Investigation on the Antifungal Ingredients of Saccharothrix Yanglingensis Hhs.015, an Antagonistic Endophytic Actinomycete Isolated from Cucumber Plant

Apple tree canker infected by Valsa mali var. mali is a serious and widely distributed disease in China. Saccharothrix yanglingensis Hhs.015 is an endophytic actinomycete isolated from cucumber roots, and it has been proven that this strain is a promising biocontrol agent on apple tree canker in previous studies. The aim of this study was to elucidate the active ingredients in its metabolites. Two pentaene macrolides, WH01 and WH02, were isolated from strain Hhs.015, and their structures were elucidated based on the extensive spectroscopic analysis. WH01 and WH02 were identified as fungichromin and 1′-deoxyfungichromin, among which WH02 is a novel compound. These two compounds showed strong in vitro and in vivo antifungal activity against V. mali. By comparison of the structures of hyphae cells treated by pure compound and fermentation broth, it has been proven that pentaene macrolides are the main active ingredients in the metabolites of strain Hhs.015. This is the first report on the antifungal activity of fungichromin and its analogs on V. mali, and the 28-member pentaene macrolides were also firstly isolated from the genus of Saccharothrix

The variability of surface radiation fluxes over landfast sea ice near Zhongshan station, east Antarctica during austral spring

Surface radiative fluxes over landfast sea ice off Zhongshan station have been measured in austral spring for five springs between 2010 and 2015. Downward and upward solar radiation vary diurnally with maximum amplitudes of 473 and 290 W m−2, respectively. The maximum and minimum long-wave radiation values of the mean diurnal cycle are 218 and 210 W m−2 for downward radiation, 277 and 259 W m−2 for upward radiation and 125 and −52 W m−2 for net radiation. The albedo has a U-shaped mean diurnal cycle with a minimum of 0.64 at noon. Sea ice thickness is in the growth phase for most spring days, but can be disturbed by synoptic processes. The surface temperature largely determines the occurrence of ice melting. Surface downward and upward long-wave radiation show synoptic oscillations with a 5–8 day period and intraseasonal variability with a 12–45 day period. The amplitudes of the diurnal, synoptic and intraseasonal variability show some differences during the five austral springs considered here. The intraseasonal and synoptic variability of downward and upward long-wave radiation are associated with the variability of cloud cover and surface temperature induced by the atmospheric circulation

Cu Nanoparticles Inlaid Mesoporous Carbon Aerogels as a High Performance Desulfurizer

In the present study, to insert the Cu nanoparticles (NPs) into mesoporous carbon aerogels and first applied it to remove H₂S efficiently. This desulfurizer was made based on the dimensional policy by inserting the Cu NPs on mesoporous carbon aerogels to overcome the sintering problem and improve the activity, which has potential performance at high-temperature catalysis. The obtained desulfurizer was employed for H₂S removal at middle temperature conditions (optimal H₂S adsorption at 550 °C). We explored the optimum doping amount of CuO_<i>x</i>, optimum temperature conditions, and the influence of textural parameters of carbon aerogels. The desulfurizers were characterized by means of field-emission scanning electron microscopy (FESEM), N₂-adsorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), H₂ temperature-programmed reduction (H₂-TPR), and Raman spectra techniques. The results confirmed that the presence of H₂ was unfavorable for sulfidation and obviously shortened the breakthrough time. However, the existence of CO had little impact on the desulfurization and sulfur capacity. In a nutshell, this work could provide a new synthetic route to prepare Cu NPs deep into the lattice of carbon aerogels structure of desulfurizers and understand the desulfurization mechanism