Neohelicomyces species are a group of helicosporous hyphomycetes with the potential to produce secondary metabolites. During our investigation of helicosporous fungi, six collections were isolated from both terrestrial and freshwater habitats in Guizhou Province, China. Based on multigene phylogenetic analysis (ITS, LSU, tef1α and rpb2), coupled with morphological data, three new Neohelicomyces species, viz. N. guizhouensis, N. helicosporus and N. hydei were established. A list of accepted Neohelicomyces species with molecular data was provided. The strain of Neohelicomyces pallidus (UAMH 10535) was synonymised under N. denticulatus based on molecular data.

During our investigation of saprobic fungi in southwestern China, three micro-hyphomycetous fungi were isolated from dead wood in freshwater and terrestrial habitats in Guizhou Province. Phylogenetic analyses of ITS, LSU, and SSU sequences, performed using Maximum Likelihood and Bayesian Inference methods, confirmed that these isolates belong to Kirschsteiniothelia. Based on distinct morphological characteristics and molecular phylogenetic evidence, we describe three new species: Kirschsteiniothelia guizhouensis, K. weiningensis, and K. xishuiensis. Furthermore, the effectiveness of three DNA markers for species-level identification within Kirschsteiniothelia was evaluated using Assemble Species by Automatic Partitioning (ASAP) analysis, which identified the ITS nucleotide sequences as the most reliable marker for species differentiation within the genus.

Helicosporous hyphomycetes is a group of filamentous fungi that shows promising application prospects in metabolizing bioactive natural compounds. During a study of helicosporous fungi in China, six new helicosporous taxa were collected and isolated from decaying wood in Guangxi Zhuang Autonomous Region, China. Morphological comparisons with multi-gene phylogenetic analyses revealed that these six taxa belong to Helicosporium (Tubeufiaceae, Tubeufiales), and they were recognized as three novel species and were named Helicosporium liuzhouense, H. multidentatum, and H. nanningense. Detailed descriptions and illustrations of the newly discovered taxa and comparisons with similar fungi are provided. In addition, a list and a key to accepted Helicosporium species are provided.

During an investigation of helicosporous fungi in China, a total of seven helicosporous hyphomycetes were obtained from decaying wood in the southern region of the country. Based on phylogenetic analyses using a combined LSU, ITS, tef1α, and rpb2 sequence matrix, in conjunction with morphological comparisons, these taxa were classified within Tubeufia (Tubeufiaceae, Tubeufiales) and were recognized as three new species, viz. Tubeufia guttulata, T. hainanensis, and T. muriformis, as well as one new distribution record, viz. T. cocois. Evidence for these new taxa and the new record, descriptions, illustrations, notes, and phylogenetic evidence are provided for the newly collected helicosporous species.

From the rice fermentation product of a new record fungus, Neohelicosporium griseum, two new polyketides, neogrisphenol A (1) and neogrisphenol B (2), one new isochroman-1-one, (S)-6-hydroxy-7-methoxy-3,5-dimethylisochroman-1-one (3), and four known compounds (4–7) were isolated. Their structures were determined using 1D- and 2D-NMR, mass spectrometry, and chemical calculations. The C-3~C-2′ polymerization mode between the two α-naphthalenone derivative moieties is uncommon in compounds 1 and 2. Meanwhile, compounds 1–2 and 5 exhibited antibacterial activity against Bacillus subtilis, Clostridium perfringens, Staphylococcus aureus, and Staphylococcus aureus, with MIC values ranging between 16 and 31 µg/mL. In addition, compound 5 showed antifungal activity against Sclerotinia sclerotiorum and Phytophthora nicotianae var. nicotianae, with respective IC₅₀ values of 88.14 ± 2.21 µg/mL and 52.36 ± 1.38 µg/mL. Compound 1 showed significant cytotoxicity against A2780, PC-3, and MBA-MD-231 cell lines with respective IC₅₀ values of 3.20, 10.68, and 16.30 µM, and the cytotoxicity against A2780 cells was even higher than that of cisplatin (CDDP). With an IC₅₀ value of 10.13 µM, compound 2 also exhibited cytotoxicity against A2780. The in vitro results showed that compound 1 inhibited A2780 cell proliferation, induced apoptosis, and arrested the cell cycle at the S-phase in a concentration-dependent manner.

Dermatan sulfate (DS) accelerates the inhibition of thrombin by heparin cofactor II (HCII). A hexasaccharide consisting of three l-iduronic acid 2-O-sulfate (IdoA2SO₃)→N-acetyl-d-galactosamine 4-O-sulfate (GalNAc4SO₃) subunits was previously isolated from porcine skin DS and shown to bind HCII with high affinity. DS from porcine intestinal mucosa has a much lower content of this disaccharide but activates HCII with potency similar to that of porcine skin DS. Therefore, we sought to characterize oligosaccharides from porcine mucosal DS that interact with HCII. DS was partially depolymerized with chondroitinase ABC, and oligosaccharides containing 2–12 monosaccharide units were isolated. The oligosaccharides were then fractionated by anion-exchange and affinity chromatography on HCII-Sepharose, and the disaccharide compositions of selected fractions were determined. We found that the smallest oligosaccharides able to bind HCII were hexasaccharides. Oligosaccharides 6–12 units long that lacked uronic acid (UA)2SO₃ but contained one or two GalNAc4,6SO₃ residues bound, and binding was proportional to both oligosaccharide size and number of GalNAc4,6SO₃ residues. Intact DS and bound dodecasaccharides contained predominantly IdoA but little d-glucuronic acid. Decasaccharides and dodecasaccharides containing one or two GalNAc4,6SO₃ residues stimulated thrombin inhibition by HCII and prolonged the clotting time of normal but not HCII-depleted human plasma. These data support the hypothesis that modification of IdoA→GalNAc4SO₃ subunits in the DS polymer by either 2-O-sulfation of IdoA or 6-O-sulfation of GalNAc can generate molecules with HCII-binding sites and anticoagulant activity.