Objective It is imperative to provide some consistent experimental results for the extraction of flavonid from Fructus Gardeniae.Methods The key extraction parameters that influenced the yield of flavonid from Fructus Gardeniae were optimized by employing an orthogonal experiment [L9(3)4],including the ratio of buffer solution (Na2B4O7·10H2O) to raw material,concentration of Fructus Gardeniae in extracting solution,extraction time and pH of buffer solution.An UV/Vis detector was used to perform the qualitative and quantitative analyses of the extracted flavonid with the using of the standard sample.Results The maximum extraction yield of the crude extract was 5.0533 (mg/g) after 20 min when the mass ratio of Na2B4O7·10H2O to raw material was 0.4%,the concentration of Fructus Gardeniae in the extraction solution was 1/12 (g/mL),and pH of buffer solution was 4.5.The positive reactions to the Molish and HCl‐Mg tests suggested that the extracted compound was flavonoid,and FTIR measurements also identified the presence of flavonoid in the extracts.Conclusion This work is expected to provide a basis for further research,development,and utilization of Fructus gardenia in flavonid extraction.
CAI Ding Jian SHU Qing XU Bao Quan PENG Li Mei HE Yan
A series of Mo-doped ZnO photocatalysts with different Mo-dopant concentrations have been prepared by a grinding-calcination method.The structure of these photocatalysts was characterized by a variety of methods,including N 2 physical adsorption,X-ray diffraction(XRD),scanning electron microscopy(SEM),Fourier transform infrared(FT-IR) spectroscopy,photoluminescence(PL) emission spectroscopy,and UV-vis diffuse reflectance spectroscopy(DRS).It was found that Mo 6+ could enter into the crystal lattice of ZnO due to the radius of Mo 6+(0.065 nm) being smaller than that of Zn 2+(0.083 nm).XRD results indicated that Mo 6+ suppressed the growth of ZnO crystals.The FT-IR spectroscopy results showed that the ZnO with 2 wt.% Mo-doping has a higher level of surface hydroxyl groups than pure ZnO.PL spectroscopy indicated that ZnO with 2 wt.% Mo-doping also exhibited the largest reduction in the intensity of the emission peak at 390 nm caused by the recombination of photogenerated hole-electron pairs.The activities of the Mo-doped ZnO photocatalysts were investigated in the photocatalytic degradation of acid orange II under UV light(λ = 365 nm) irradiation.It was found that ZnO with 2 wt.% Mo-doping showed much higher photocatalytic activity and stability than pure ZnO.The high photocatalytic performance of the Mo-doped ZnO can be attributed to a great improvement in the surface properties of ZnO,higher crystallinity and lower recombination rate of photogenerated hole-electron(e-/h+) pairs.Moreover,the undoped Mo species may exist in the form of MoO3 and form MoO3 /ZnO heterojunctions which further favors the separation of e-/h+ pairs.
YU ChangLinYANG KaiSHU QingYU Jimmy CCAO FangFangLI XinZHOU XiaoChun
