Cytotoxic tremulanes and 5,6-secotremulanes, four new sesquiterpenoids from a plant-associated fungus X1-2

<p>Two new tremulanes and two new 5,6-secotremulanes, davotremulanes A-D <b>1</b>–<b>4</b>, along with four known compounds <b>5</b>–<b>8</b>, were isolated from the culture extract of X1-2, an unidentified plant-associated fungus, which was isolated from the endangered plant, <i>Davidia involucrate</i> Baill. in Shennongjia District. The structures of new compounds <b>1</b>–<b>4</b> were established on the basis of extensive spectroscopic analysis. Compounds <b>1</b>–<b>8</b> were evaluated for cytotoxic activity to four cancer cell lines, and compounds <b>1</b>, <b>2</b> and <b>5</b> displayed selectively moderate activities to A549 cell line with IC₅₀ at 15.3, 25.2, 35.2 μg/mL.</p

Dehydrocurvularin-loaded mPEG-PLGA nanoparticles for targeted breast cancer drug delivery: preparation, characterization, <i>in vitro</i>, and <i>in vivo</i> evaluation

Dehydrocurvularin (DCV) is a promising lead compound for anti-cancer therapy. Unfortunately, the development of DCV-based drugs has been hampered by its poor solubility and bioavailability. Herein, we prepared a DCV-loaded mPEG-PLGA nanoparticles (DCV-NPs) with improved drug properties and therapeutic efficacy. The spherical and discrete particles of DCV-NPs had a uniform diameter of 101.8 ± 0.45 nm and negative zeta potential of −22.5 ± 1.12 mV (pH = 7.4), and its entrapment efficiency (EE) and drug loading (DL) were ∼53.28 ± 1.12 and 10.23 ± 0.30%, respectively. In vitro the release of DCV-NPs lasted for more than 120 h in a sustained-release pattern, its antiproliferation efficacy towards breast cancer cell lines (MCF-7, MDA-MB-231, and 4T1) was better than that of starting drug DCV, and it could be efficiently and rapidly internalised by breast cancer cells. In vivo DCV-NPs were gradually accumulated in tumour areas of mice and significantly suppressed tumour growth. In summary, loading water-insoluble DCV onto nanoparticles has the potential to be an effective agent for breast cancer therapy with injectable property and tumour targeting capacity.</p

A new cinnamic acid derivative from plant-derived endophytic fungus <i>Pyronema</i> sp.

<p>Ten secondary metabolites (<b>1–10</b>) including a new 4-hydroxycinnamic acid derivatives, methyl 2-{(<i>E</i>)-2-[4-(formyloxy)phenyl]ethenyl}-4-methyl-3-oxopentanoate (<b>1</b>), and nine known compounds (<b>2–10</b>) were isolated from an EtOAc extract derived from a solid rice medium of endophytic fungal strain <i>Pyronema</i> sp. (A2-1 & D1-2). Their structures were elucidated from NMR and HRMS data. All the compounds were tested for antibacterial activity against <i>Mycobacterium marinum</i> ATCCBAA-535. Compounds <b>1</b>, <b>8</b> and <b>9</b> exhibited moderate antibiotic activity with IC₅₀ of 64, 43 and 32 μM, respectively.</p