Two new alkylated furan derivatives with antifungal and antibacterial activities from the plant endophytic fungus Emericella sp. XL029.

Two new alkylated furan derivatives, 5-(undeca-3',5',7'-trien-1'-yl)furan-2-ol (1) and 5-(undeca-3',5',7'-trien-1'-yl)furan-2-carbonate (2), were isolated from the crude extract of the plant endophytic fungus Emericella sp. XL029 associated with the leaves of Panax notoginseng. The anti-agricultural pathogenic fungal assay indicated that compound 1 displayed significant activity against all tested fungi with minimum inhibitory concentrations (MIC) values from 25 to 3.1 µg/mL, while compound 2 displayed activity against all tested fungi except for Rhizoctonia solani and Fusarium oxysporum with MIC values from 50 to 12.5 µg/mL. Furthermore, compounds 1-2 also exhibited significant inhibitory activity against eight of thirteen tested bacteria with MIC values ranging from 50 to 6.3 µg/mL.

Thickness-controlled synthesis of ultrathin Au sheets and surface plasmonic property.

Thickness-controlled synthesis of nanosheets of nonlayered materials is of scientific significance yet greatly underdeveloped because of the lack of controllable means of inducing anisotropic growth of 2D structures. Here we report a novel 2D template-directed synthesis of ultrathin single-crystalline Au nanosheets with well-tuned thicknesses of several to tens of nanometers, large areas (>100 µm(2)), and atomically flat surfaces. The 2D template is composed of hundred-nanometer-thick water layers sandwiched by lamellar bilayer membranes of a self-assembled nonionic surfactant, dodecylglyceryl itaconate, which appears as an iridescent solution as a result of Bragg reflection of visible light from the periodic lamellar planes. The large-area, ultrathin single-crystalline Au nanosheets enable the fabrication of plasmonic devices. For the first time, the property of surface plasmon polaritons on a patterned single-crystalline Au nanosheet was investigated, and a long propagation length approaching the theoretical expectation was found.

Spontaneous growth of free-standing polypyrrole films at an air/ionic liquid interface.

A novel strategy for the one-pot fabrication of free-standing polypyrrole films is presented in this work. The films are spontaneously formed at an air/ionic liquid interface through interface oxypolymerization. The thicknesses of the films are finely controlled from tens to hundreds of nanometers, and the films are uniform and compact. Asymmetrical films with different smoothness on the two sides of the film are also obtained and exhibit different water wettability. This method is extremely simple and does not need any equipment. It may bring about a general methodology for forming free-standing conducting polymer films.