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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]

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]