Contributions of Surface Oxidizing Species and Cu to the Antibacterial Activities of CuO with Different Crystalline Structures.

Although precise regulation of the crystalline structures of metal oxides is an effective method to improve their antibacterial activities, the corresponding mechanisms involved in this process are still unclear. In this study, three kinds of cuprous oxide (CuO) samples with different structures of cubes, octahedra, and rhombic dodecahedra (c-CuO, o-CuO, and r-CuO) have been successfully synthesized and their antibacterial activities are compared. The antibacterial activities follow the order of r-CuO > o-CuO > c-CuO, revealing the significant dependence of the antibacterial activities on the crystalline structures of CuO.

Angucyclinones with IDO and TDO inhibitory activities isolated from the actinomycetes Umezawaea beigongshangensis.

Four previously undescribed angucyclinones umezawaones A-D (1-4) were isolated from the liquid cultures of Umezawaea beigongshangensis. Their structures were determined by spectroscopic analyses, single crystal X-ray diffraction, quantum chemical C NMR and electronic circular dichroism calculations. All compounds displayed strong inhibitory activities against indoleamine 2,3-dioxygenase and tryptophan-2,3-dioxygenase in enzymatic assay, especially compound 2.