were obtained from a culture of a Heimiomyces sp. This is the first report of the occurrence of calamenene-type terpenoids in fungi. Compound 3 exhibited antimicrobial activity against Gram-positive bacteria and Mucor hiemalis. Compounds 1 and 3 displayed moderate cytotoxicity against KB 3.1 and L929 cell lines, respectively.

Sesquiterpenes from an Eastern African Medicinal Mushroom Belonging to the Genus Sanghuangporus.

During the course of searching for new anti-infective and other biologically active secondary metabolites from Kenyan basidiomycetes, 13 previously undescribed metabolites, (6 R,7 S,10 R)-7,10-epoxy-7,11-dimethyldodec-1-ene-6,11-diol (1) and 12 sesquiterpenes named elgonenes A-L (2-13), and the known compound P-coumaric acid (14) were isolated from a basidiomycete collected in Mount Elgon Natural Reserve. The producing organism represents a new species of the genus Sanghuangporus, which is one of the segregates of the important traditional Asian medicinal mushrooms that were formerly known as the " Inonotus linteus" complex. The structure elucidation of compounds 1-13, based on 2D NMR spectroscopy, high-resolution mass spectrometry, and other spectral methods, and their antibacterial, antifungal, and cytotoxic activities are reported.

Skeletocutins M-Q: biologically active compounds from the fruiting bodies of the basidiomycete Skeletocutis sp. collected in Africa.

During the course of screening for new metabolites from basidiomycetes, we isolated and characterized five previously undescribed secondary metabolites, skeletocutins M-Q (1-5), along with the known metabolite tyromycin A (6) from the fruiting bodies of the polypore Skeletocutis sp. The new compounds did not exhibit any antimicrobial, cytotoxic, or nematicidal activities. However, compound 3 moderately inhibited the biofilm formation of Staphylococcus aureus (S. aureus), while compounds 3 and 4 performed moderately in the ʟ-leucine-7-amido-4-methylcoumarin (ʟ-Leu-AMC) inhibition assay. These compounds represent the first secondary metabolites reported to occur in the fruiting bodies by Skeletocutis. Interestingly, tyromycin A (6) was found to be the only common metabolite in fruiting bodies and mycelial cultures of the fungus, and none of the recently reported skeletocutins from the culture of the same strain were detected in the basidiomes.

Microporenic Acids A-G, Biofilm Inhibitors, and Antimicrobial Agents from the Basidiomycete Microporus Species.

The need for effective compounds to combat antimicrobial resistance and biofilms which play important roles in human infections continues to pose a major health challenge. Seven previously undescribed acyclic diterpenes linked to isocitric acid by an ether linkage, microporenic acids A-G (1-7), were isolated from the cultures of a hitherto undescribed species of the genus Microporus (Polyporales, Basidiomycota) originating from Kenya's Kakamega forest. Microporenic acids D and E (4 and 5) showed antimicrobial activity against a panel of Gram positive bacteria and a yeast, Candida tenuis. Moreover, microporenic acids A and B (1 and 2) demonstrated dose-dependent inhibition of biofilm formation by Staphylococcus aureus. Compound 1 further showed significant activity against Candida albicans and Staphylococcus aureus preformed biofilms.

Aethiopinolones A-E, New Pregnenolone Type Steroids from the East African Basidiomycete Fomitiporia aethiopica.

A mycelial culture of the Kenyan basidiomycete Fomitiporia aethiopica was fermented on rice and the cultures were extracted with methanol. Subsequent HPLC profiling and preparative chromatography of its crude extract led to the isolation of five previously undescribed pregnenolone type triterpenes 1-5, for which we propose the trivial name aethiopinolones A-E. The chemical structures of the aethiopinolones were determined by extensive 1D- and 2D-NMR, and HRMS data analysis. The compounds exhibited moderate cytotoxic effects against various human cancer cell lines, but they were found devoid of significant nematicidal and antimicrobial activities.

Are there keystone mycorrhizal fungi associated to tropical epiphytic orchids?

In epiphytic orchids, distinctive groups of fungi are involved in the symbiotic association. However, little is known about the factors that determine the mycorrhizal community structure. Here, we analyzed the orchid mycorrhizal fungi communities associated with three sympatric Cymbidieae epiphytic tropical orchids (Cyrtochilum flexuosum, Cyrtochilum myanthum, and Maxillaria calantha) at two sites located within the mountain rainforest of southern Ecuador. To characterize these communities at each orchid population, the ITS2 region was analyzed by Illumina MiSeq technology. Fifty-five mycorrhizal fungi operational taxonomic units (OTUs) putatively attributed to members of Serendipitaceae, Ceratobasidiaceae and Tulasnellaceae were identified. Significant differences in mycorrhizal communities were detected between the three sympatric orchid species as well as among sites/populations. Interestingly, some mycorrhizal OTUs overlapped among orchid populations. Our results suggested that populations of studied epiphytic orchids have site-adjusted mycorrhizal communities structured around keystone fungal species. Interaction with multiple mycorrhizal fungi could favor orchid site occurrence and co-existence among several orchid species.

Multilocus, DNA-based phylogenetic analyses reveal three new species lineages in the Phellinus gabonensis-P. caribaeo-quercicola species complex, including P. amazonicus sp. nov.

Species complexes in the poroid Hymenochaetaceae are well documented in the temperate areas. Potential species complexes are less known in tropical areas, however. In the last ten years, four phylogenetically and morphologically closely related species of Phellinus (Hymenochaetaceae) were described from various tropical/subtropical areas viz. P. caribaeo-quercicola, P. gabonensis, P. ellipsoideus, and P. castanopsidis They are characterized by cushion-shaped basidiomata, ventricose, commonly hamate hymenial setae, and broadly ellipsoid, thick-walled, pale yellowish basidiospores. Pursuing the studies of this complex, a phylogenetic approach based on DNA sequence data from the nuc rDNA regions ITS1-5.8S-ITS2 (ITS) and partial 28S (including the domains D1, D2, D3) and on part of the translation elongation factor 1-α (tef1, region between exons 4 and 8) revealed three new lineages or phylogenetic species. Two of these phylogenetic species are composed of exclusively on Neotropical specimens. One of them, described below as Phellinus amazonicus sp. nov., is represented by multiple collections originating from Neotropical, lowland, dense, moist forest at the western edge of the Amazon Basin in Ecuador, the Guiana Shield in French Guiana and (more likely) Trinidad. The second Neotropical phylogenetic species is represented in our phylogenetic analyses by a single collection from northeastern Argentina. It is also potentially known from two herbarium specimens originating from southern Brazil, for which no sequence data is available. It is left for now as Phellinus sp. 1, waiting to gather more specimens and DNA sequences data. The third new phylogenetic species is known by a single collection (pure culture) of uncertain origin. It is thought to represent Phellinus setulosus, a Southeast Asian taxa. From an evolutionary perspective, tree species occurring in the Neotropics (P. amazonicus, P. caribaeo-quercicola, and Phellinus sp. 1) have a closely related genetic background and form a well supported Neotropical lineage.

Hymenochaetaceae from the Guineo-Congolian rainforest: three new species of Phylloporia based on morphological, DNA sequences and ecological data.

Four species are added to Phylloporia. Three species, originating from the western edge of the Guineo-Congolian rainforest in Gabon (central Africa), are described as new. Phylloporia afrospathulata sp. nov. forms seasonal, stipitate, solitary basidiomata emerging from soil, more likely connected to buried roots, and has broadly ellipsoid basidiospores. Phylloporia inonotoides sp. nov. forms seasonal sessile, soft basidiomata, solitary at the base of small-stemmed trees including Crotonogyne manniana (Euphorbiaceae) and Garcinia cf. smeathmannii (Clusiaceae). It has a homogeneous context, large pores (2-3 mm), and oblong-ellipsoid to suballantoid basidiospores. Phylloporia fulva sp. nov. forms sessile, conchate, mostly pendant, gregarious basidiomata emerging from the trunk of an unidentified small-stemmed tree and has small, subglobose basidiospores. This species is compared to Polyporus pullus and Phylloporia pulla comb. nov. and proposed based on the study of the type specimen. Phylogenetic inferences using partial nuc 28S DNA sequence data (region including the D1/D2/D3 domains) and the most exhaustive dataset available to date resolved these new morphospecies as three distinct terminal lineages. No sequence data of P. pulla currently is available. The 28S-based phylogenic inferences poorly resolved the interspecific relationships within the Phylloporia clade.

Pithomyces species (Montagnulaceae) from clinical specimens: identification and antifungal susceptibility profiles.

The fungal genus Pithomyces comprises numerous dematiaceous saprobic species commonly found on dead leaves and stems of a great variety of plants. Occasionally, they have been recovered from clinical specimens. We morphologically and molecularly (rDNA sequences) investigated a set of 42 isolates tentatively identified as Pithomyces recovered from clinical specimens in the United States. The predominant species were P. chartarum and P. sacchari (33.3% each), followed by Pithomyces sp. I (28.6%) and P. maydicus (4.8%). Most of the isolates were obtained from samples of superficial tissue (50%), the respiratory tract (21.4%), and the nasal region (19%). In general, these fungi were highly susceptible in vitro to the eight antifungal agents tested.

A polyphasic taxonomy of Daldinia (Xylariaceae).

For a monograph based on a polythetic concept, several thousands of herbarium specimens, and several hundreds of freshly collected and cultured specimens of Daldinia and allied Xylariaceae, originating from around the world, were studied for morphological traits, including by SEM, and chemically by HPLC profiles using UV-visible and mass spectrometric detection. Emphasis was given to tropical material, and importantly, ancient specimens, including as many types as possible, were tracked and studied to review earlier taxonomic concepts. An epitype of D. eschscholtzii was selected as representative of the morphochemotype that is most widely distributed in the tropics. Six new species of Daldinia from the tropics and the southern Hemisphere are described. Daldinia asphalatum is resurrected, and D. cudonia is regarded as its synonym. In addition, the following binomials are epi-, iso-, neo- and/or lectotypified: Daldinia asphalatum, D. caldariorum, D. clavata, D. cuprea, D. durissima, D. eschscholtzii, D. grandis, D. loculata, and D. vernicosa. Annellosporium and Versiomyces are regarded as synonyms of Daldinia. Many new synonymies in Daldinia are proposed, and some previously published names are rejected. In total, 47 taxa in Daldinia are recognised and a key is provided. Their biogeography, chorology, and ecology, as well as the importance of their secondary metabolites, are also discussed. The previous definition of the genus is emended. The species concept is based mainly on morphological and other phenotype-derived characters because, despite diligent search, no molecular data or cultures of several of the accepted species could be obtained. Daldinia is segregated into five major groups, based on phenotypic characteristics. Some unnamed but aberrant specimens were not found in good condition and are therefore not formally described as new species. However, they are illustrated in detail in a hope that this will facilitate the discovery of fresh material in future. A preliminary molecular phylogeny based on 5.8S/ITS nrDNA including numerous representatives of all hitherto described taxa for which cultures are extant, was found basically in agreement with the above mentioned segregation of the genus, based on morphological and chemotaxonomic evidence. In the rDNA based phylogenetic tree, Daldinia appears clearly distinct from members of the genera Annulohypoxylon and Hypoxylon; nevertheless, representatives of small genera of predominantly tropical origin (Entonaema, Phylacia, Ruwenzoria, Rhopalostroma, Thamnomyces) appear to have evolved from daldinioid ancestors and are nested inside the Daldinia clade. Interestingly, these findings correlate with chemotaxonomic characters to a great extent, especially regarding the distribution of marker metabolites in their mycelial cultures. Hence, the current study revealed for the first time that fungal secondary metabolite profiles can have taxonomic value beyond the species rank and even coincide with phylogenetic data. TAXONOMIC NOVELTIES: Daldinia andina sp. nov., D. australis sp. nov., D. hausknechtii sp. nov., D. rehmii sp. nov., D. starbaeckii sp. nov., D. theissenii sp. nov., D. cahuchosa comb. nov., D. nemorosa comb. nov.

Acremonium with catenate elongate conidia: phylogeny of Acremonium fusidioides and related species.

Acremonium is one of the largest and most complex genera of hyphomycetes. Its taxonomy is not yet resolved and the phylogenetic value of the most distinctive morphological features is unknown. The species of this genus produce conidia in chains or form slimy heads or both. We have studied a set of clinical and environmental Acremonium strains morphologically characterized by producing mostly catenate, elongate, more or less fusiform conidia. Based on phenotypic data and in the analysis of the sequences of the ITS region, the D1/D2 domains of the 28S rRNA gene and a fragment of the ß-tubulin gene, three new species morphologically similar to Acremonium fusidioides and belonging to the family Bionectriaceae (Hypocreales) are described and illustrated; they are Acremonium pilosum, Acremonium parvum and Acremonium citrinum. The first species produces two kinds of conidia: clavate with smooth walls and globose with abundant filiform projections. Acremonium parvum is characterized by slow growth and pyriform or slightly lanceolate conidia with an elongate and truncate base. Acremonium citrinum produces a diffusible yellow pigment and obovoid conidia.

Fomes weberianus, 50 years of taxonomic confusion: lectotypification and taxonomic notes.

Fomes weberianus Bres. & Henn. ex Sacc. is currently the basionym of two very distinct polypores (Basidiomycota), Ganoderma weberianum (Polyporales) and Phylloporia weberiana (Hymenochaetales). This fact has led to almost fifty years of taxonomic confusion. Fomes weberianus was first lectotypified by Steyaert, who accepted the species as G. weberianum. However, studies of Weber's original material in B, duplicate material in S, the protologue, and early interpretations of the name have shown that Steyaert's choice conflicts with the protologue and early interpretations, and that his interpretation as a species of Ganoderma is erroneous. A new lectotype was designated and the species was re-described under the correct interpretation Phylloporia weberiana.