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The temperature-sensitive inverse macroporous membranes containing thermo-responsive poly (N-isopropylacrylamide) (PNIPAM) were prepared by a template of silica microspheres. The inverse membranes ...

In this paper, the adsorption of copper ions on the prepared multilayer diazo resin-graphene oxide/polyacrylonitrile composite membranes was studied, and the adsorption capacity of GO modified poly...

PAN hollow fiber functional membrane with heavy metal ion adsorption capacity was prepared via layer-by-layer method using diazo-resin (DR). Ethylenediaminetetraacetic acid (EDTA) and graph...

Highly permeable pocket-shaped microfiltration membranes with binary porous structures, which are composed of brominated poly(2,6-dimethyl-1,4-phenylene oxide) (BPPO), were prepared on needles by breath figure (BF) and colloidal crystal template (CCT) methods. In colloidal crystal templates, the membrane pore size in the bottom layer was adjusted by SiO2 microsphere diameter in the colloidal crystal template, while that in the top layer was adjusted by changing the BPPO concentration. The permeability of the binary porous membrane prepared by BF and CCT methods was higher than that of membranes only prepared by the BF method. Due to high permeability and antifouling properties, the pocket shaped binary porous membrane was connected to a syringe and used as a filter film in microfiltration and sample preparation fields.

Fullerene (C60) was successfully grafted on cellulose following with the modification of cellulose by acid chlorination and subsequently azidation. The structures of modified cellulose made by sulf...

The metabolite profiles and antioxidant activity of Dendrobium catenatum Lindley leaf, a new functional ingredient for food product development, were evaluated in samples that had been prepared using various methods, including freeze-drying, hot-air drying, rolling before drying, steaming before drying, steaming and rolling before drying, and drying at 100, 80, and 60 °C. The concentrations of polysaccharides and flavonoids, as well as the antioxidant capacity of each sample, were determined. Furthermore, two nucleosides, four amino acids, one monoaromatic compound, and eight flavonoids were identified in dried leaves using high-performance liquid chromatography–diode array detector–electrospray ionization–multistage mass spectrometry (HPLC-DAD-ESI-MSn) and ultraviolet (UV) spectral analyses. The content of polar compounds such as cytidylic acid, arginine, tyrosine, and hydroxybenzoic acid hexose increased dramatically during hot-air-drying and rolling-before-drying treatments, while flavonol C-glycosides remained stable throughout the various treatments and drying temperatures. Rolling before drying at 100 °C was identified as the most suitable process when manufacturing tea products from D. catenatum leaves. This process resulted in a high-antioxidant-activity and visually appealing tea. This report details a potential strategy that should be applied in the manufacturing processes of high-quality products from D. catenatum leaves.

Advanced modified polyacrylonitrile (PAN) membrane with high adsorption property for heavy metal ions was designed and fabricated for the first time. The introduced diazoresin-ethylenediaminetetraacetic acid (DR-EDTA) layer could effectively absorb the metal ion, such as Cu2+, Pb2+, Hg2+ in the waste water. The effects of layers, metal ion concentration, pH, temperature and cycle time were investigated. The results showed that the adsorption isotherms for Cu2+ were well fitted by Langmuir model. The maximum adsorption capacity of the modified membrane for Cu2+ was approximately 47.6 mg/g. In addition, the prepared PAN-(DR-EDTA)3 membrane could be regenerated more than 720 h based on their adsorption/desorption cycles. The results demonstrated that the modified PAN membrane could be used as effective adsorbents for heavy metal removal from waste water.

A bioassay-guided in vitro screen has revealed that a 70% methanol extract of the leaves of Salix matsudana shows considerable inhibitory activity against cyclooxygenases (COX-1 and COX-2). A subsequent phytochemical study led to the isolation of a new flavonoid, matsudone A (1), together with five known flavonoids – luteolin (2), isoquercitrin (3), 7-methoxyflavone (4), luteolin 7-O-glucoside (5), 4',7-dihydroxyflavone (6) – and two phenolic glycosides, leonuriside A (7) and piceoside (8). Their structures were elucidated on the basis of extensive 1D- and 2D-NMR studies, high resolution ESI mass spectroscopic analyses and comparisons with literature data. The isolated compounds 1-8 were tested for their inhibitory activities against COX-1 and COX-2. Compounds 1, 5 and 6 were found to have potent inhibitory effect on COX-2 and compounds 3-5 exhibited moderate inhibition against COX-1.

In preliminary experiments, polyphenol fractions prepared from the leaves of Salix matsudana reduced the elevation of the rat plasma triacylglycerol level at 3 and 4 h after oral administration of a lipid emulsion containing corn oil, at a dose of 570 mg/kg. The present study examined the anti-obesity action of polyphenol fractions of S. matsudana leaves by testing whether the polyphenol fractions prevented the obesity induced by feeding a high-fat diet to female mice for 9 weeks. Body weights at 2-9 weeks and the fi nal parametrial adipose tissue weights were significantly lower in mice fed the high-fat diet with 5% polyphenols of S. matsudana leaves than in those fed the high-fat diet alone. The polyphenols of S. matsudana leaves also significantly reduced the hepatic total cholesterol content, which was elevated in mice fed the high-fat diet alone. In addition, the polyphenol fractions of S. matsudana leaves inhibited palmitic acid uptake into brush border membrane vesicles prepared from rat jejunum and alpha-amylase activity, and their fractions enhanced norepinephrine-induced lipolysis in fat cells. In conclusion, it is suggested that the inhibitory effects of the flavonoid glycoside fraction of S. matsudana leaves on high-fat diet-induced obesity might be due to the inhibition of carbohydrate and lipid absorption from small intestine through the inhibition of alpha-amylase and palmitic acid uptake into small intestinal brush border membrane or by accelerating fat mobilization through enhancing norepinephrine-induced lipolysis in fat cells.

Phytochemical study on the BuOH-soluble fraction of the stem bark of Populus davidiana resulted in the isolation of a new salicin derivative ( 1 ), named davidianoside. The structure was elucidated on the basis of extensive physicochemical and spectroscopic analyses.