Biogenic C-doped titania templated by cyanobacteria for visible-light photocatalytic degradation of Rhodamine B.

Cyanobacteria, which occurred in eutrophic water harvest solar light to carry out photosynthesis with high efficiency. In this work, cyanobacteria (Microcystis sp.) were used as biotemplate to synthesize titania structure. The synthesized titania sample had similar morphology to that of the original template in spite of the fragile unicellular structures and extremely high water content of cyanobacterial cells. Incorporation of biogenic C, as well as the morphology inherited from biotemplate improved visible-light absorbance of the titania structure. The sample exhibited higher visible-light photocatalytic activity than commercial titania photocatalyst Degussa P25 for Rhodamine B (RhB) degradation. Compared with those C-doped titania photocatalysts prepared by other methods, cyanobacteria templated titania photocatalyst offer some potential for competitive advantages. The reported strategy opened up a new use for the cyanobacteria. It could also be used for titania in applications such as treatment of polluted water, dye-sensitized solar cells, or other regions.

[X-ray fluorescence spectrum studies on bioorganic carbon in cereals and carbon chemical circulation].

The bioorganic carbon contents and chemical element compositions in six kinds of cereals: paddy (rice), wheat (flour), soybean, millet, sorghum and corn were determined by X-ray fluorescence (XRF) spectrum, meanwhile a new method was established to probe their protein contents. In the cereals, the average bioorganic carbon content is about 440%. The highest protein content is 42.74% from soybean, and other protein content is 28.56% in millet, 27.57% in wheat, 24.99% in corn, 22.21% in sorghum, but only 20.31% in rice. Based on our new definition of carbon chemical circulation presented in the current work, the authors have found that in 2009 humankind used bioorganic carbon to discharge CO2 into the earth's atmosphere that accounts for one percent of the total CO2 discharge, and consumed organic carbon to release CO2 into the earth's atmosphere, accounting for 10.73% of the total CO2 discharge. The clear definition of carbon chemical circulation and the discharged CO2 content from the distinct types of carbon compounds would advance the study on carbon chemical circulation and the atmospheric CO2 greenhouse effect. Our work further found that it takes eight years to circulate the total earth's atmospheric CO2. The short period shows the sensitivity for CO2 to keep its dynamical equilibrium in the earth's atmosphere. However, no experimental data has been reported to prove a heavy destructive greenhouse effect of CO2 existing in the earth's atmosphere.

Fe-MIL-101 exhibits selective cytotoxicity and inhibition of angiogenesis in ovarian cancer cells via downregulation of MMP.

Though metal-organic frameworks (MOFs) have inspired potential applications in biomedicine, cytotoxicity studies of MOFs have been relatively rare. Here we demonstrate for the first time that an easily available MOF, Fe-MIL-101, possesses intrinsic activity against human SKOV3 ovarian cancer cells and suppress the proliferation of SKOV3 cells (IC50 = 23.6 µg mL(-1)) and normal mouse embryonic fibroblasts (BABL-3T3, IC50 = 78.3 µg mL(-1)) cells. It was more effective against SKOV3 cells than typical anticancer drugs such as artesunate (ART, IC50 = 96.9 µg mL(-1)) and oxaliplatin (OXA, IC50 = 64.4 µg mL(-1)), but had less effect on normal BABL-3T3 cells compared with ART (IC50 = 36.6 µg mL(-1)) and OXA (IC50 = 13.8 µg mL(-1)). Fe-MIL-101 induced apoptosis of human umbilical vein endothelial cells (HUVECs) via G0/G1 cell cycle arrest and decreased the mitochondrial membrane potential in HUVECs and induced apoptosis. Furthermore, Fe-MIL-101 exhibited stronger antiangiogenic effects in HUVEC cells than antiangiogenic inhibitor (SU5416) via downregulation the expression of MMP-2/9. Our results reveal a new role of Fe-MIL-101 as a novel, non-toxic anti-angiogenic agent that restricted ovarian tumour growth. These findings could open a new avenue of using MOFs as potential therapeutics in angiogenesis-dependent diseases, including ovarian cancer.

A dye-sensitized Pt@UiO-66(Zr) metal-organic framework for visible-light photocatalytic hydrogen production.

A stable photoactive metal-organic framework UiO-66(Zr) sensitized by adsorbed or directly added rhodamine B dye exhibited photocatalytic activity for hydrogen evolution under visible-light illumination (λ≥ 420 nm). Using Pt as a co-catalyst, the adsorbed and directly added dye extremely enhanced the photocatalytic activity to 30 and 26 times the value afforded by bare Pt@UiO-66(Zr), respectively.

In situ synthesis of molecularly imprinted polymers on glass microspheres in a column.

A facile method to fabricate molecularly imprinted polymers (MIPs) on glass microspheres in a column was developed. The column was prepacked with glass microspheres, and then the prepolymerization mixture was injected into the interstitial volume of the column. The polymerization took place in situ and the column could be directly used for high-performance liquid chromatography after the template had been removed. The template consumption was reduced greatly because the prepolymerization mixture just filled the interstitial volume between the glass microspheres in the column. The MIPs obtained exhibited better kinetic properties, higher efficiency, and low back pressure of the column. Emodin imprinted polymers were prepared by this method and were used for solid-phase extraction.

Antiviral compounds from traditional Chinese medicines Galla Chinese as inhibitors of HCV NS3 protease.

Under the guidance of bioassay, the EtOAc extract fraction of the Traditional Chinese Medicine (TCM) Galla Chinese was found to be efficient in inhibiting the NS3 protease of HCV and purified the fraction to get three polyphenol compounds 1,2,6-tri-O-galloyl-beta-D-glucose (1), 1,2,3,6-tetra-O-galloyl-beta-D-glucose (2), and 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (3), which were identified as inhibitors of Hepatitis C Virus (HCV) NS3 protease. Compounds 1, 2, and 3 inhibited HCV NS3 protease with IC50 of 1.89, 0.75, and 1.60 microM, respectively.

Small molecules blocking the entry of severe acute respiratory syndrome coronavirus into host cells.

Severe acute respiratory syndrome coronavirus (SARS-CoV) is the pathogen of SARS, which caused a global panic in 2003. We describe here the screening of Chinese herbal medicine-based, novel small molecules that bind avidly with the surface spike protein of SARS-CoV and thus can interfere with the entry of the virus to its host cells. We achieved this by using a two-step screening method consisting of frontal affinity chromatography-mass spectrometry coupled with a viral infection assay based on a human immunodeficiency virus (HIV)-luc/SARS pseudotyped virus. Two small molecules, tetra-O-galloyl-beta-D-glucose (TGG) and luteolin, were identified, whose anti-SARS-CoV activities were confirmed by using a wild-type SARS-CoV infection system. TGG exhibits prominent anti-SARS-CoV activity with a 50% effective concentration of 4.5 microM and a selective index of 240.0. The two-step screening method described here yielded several small molecules that can be used for developing new classes of anti-SARS-CoV drugs and is potentially useful for the high-throughput screening of drugs inhibiting the entry of HIV, hepatitis C virus, and other insidious viruses into their host cells.