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Seven new merosesquiterpenoids, trichothecrotocins D-J (1-7), two new trichothecene sesquiterpenoids, trichothecrotocins K (12) and L (13), and six known compounds (8-11, 14, and 15), were isolated from a potato-associated fungus, Trichothecium crotocinigenum. Compounds 5 and 6 were racemates which were further separated as pure enantiomers. Structures together with absolute configurations were established by extensive spectroscopic analysis, as well as quantum chemistry calculations on ECD and optical rotations. Compounds 1-4 are rare meroterpenoids featuring a seco-phenyl group, while 1 and 2 possessed a novel 6-6/5 fused ring system. Compounds 1-4, 8, 11, and 12 showed antifungal activity against four plant pathogens with MIC values of 8-128 μg/mL. It is suggested that the meroterpenoids produced by T. crotocinigenum may play an important role in the antifungal property of the fungus, thereby protecting the host plant, i.e., potato.

Three undescribed bisabolane sesquiterpenoids, zopfiellins A–C (1‒3), and one new α-pyrone derivative, zofiellone (4), have been isolated from cultures of the endophytic fungus Zopfiella sp. Compound 2 is a rare trinor-bisabolane sesquiterpenoid and 3 has an unusual aromatic core. Compounds 3 and 4 possess mild cytotoxicities against three human cancer cell lines with a range of IC50 values from 12.3–27.3 μM.

Two previously undescribed cadinane-type sesquiterpenoids, rigidoporones A and B (1 and 2), along with an undescribed racemic indolizine alkaloid, (±)-rigidoporine A (3), were isolated from the rice fermentation of the wood-decay fungus Rigidoporus microporus. The structures of the compounds were established by extensive spectroscopic methods, including 1D & 2D NMR and HRMS spectroscopic analysis. Compounds 1 and 3 were evaluated for their inhibitory activity on NO production in murine monocytic RAW264.7 macrophages (IC50 > 25 μM).

Two undescribed piperidine racemates, (±)-caulophines A and B (1 and 2), a new N-containing xanthone derivative (3), together with six known piperidines, were isolated from the roots of Caulophyllum robustum Maxim. Their structures were determined by extensive spectroscopic techniques. Compounds 3 and 7 exhibited weak cytotoxicities against human palace cancer hela cell line with inhibitory rates of 32.2% and 39.7%, respectively, at the concentration of 40 μM.

Two undescribed triterpenes, tricholimbrins A and B, three undescribed steroids, tricholimbrins C‒E, one undescribed 4-chromanone derivative, along with 27 known compounds were isolated from fruiting bodies of the mushroom Tricholoma imbricatum. Tricholimbrins A and B are two polycyclic triterpenoids with a carbon degradation, while tricholimbrin C is a ring-rearranged steroid containing an aromatic moiety that might be derived from an ergosterol. Isocyathisterol, 3β,15α-dihydroxyl-(22E,24R)-ergosta-5,8(14),22-trien-7-one, demethylincisterol A3, and volemolide showed cytotoxicities to six human cancer cell lines. 3β-Hydroxyl-(22E,24R)-ergosta-5,8,22-trien-7,15-dione and 3β-hydroxyl-(22E,24R)-ergosta-5,8,22-trien-7-one showed preferable cytotoxicities against HL-60 while chaxine C and volemolide showed preferable cytotoxicities against A-549, with IC50 values less than 10 μM.

A new lupane triterpenoid, 23-O-trans-feruloylcylicodiscic acid (1), as well as four known analogues (2‒5), was isolated from the EtOAc fraction of Menyanthes trefoliata. The structure of compound 1 was elucidated on the basis of extensive spectroscopic analysis, including 2D NMR data. The structures of the known compounds were established by comparison of their spectroscopic data with that in the literature. Compounds 1, 2, and 4 exhibited certain anti-NO production activities.

Antroalbocin A (1), a sesquiterpenoid possessing a bridged tricyclic system, was isolated from cultures of the higher fungus Antrodiella albocinnamomea (Basidiomycota). The structure with the absolute configuration was determined by extensive spectroscopic methods and single-crystal X-ray diffraction. A plausible biosynthetic pathway for 1 was proposed. Compound 1 was found to inhibit Staphylococcus aureus with an MIC value of 169 μM.

Seven previously undescribed trichothecenes, named trichothecrotocins M–S (1–7), along with five known compounds, were isolated from rice cultures of the potato-associated fungus Trichothecium crotocinigenum. Their structures and absolute configurations were determined through spectroscopic methods, single-crystal X-ray diffraction, and quantum chemistry calculations on ECD. Compound 1 possesses a rare 6,11-epoxy moiety in the trichothecene family. Compound 6 exhibited strong cytotoxic activity against MCF-7 cancer cell lines with an IC50 value of 2.34 ± 0.45 μM. It promoted apoptosis induction in MCF-7 cells. Moreover, cell cycle analysis showed cell cycle arrest caused by compound 6 at the G2/M phase which resulted to cell proliferation inhibition and pro-apoptotic activity. Further quantitative real-time PCR (qRT-PCR) analysis confirmed that the G2/M arrest was accompanied by upregulation of p21 and down regulation of cyclins B1 in 6-treated MCF-7 cells.

The chemical constituents and their biological activities of the mushroom Pyropolyporus fomentarius were investigated in this study. Two previously undescribed pentacyclic lupane-type triterpenes, 3-formyloxybetulin and 3-formyloxybetulinic acid, two rare degraded ergosterols, pyropolincisterols A and B, along with ten known triterpenoids and four known ergosterols were isolated from the fruiting bodies of P. fomentarius. Their chemical structures were determined using a combination of spectroscopic analysis. Nine compounds exhibited certain cytotoxicities to human cancer cell lines, while polyporenic acid showed significant cytotoxicities to SMMC-7721 and A-549 with IC50 values less than 10 μM. Four compounds showed inhibitory activities against nitric oxide (NO) production in LPS-activated RAW264.7 macrophages with IC50 values of 36.3, 25.1, 21.4, and 34.2 μM, respectively. The results of this assessment suggested that the lanostane triterpenoids and ergosterols in fruiting bodies of P. fomentarius played key roles in its folk usages.

Three new indole alkaloids, ophiorrhines C–D (1–3), together with one known analogue, have been isolated from the plant of Ophiorrhiza cantoniensis Hace. The structures of the new alkaloids with the absolute configurations were elucidated by means of spectroscopic methods, electronic circular dichroism (ECD) and calculated nuclear magnetic resonance (NMR) with DP4+ analysis. Compounds 1 and 2 exhibited certain activity to Con-A induced T cell proliferation, and 1 exhibited good inhibition on LPS-induced B cell proliferation with an IC50 value of 8.7 μM.

Three depsidones boremexins A–C (1–3), two diaryl ethers boremexins D (4) and E (5), together with four known compounds were obtained from cultures of potato endophytic fungus Boeremia exigua. Their structures with absolute configurations were established by extensive spectroscopic methods and electronic circular dichroism (ECD) calculations. Compounds 1–4, 6, and 9 displayed anti-inflammatory properties on nitric oxide production in LPS-induced RAW264.7 macrophages with an IC50 range of 19.4–34.4 μM. Compounds 2 and 5 exhibited cytotoxicities to human breast cancer cell line (MCF–7) with IC50 values of 33.1 and 4.0 μM, respectively.

Two trichothecene sesquiterpenoids, trichothecrotocins A (1) and B (2), and a merosesquiterpenoid racemate, (±)-trichothecrotocin C (3), were obtained from potato endophytic fungus Trichothecium crotocinigenum by bioguided isolation. Their structures were elucidated by extensive spectroscopic methods, electronic circular dichroism calculations, and single-crystal X-ray diffraction. Compounds 1 and 2 are trichothecenes possessing new ring systems. Compound 3 possesses a novel 6/6-5/5/5 fused ring system. Compounds 1-3 showed antiphytopathogenic activities with MIC values of 8-128 μg/mL.

A new homoisoflavonoid, (3R)-5,7-dihydroxy-6-methyl-3-(2′-hydroxy-4′-methoxybenzyl)-chroman-4-one (1), namely polygonatone H, in addition to fourteen known homoisoflavones (2–15) were isolated from the rhizome of Polygonatum Cyrtonema Hua. The structures were identified with the aid of 1D/2D NMR spectroscopic technologies. Compounds 2, 6, 8, 10, 11, 13, and 15 were isolated from P. Cyrtonema for the first time. Compound 1 showed cytotoxicities to human cancer cell lines with IC50 values to comparable those of cisplatin.