Two new alkaloids produced by Dothideomycetes sp. BMC-101 isolated from the Magnolia grandiflora.

AbstactA total of 16 fungal strains were isolated from fresh leaves and flowers of Magnolia grandiflora and the EtOAc extracts of them were assayed for antitumor activities. Among these, the fungus Dothideomycetes sp. BMC-101 with broad spectrum inhibition was selected for further study. Four alkaloids (1-4) including two new compounds (2-(hydroxyimino)-3-phenylpropanoyl)-L-phenylalanine (1) and 8-Acetyl-bisdethiobis(methylsulfanyl)apoaranotin (4)) were isolated from Dothideomycetes sp. BMC-101. The structure of 1 was characterized with an oxime moiety formed by the condensation of two phenylalanines. To our knowledge, this is the first report on a fungal phenylalanine derivative with an oxime moiety.

Dothideomins A-D, Antibacterial Polycyclic Bisanthraquinones from the Endophytic Fungus Dothideomycetes sp. BMC-101.

Four new bisanthraquinones, dothideomins A-D (1-4), were identified from Dothideomycetes sp. BMC-101, an endophytic fungus isolated from Magnolia grandiflora L. leaves. Their chemical structures were established by NMR analysis, single-crystal X-ray crystallography, and ECD analysis. Dothideomins A-D (1-4) were characterized by an unusual 6/6/6/5/6/3/6/6 octocyclic scaffold (1 and 2) and a 6/6/6/5/6/6/6 heptacyclic scaffold (3 and 4), respectively. All compounds, especially 1 and 3, exhibited potent antibacterial activity with MIC values ranging from 0.4 to 0.8 µg/mL.

Effort of ionic radius on doped style of silver and copper/zinc oxide nanorods for photodegradation of methylene blue.

The homogeneous Cu-ZnO and heterogeneous Ag/ZnO nanorods were synthesised by controlling the ionic radius of Cu and Ag with lattice of ZnO. The structure of Cu-ZnO and Ag/ZnO was investigated by a series of methods. The study of the photoelectric properties suggested both the homogeneously and heterogeneously doped ZnO displayed an increased photocatalytic performance. It was worth noting that the Cu-ZnO and Ag/ZnO composites shown different degradation activities of methylene blue under the visible and UV light irradiation. The data suggested that the Cu species incorporated into the crystal lattice of ZnO nanorods could promote the utilisation of visible light, leading to 2.5- and 2.7-fold increase in the degradation rates compared with Ag/ZnO and ZnO nanorods. However, when UV light was employed, on the one hand, the significant increase of the activity for both Cu-ZnO and Ag/ZnO compared with ZnO was observed and on the other hand, the degradation rate of Cu-ZnO was close to that of Ag/ZnO. The investigation suggested that the metallic Cu in the ZnO crystal lattice could promote the separation of electrons and holes generated by ZnO under visible light. As for the UV light, both doping styles could favour the separation process. The present work could provide a further insight for the design of ZnO-based nanomaterials and development of their applications in environmental catalysis.