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Ginger (Zingiber officinale、rhizomes have been reported to exhibit multiple efficacies on human health. In this paper，we found that 打-hexane extract from ginger rhizomes (ginger oil) exhibited the inhibiting abilities against monoamine oxidase A (MAO-A) and B (MAO-B)? which catalyze the oxidative deamination of monoamine neurotransmitters, by using an in vitro luminescencebased method. To characterize the compounds responsible for the inhibiting abilities against MAO-A and MAO-B，all fractions from reversed-phase chromatographies were subjected to the luminescence assay. As a result, we isolated five compounds from ginger oil by nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry. The half-maximal inhibitory concentration (IC50) measurement using purified compounds revealed that (i) 6-，8-，and 10-gingerols had strong inhibiting ability against MAO-A，whereas they showed weak inhibiting ability against MAO-B. (ii) IC50 values of 6-，8-，and 10-gingerols against MAO-A were calculated to be 175.7±11.0)iM，54.6士2.0)iM，and 113.4士4.7(iM? respectively, (iii) Furthermore, we revealed that 1-dehydro- [6]-gingerdione (compound 1)and diacetoxy-[6]-gingerdiol (compound 2) were contained in the ginger oil. (iv) The compound 1 showed strong and selective inhibiting ability against MAO-B with IC50 of 6.77士0.45 jiM，which was 10 times stronger than that against MAO-A. (v) rhe compound 2 showed weak inhibiting ability against both MAO-A and MAO-B. These findings suggest that the compound 1 having strong inhibiting ability against MAO-B could lead to the development of functional food materials intended to improve brain function. [ABSTRACT FROM AUTHOR]

It is known that the stability of polypropylene (PP)-based materials is greatly affected by their higher-order structures. In this paper, we examined the influences of spherulite structure and inorganic filler on the dispersion of stabilizers and the degradation spreading with the aid of IR microscopy. It was found that stabilizers tend to concentrate outside of spherulite structure, and that such a heterogeneous dispersion became more prominent with increasing spherulite size. Oxidative degradation concentrated at chemically and mechanically weak spherulite borders, and was faster for larger spherulites. The addition of inorganic filler promoted the volatilization of stabilizers from poorly connected interfaces between PP and filler, thus reducing the lifetime of PP. In this way, the present paper describes the significance of higher-order structures and interfaces for the degradation and stabilization of PP-based materials. [ABSTRACT FROM AUTHOR]

Copolymers of methyl 4-vinylbenzoate or methyl acrylate with styrene were converted to hydrazide-containing polymers by refluxing with hydrazine monohydrate. The resulting polymers were crosslinked by the oxidative coupling reaction ofhydrazide with oxone or diacetoxyiodobenzene. The crosslinked polymers were decrosslinked by the oxidative degradation of the diacylhydrazine linkage with sodium hypochlorite. The carboxyl group produced by decrosslinking was converted to the methyl ester group by the treatment with trimethylsilyldiazomethane to obtain the original copolymers. The recycling process could be repeated. [ABSTRACT FROM AUTHOR]