An anti-herpes simplex virus-type 1 agent from Xylaria mellisii (BCC 1005)

A structurally unique polyketide, mellisol (1) and 1,8-dihydroxynaphthol 1-O-α-glucopyranoside (3), were isolated from the fungus Xylaria mellisii (BCC 1005). The relative stereostructure of 1 was determined on the basis of X-ray crystallographic data. Compounds 1 and 3 exhibited activity against herpes simplex virus-type 1 with IC₅₀ values of 10.50 and 8.40 μg/mL, respectively. They also showed cytotoxic activity against vero cells at the concentration of 40-50 μg/mL.     

Bioactive PKS–NRPS Alkaloids from the Plant-Derived Endophytic Fungus Xylaria arbuscula

A novel hybrid PKS–NRPS alkaloid, xylarialoid A (1), containing a 13-membered macrocyclic moiety and [5,5,6] fused tricarbocyclic rings, together with ten known cytochalasins (2–11), was isolated from a plant-derived endophytic fungus, Xylaria arbuscula. The chemical structures of all compounds were elucidated using 1D and 2D NMR, HR ESIMS spectroscopic analyses, and electronic circular dichroism (ECD) calculation. Compounds 1–3 and 10 exhibited significant antitumor activities against A549 and Hep G2 cell lines, with IC₅₀ values of 3.6–19.6 μM. In addition, compound 1 showed potent anti-inflammatory activity against LPS-induced nitric oxide (NO) production in macrophage RAW 264.7 cells (IC₅₀, 6.6 μM).     

Four New Terpenoids from Xylaria sp. 101

One new diterpenoid, xylarenolide ( 1 ), and three new sesquiterpenoids, xylaranol A ( 2 ), xylaranol B ( 3 ), and xylaranic acid ( 4 ), were obtained from the fungal strain Xylaria sp. 101, which was isolated from the fruiting body of Xylaria sp. collected in Gaoligong Mountain, Yunnan Province. Their structures were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR experiments, and by HR‐Q‐TOF mass spectrometry. Their antimicrobial activities were evaluated.     

New Cytochalasins from the Marine‐Derived Fungus Xylaria sp. SCSIO 156

Two new cytochalasins, 18‐deoxycytochalasin Q ( 1 ) and 21‐O‐deacetylcytochalasin Q ( 2 ), together with four known analogues, cytochalasin Q ( 3 ), 19,20‐epoxycytochalasin Q ( 4 ), 21‐O‐deacetyl‐19,20‐epoxycytochalasin Q ( 5 ), and cytochalasin D ( 6 ), were isolated from the fungus Xylaria sp. SCSIO156 originated from the South China Sea marine sediment. The structures of 1 and 2 were elucidated by MS and 1D‐ and 2D‐NMR data analyses, and comparison with known compounds. The known compounds 3 – 6 were identified by comparison of their MS and NMR data with those reported in the literature. In the in vitro antitumor assay, compounds 2 – 6 showed mild cytotoxicity against three tumor cell lines (MCF‐7, SF‐268, and NCI‐H460).     

A new amino amidine derivative from the wood-decaying fungus Xylaria cf. cubensis SWUF08-86

The secondary metabolites of Xylaria cf. cubensis SWUF08-86 fungus were investigated, and the chromatographic separation of the crude extracts yielded seventeen compounds. The structure elucidation by spectroscopic analysis including 1D and 2D NMR and the comparison of these data with literature, along with HREIMS spectrometry, revealed one new amino amidine derivative (1), together with five known simple cyclic dipeptide analogs, diketopiperazines (2–6) and eleven other known compounds, including one hemi-cycline (10), three aromatic derivatives (11–13), one sesquiterpene (14) and three sterols (15–17). The isolated compounds were screened for anticancer and anti-pathogenic bacterial and fungal activities. Based on this work, Xylaria cf. cubensis SWUF08-86 has proven to be a diverse secondary metabolites producer.     

Chemical Constituents from Termite‐associated Xylaria acuminatilongissima YMJ623

Three previously unreported benzofurans, namely acumifurans A–C ( 1 – 3 ), along with five known compounds, 2‐(isopropyl‐1′‐ol)‐2,3‐dihydrobenzofuran‐5‐carbinol ( 4 ), fomannoxin alcohol ( 5 ), fomannoxin ( 6 ), acremine S ( 7 ) and cyclo(L ‐Pro‐L ‐Leu) ( 8 ), were isolated from the ethyl acetate extracts of the fermented broths of termite n est associated Xylaria acuminatilongissima YMJ623. Compound 4 , a synthe tic benzofuran analogue of 1 – 3 , was isolated for the first time from natural resources. The str uctures of 1 – 8 were determined through spectroscopic data analyses. The absolute configurations of 1 – 4 were established based mainly on ROESY experiment and Mosher’s reaction, and compared the optical rotation data with the literatures. The effects of these compounds on the inhibition of NO production in lipopolysaccharide (LPS)‐activated murine macrophage RAW264.7 cells were also evaluated. Of the compounds tested, 6 showed a mild NO production inhibitory activity without any cytotoxicity, and its mean maximum inhibition (E_max) at 100 μM was 42.98±0.87 %.     

白蚁菌圃上小白球菌和炭角菌的生态关系初报

通过人工调节pH, CO:分压、温湿度以及有机氮等条件,探讨了白蚁巢内两种优势真菌的生态关系.结果表明:小白球菌和炭角菌除对温湿度要求相似外,不同之处在于小白球菌适应于高浓度COZ、低pH值(3.8一4.2),低浓度有机氮,以及对酵母浸膏也有一定的要求。而炭角菌要求低浓度CO, ,高pH值(5.0- 6.3),又需要高浓度有机氮.根据这些实验,我们初步认为白蚁的存在产生了丰富的有机酸和高浓度CO z,可能给小白球菌造成了特定的pH环境,成为蚁巢菌圃上优势真菌的主要选择因子,在“废巢”菌圃上,有机酸和COZ浓度的降低,炭角菌分泌的代谢物质引起菌圃pH值的上升,可能是炭角菌成为优势种的原因。     

A new phthalide from the endophytic fungus Xylaria sp. GDG-102

A new phthalide derivative, xylarphthalide A (1), along with two known compounds (-)-5-carboxylmellein (2) and (-)-5-methylmellein (3), were isolated from the endophytic fungus Xylaria sp. GDG-102 cultured from the Chinese medicinal plant Sophora tonkinensis. Their structures were identified by MS and NMR experiments, and the absolute configuration of 1 was further confirmed by single-crystal X-ray diffraction analysis. Compound 1–3 showed antibacterial activities against Bacillus megaterium, Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Shigella dysenteriae with MIC values of 12.5–25 μg/mL.     

1H and 13C NMR assignments for two new xanthones from the endophytic fungus Xylaria sp. FRR 5657

The complete 1H and 13C NMR assignments are reported for the new natural products, 7-hydroxy-3-(hydroxymethyl)-1-methoxy-9H-xanthen-9-one (1) and 2,5-dihydroxy-8-methoxy-6-methyl-9-oxo-9H-xanthene -1-carboxylic acid (2). Both of these secondary metabolites were isolated from the fermentation culture of the endophytic fungus Xylaria sp. FRR 5657. 1D and 2D NMR experiments that included 1H, gCOSY, gHSQC and gHMBC were used for the determination of the structure and assignment of these xanthones.     

Seven Novel Linear Polyketides from Xylaria sp. NCY2

Seven novel polyketides, namely, 1‐(xylarenone A)xylariate A ( 1 ), xylarioic acid B ( 2 ), xylariolide A ( 3 ), xylariolide B ( 4 ), xylariolide C ( 5 ), methyl xylariate C ( 6 ), and xylariolide D ( 7 ), together with the known one taiwapyrone ( 8 ), were isolated from the endophytic fungal strain Xylaria sp. NCY2 of Torreya jackii Chun . Their structures were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR experiments, and on the basis of HR‐Q‐TOF mass spectrometry. Antitumor and antibacterial assays of compounds 1 – 8 were carried out, which show moderate activities.