Sativene Sesquiterpenoids from the Plant Endophytic Fungus Bipolaris victoriae S27 and Their Potential as Plant-Growth Regulators.

Thirteen new sativene sesquiterpenoids (1 and 3-14), one new natural product (2), and 16 known compounds (15-30) were isolated from the endophytic fungus Bipolaris victoriae S27. Their structures were elucidated by extensive spectroscopic analysis, NMR and ECD calculations, and X-ray crystal diffractions. Compound 1 represented the first example of sativene sesquiterpenoids with a 6/5/3/5-caged tetracyclic ring system. All obtained compounds were evaluated for their plant-growth regulatory activity. The results showed that 1, 3, 4, 6, 8, 11, 12, 17, 19, 26, and 27 could suppress the growth of Arabidopsis thaliana, while 2, 5, 13, 15, 18, and 25 showed promoting effects. Among them, compound 3 showed the most potent plant-growth inhibitory activity, which is obviously superior to that of the marked herbicide glyphosate.

The Natural Alkaloid (-)-N-Hydroxyapiosporamide Suppresses Colorectal Tumor Progression as an NF-κB Pathway Inhibitor by Targeting the TAK1-TRAF6 Complex.

Colorectal cancer (CRC) is an exceptionally deadly disease, whereas effective therapeutic drugs for CRC have declined over the past few decades. Natural products have become a reliable source of anticancer drugs. Previously we isolated an alkaloid named (-)-N-hydroxyapiosporamide (NHAP), which exerts potent antitumor effects, but its effect and mechanism in CRC remain unclear. This study aimed to reveal the antitumor target of NHAP and identify NHAP as a promising lead compound for CRC. Various biochemical methods and animal models were used to investigate the antitumor effect and molecular mechanism for NHAP. These results showed that NHAP exhibited potent cytotoxicity, induced both apoptosis and autophagic cell death of CRC cells, and inhibited the NF-κB signaling pathway by blocking the interaction of the TAK1-TRAF6 complex. NHAP also markedly inhibited CRC tumor growth in vivo without obvious toxicities and possessed good pharmacokinetic characteristics. These findings identify, for the first time, that NHAP is an NF-κB inhibitor with potent antitumor activity in vitro and in vivo. This study clarifies the antitumor target of NHAP against CRC, which will contribute to the future development of NHAP as a novel therapeutic lead compound for CRC.

Neuropyrones A-E, five undescribed α-pyrone derivatives with tyrosinase inhibitory activity from the endophytic fungus Neurospora dictyophora WZ-497.

Five undescribed α-pyrone derivatives, named neuropyrones A-E, were isolated from the endophytic fungus Neurospora dictyophora WZ-497 derived from the stems of Aster tataricus L. f. The structures of these α-pyrones with absolute configurations were determined by comprehensive spectroscopic analysis and computational calculations. All isolated compounds were tested for various bioactivities, including tyrosinase inhibitory activity. The results showed that neuropyrones A-C displayed potent inhibitory effects on tyrosinase with IC50 values of 0.38 ± 0.07, 0.49 ± 0.06, and 0.12 ± 0.01 mM, respectively, which were comparable to that of the positive control, kojic acid (IC50 = 0.14 ± 0.021 mM). A molecular docking study revealed the interaction between 3 and the His263, His85, Val283, Asn260, Phe264, and Val248 residues of tyrosinase.

[Simultaneous determination of ergosterol, nucleosides and their bases from natural and cultured Cordyceps by pressurized solvent extraction and high performance liquid chromatography].

AIM: To establish a simple method for simultaneous determination of ergosterol, nucleosides and their bases in Cordyceps by HPLC coupled with pressurized solvent extraction (PSE). METHODS: The extraction was performed by using PSE and the PSE condition was optimized by using orthogonal test, the contents of ergosterol, nucleosides and their bases in Cordyceps were determined by HPLC. RESULTS: The optimized condition of PSE extraction for ergosterol, nucleosides and their bases in Cordyceps was obtained as follow: solvent, methanol; temperature, 160 degrees C; static extraction time, 5 min; pressure, 10 MPa and one extraction cycle and one time. A ZORBAX NH2 column (250 mm x 4.6 mm ID, 5 microm) and a ZORBAX NH2 guard column (12.5 mm x 4.6 mm ID, 5 microm) were used for simultaneous determination of ergosterol, nucleosides and their bases. Solvents that constituted the mobile phase were A (acetonitrile) and B (10 mmol x L(-1) ammonium acetate in water). The elution conditions applied were: 0 -5.0 min, linear gradient 0 --> 15% B; 5.0-25.0 min, linear gradient 15% --> 20% B; 25.0 - 35.0 min, linear gradient 20% --> 40% B; 35.0 - 45.0 min, linear gradient 40% --> 80% B; 45.0 -50.0 min, 80% B isocratic. The flow-rate was 0. 6 mL x min(-1) and the injection volume was 20 microL. The system operated at 25 degrees C. Ergosterol was monitored and quantified at 275 nm, nucleosides and their bases at 254 nm. CONCLUSION: High performance liquid chromatography coupled with pressurized solvent extraction is a rapid and simple method for simultaneous determination of ergosterol, nucleosides and their bases in Cordyceps.