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Abstract: The total phenolic content of 31 species of fern plants was determined, and their antioxidant activities were assessed by DPPH radical scavenging analysis. [Copyright &y& Elsevier]

The aim of this work is to explore the effects of herbal medicine on secondary metabolites of microorganisms during fermentation. Clonostachys rogersoniana was found to metabolize only small amounts of polyketide glycosides rogerson B and C on fresh potatoes, but after replacing the medium to the medicinal plant Rubus delavayi Franch., the type and content of the metabolized polyketones showed significant changes. The sugars and glycosides in R. delavayi are probably responsible for the changes in secondary metabolites. Six polyketide glycosides including a new metabolite, rogerson F, and two potential antitumor compounds, TMC-151C and TMC-151D, were isolated from the extract of R. delavayi fermented by C. rogersoniana. In addition, 13C labeling experiments were used to trace the biosynthesis process of these compounds. TMC-151C and TMC-151D showed significant cytotoxic activity against PANC-1, K562 and HCT116 cancer cells but had no obvious cytotoxic activity against BEAS-2B human normal lung epithelial cells. The yields of TMC-151C and TMC-151D reached 14.37 ± 1.52 g/kg and 1.98 ± 0.43 g/kg, respectively, after fermentation at 28 °C for 30 days. This is the first study to confirm that herbal medicine can induce microbes to metabolize active compounds. And the technology of fermenting medicinal materials can bring more economic value to medicinal plants. [Display omitted] • Secondary metabolites of microorganisms can be affected by herbal medicine. • TMC-151 s were enriched by fermentation of R. delavayi with C. rogersoniana. • The yields of TMC-151C and TMC-151D reached 14.37 ± 1.52 and 1.98 ± 0.43 g/kg. • Biosynthetic pathways of TMC-151 s were predicted by 13C labeling experiments. [ABSTRACT FROM AUTHOR]

Six new sesquiterpenes, fusarchlamols A-F (1 , 2 , 4 – 7); one new natural product of sesquiterpenoid, methyltricinonoate (3); and ten known compounds were found from Fusarium sp. cultured in two different media by the one strain many compounds strategy. The compounds (1 , 2 , and 4 – 11) were isolated from Fusarium sp. in PDB medium, and compounds (3–5 , 8 , and 10 – 17) were discovered from Fusarium sp. in coffee medium. Additionally, the configuration of 8 was first reported in the research by Mosher's method. The structures were established by 1D, 2D NMR, mass spectrometry, calculated ECD spectra, and Mosher's method. Compounds 1 , 2 , 6 / 7 , 12 , and 16 indicated significant antifungal activities against the phytopathogen Alternaria alternata isolated from Coffea arabica with MICs of 1 μg/mL. The investigation on the anti-phytopathogen activity of metabolites can provide lead compounds for agrochemicals. [Display omitted] [ABSTRACT FROM AUTHOR]

Two new pyranonaphthoquinones, phialoyxinones A (1) and B (2), a new eighteen-membered ring lactone, phialoyxtone (3), and five known pyranonaphthoquinone derivatives were identified from the fungus Phialocephala sp. YUD18001, which was isolated from the rhizospheric soil associated with Gastrodia elata. Their structures were unequivocally established by a comprehensive interpretation of the spectroscopic data, with the stereochemistry for 1 – 3 was defined by a combination of TDDFT calculations, and the DP4+ probability analysis based on NMR chemical shift calculations. All of the new compounds 1–3 were evaluated for cytotoxicity and acetylcholinesterase inhibitory, compound 2 exhibited in vitro cytotoxic activities against five human cancer cell lines (HL-60, SMMC-7721, A549, MCF-7 and SW480) with IC 50 values ranging from 11.80 to 19.32 μM. Compounds 2 and 3 exhibited moderate AChE inhibitory activities. A putative biosynthetic pathway for the pyranonaphthoquinones was proposed. [Display omitted] • Two pyranonaphthoquinones and an eighteen-membered ring lactone were discovered from Phialocephala sp. YUD18001. • Their structures were characterized by means of extensive spectroscopic analyses and chemical calculations. • Phialoyxinone B showed moderate cytotoxic and AchE inhibitory activities in vitro. [ABSTRACT FROM AUTHOR]

The fungus Nectria sp. MHHJ-3 was isolated from Illigera rhodantha. A molecular networking-guided the secondary metabolites investigation of Nectria sp. MHHJ-3 led to the isolation of ten metabolites (1 − 10), including two new naphthalenone derivatives, nectrianaphthalenones A (1) and B (2), and two new steroids, nectriasteroids A (3) and B (4). Their structures were elucidated by extensive spectroscopic analysis including the HRESIMS, 1D/2D NMR and electronic circular dichroism (ECD) spectra. A plausible biosynthetic pathway for 1 – 2 was proposed. Compounds 1 and 2 exhibited moderate acetylcholinesterase (AChE) inhibitory activities. Compounds 3 and 4 showed significant cytotoxic activity against selected tumor cells. Particularly, compound 3 exhibited the strongest activity against A549 cells with an IC 50 value of 13.73 ± 0.03 μM, which was at the same grade with that of positive control cisplatin. [Display omitted] • Two new naphthalenone derivatives and two new steroids were isolated from the fungus Nectria sp. MHHJ-3. • Molecular networking-guided the secondary metabolites investigation. • Compounds 3 and 4 showed significant cytotoxic activity against selected tumor cells. [ABSTRACT FROM AUTHOR]

Abstract Five new metabolites belonging to two backbones of pulvilloric acid-type azaphilone and tremulane sesquiterpene were obtained and their structures were determined by spectral analysis. Based on the biogenesis analysis, tremulane sesquiterpenes were obtained from Irpex lacteus by the stimulation of mixed-culture. The antifungal selectivities of metabolites produced by fungus against their co-culture fungus and common pathogens , exhibited competitive interaction of this mix-culture. The tremulane sesquiterpene conocenol B produced by I. lacteus through the induction of Nigrospora oryzae showed selectivity of anti-fungal activity against its co-culture fungus, N. oryzae , with MICs at 16 μg/mL and 128 μg/mL against I. lacteus. The fungus can metabolize these new compounds to inhibit the growth of co-culture fungus while not inhibiting its own growth. Compound 5 was active against acetylcholinesterase (AChE) with a ratio of 35% at the concentration of 50 μM. Graphic abstract The antifungal selectivities of new metabolites against its co-culture fungus, produced by different fungus, exhibited the competitive interactions. 5 indicated anti-AChE activity. Unlabelled Image Highlights • The antifungal selectivities of new microbial metabolites against its co-culture fungus showed the competitive interactions. • 5 indicated anti-AChE activity. [ABSTRACT FROM AUTHOR]

Two fungi Aspergillus fumigatus YXG-12-2, and Paraphaeosphaeria sp. YXG-18 were isolated from medicinal plant Ginkgo biloba. The interaction of endophytes and host could induce the productions of antifungal metabolites against pathogens for the plant resistance. Three new fumagillol analogues, fumiparaphines A-C were isolated from A. fumigatus cocultured with Paraphaeosphaeria sp. in host medium. New compounds 2 , and 3 had the similar fumagillol structures with tetrahydrofuran or tetrahydropyrane residue. The structures were established by 1D, 2D NMR, mass spectrometry, and calculated ECD spectra. Fumiparaphine A (1) indicated significant antifungal activity against the phytopathogen Alternaria alternata with MIC of 2 μg/mL. [Display omitted] [ABSTRACT FROM AUTHOR]

Four new cryptic metabolites including one fumagillol derivative (2), one cyclohexenone derivative (4), one 10-membered lactone (5), and one natural 4- epi -brefeldin C (8), along with seven known compounds were found from isogenesis endophytes Aspergillus fumigatus , Penicillium janthinellum , Nigrospora sp., and Stagonosporopsis sp. induced by host Nicotiana tabacum medium and co-culture. The structures were determined mainly by spectroscopic methods, including extensive 1D, 2D NMR, MS techniques, ECD calculation, and Mosher's method. Compound 2 possessed a novel 1, 3-dioxetane residue and cyclohexane-containing terpenoid skeleton. Compounds 2 , 4 – 7 and 10 showed significant antifungal activities against the plant pathogen Nigrospora sp. with MICs of 1 μg/mL. 2 , 4 , 5 – 7 , and 10 indicated antifungal activities against Penicillium janthinellum , Aspergillus fumigatus , Phomopsis sp., and Alternaria sp. with MICs ≤8 μg/mL. Compounds 2 , 6 – 8 , and 10 (50 μg/cm2) and microbial fermentation extracts (100 μg/cm2) showed antifeedant activities against silkworms with feeding deterrence indices of 21–100%. [Display omitted] • Four new cryptic metabolites from four endophytes induced by host tobacco medium and co-culture. • Asperfumol was a novel cyclohexane-containing terpenoid possessing 1, 3-dioxetane residue. • Some of isolated compounds, and extracts indicated significant antifungal, and antifeedant activities. [ABSTRACT FROM AUTHOR]

Six new physalin steroids, 7 β -methoxylisophysalin B ( 1 ), 7 β -methoxylphysalin C ( 2 ), physalin V ( 3 ), physalin VI ( 4 ), physalin VII ( 5 ), isophysalin I ( 6 ), together with 20 known physalins ( 7 – 26 ) were isolated from calyces of Physalis alkekengi var. franchetii . Structures of the new compounds were revealed through 1D and 2D NMR and mass spectroscopic methods. Compounds 1 – 26 were evaluated for cytotoxicity against human HL-60, SMMC-7721, A-549, MCF-7 and SW-480, and the results indicated that compounds 8 , 11 , and 14 displayed potent cytotoxicities (IC 50 < 5 μM) in vitro. Further antibacterial assay indicated that compounds 8 , 14 , and 19 showed high antibacterial activities against Bacillus subtilis and Escherichia coli . [ABSTRACT FROM AUTHOR]

Two new peroxy fatty acids, thermalic acids A ( 1 ) and B ( 2 ), together with eight known compounds, (3 β )-methyl-3-hydroxy-urs-11-en-28 oate ( 3 ), luteolin ( 4 ), quercetin ( 5 ), 3-methoxyquercetin ( 6 ), ophioglonol ( 7 ), ophioglonol 4′-O- α -D-glucopyranoside ( 8 ), pedunculosumoside B ( 9 ), syringol ( 10 ), were isolated from the herba of Ophioglossum thermale Kom. The structures of 1 and 2 were identified by HRESIMS, EIMS, 1D and 2D NMR, and electronic circular dichroism (ECD) spectra. Both two acids exhibited potential antibacterial activities against Staphylococcus aureus , Bacillus subtilis , and Escherichia coli . This is the first report of peroxy fatty acids isolated from herbaceous plants of Ophioglossaceae. [ABSTRACT FROM AUTHOR]

An unusual proaporphine alkaloid bearing an isopropanenitrile group at isoquinoline nitrogen, named epiganine A ( 1 ) and a new aporphine alkaloid, epiganine B ( 2 ), together with eight known alkaloids, pronuciferine ( 3 ), dehydrodicentrine ( 4 ), romerine ( 5 ), romeline ( 6 ), N -methylcalycinine ( 7 ), phanostenine ( 8 ), dicentrine ( 9 ), and N -methyllaurotetanine ( 10 ), were isolated from the roots of Stephania epigaea . The absolute configuration of 1 was determined by calculating electronic circular dichroism (ECD) and comparing with experimental data. Compounds 2 and 4 showed strong acetylcholinesterase (AChE) inhibitory effects with the IC 50 values of 4.36 and 2.98 μM, respectively. Compounds 5 – 9 also exhibited potent AChE inhibitory activities. [ABSTRACT FROM AUTHOR]

One new phenanthrene, aphyllone A ( 1 ) and four new bibenzyl derivatives, aphyllone B ( 2 ) and aphyllals C–D ( 3 – 5 ), together with nine known compounds ( 6–14 ), were isolated from the stems of Dendrobium aphyllum (Roxb.) C. E. Fischer. The structures of these new compounds were elucidated by means of extensive spectroscopic analyses, and the absolute configuration of compound 1 was determined by single crystal X-ray diffraction and quantum calculations. Compounds 6 , 8 and 14 inhibited NO production at the concentration of 25 μM in LPS-stimulated RAW264.7 cells with the inhibition (%) of 32.48, 35.68, and 38.50. Compound 2 possessed significant DPPH radical scavenging activity with scavenging percentage of 87.97% at the concentration of 100 μg/mL. [ABSTRACT FROM AUTHOR]

The investigation of the metabolites from endophyte Irpex lacteus cultured in host "tian ma" (Gastrodia elata) revealed five new tremulane sesquiterpenes (1 – 5), and a new tetrahydrofuran derivative (6). Compound 1 was the first tremulane glucoside, and 6 possessed a rare tetrahydropyran-tetrahydrofuran scaffold. Main metabolite (2,3-dihydroxydodacane-4,7-dione , 14) from I. lacteus showed significant selectivity for antifungal activity against phytopathogen and endophytes associated with G. elata rather than against Armillaria sp. providing nutrition for the host G. elata. 14 accounted for 27.4% of isolated compounds from G. elata medium, and 69.3% by co-culturing with Armillaria sp. So the I. lacteus tended to promote the growth of Armillaria sp. in co-culture by producing 2,3-dihydroxydodacane-4,7-dione (14) to selective inhibit the phytopathogen and endophyte existed in host G. elata for the benefit of G. elata - Armillaria symbiosis. And the results were in accord with the real environment of G. elata depending on the nutrition of Armillaria. Some metabolites had anti-fungal activities against phytopathogens of G. elata with MICs ≤8 μg/mL. [Display omitted] [ABSTRACT FROM AUTHOR]

Three new dihydrophenanthrenes, retusiusine D (1), retusiusine E (2), retusiusine F (3), and a new phenanthrene retusiusine G (4), together with two known dihydrophenanthrenes 4,7-dihydroxy-2,3-methylenedioxy-9,10-dihydrophenanthrene (5) and epemeranthol-A (6) were isolated from the tubers of Bulbophyllum retusiusculum. Their structures were established on the basis of extensive spectroscopic analyses. Compounds 1 and 2 exhibited potent cytotoxic activities against SMMC-7721 and weak cytotoxic activities against HL-60. Compound 4 showed moderate cytotoxic activity against SMMC-7721 and MCF-7. [Display omitted] [ABSTRACT FROM AUTHOR]

Five new tremulane sesquiterpenoids were isolated from co-culture of endophyte Irpex lacteus , phytopathogen Nigrospora oryzae , and entomopathogen Beauveria bassiana. All compounds showed obvious antifeedant activities against silkworm with inhibition percentages of 73–99%, at concentrations of 50 μg/cm2. Compound 11 indicated notable antifeedant activity with inhibition percentage of 93% at concentration of 6.25 μg/cm2 among them. Compounds 2 , 3 , 4 , 8 , 9 , 15 and 16 indicated anti-fungal activities against I. lacteus with MIC values ≤8 μg/mL, compounds 11 , 12 , 16–18 showed significant anti-fungal activity against N. oryzae with MICs ≤ 4 μg/mL, and compounds 2 , 5 , 12 and 18 indicated significant anti-fungal activity against B. bassiana with MICs ≤ 8 μg/mL. In addition, the I. lacteus should unite B. bassiana to inhibit the production of phytotoxins from N. oryzae in the ternary culture. Unlabelled Image [ABSTRACT FROM AUTHOR]

Penctrimertone (1), a novel citrinin dimer bearing a 6/6/6/6 tetracyclic ring scaffold, along with two known compounds xerucitrinic acid A (2) and citrinin (3) were isolated from the endophytic fungus Penicillium sp. T2-11. Their structures were unequivocally established by a comprehensive interpretation of the spectroscopic data, with the stereochemistry for 1 was defined by a combination of TDDFT-ECD calculations and the DP4+ probability analysis based on NMR chemical shift calculations. Bioassays revealed that compound 1 exhibited noticeable antimicrobial activities and moderate cytotoxicity. A plausible biosynthetic pathway of 1 was also proposed. Unlabelled Image • A novel citrinin dimer from a Penicillium fungus associated with Gastrodia elata. • Penctrimertone features a novel 6/6/6/6 tetracyclic ring scaffold. • The stereochemistry was elucidated by DP4+ and TDDFT-ECD calculation methods. • Penctrimertone showed noticeable antimicrobial activities and moderate cytotoxicity. [ABSTRACT FROM AUTHOR]

Peniterester (1), a new tricyclic sesquiterpene, together with 6 known compounds (2 – 7) were isolated from the secondary metabolites of an artificial mutant Penicillium sp. T2-M20 which was obtained from the parental strain Penicillium sp. T2–8 via UV irradiation as well as nitrosoguanidine (NTG) induction. Peniterester was only produced by the mutant T2-M20 on the basis of LC-MS analysis. Meanwhile, the results of in vitro bioactivities screening indicated that peniterester owned obvious antibacterial activities against Bacillus subtilis , Escherichia coli and Staphylococcus aureus with MICs of 8.0, 8.0 and 4.0 μg/mL, respectively. Unlabelled Image [ABSTRACT FROM AUTHOR]