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Guo D.,Jiangsu University | Zhang Z.,Jiangsu University | Liu D.,Jiangsu University | Zheng H.,Jiangsu Alphay Bio technology Co. | And 2 more authors.
Water Science and Technology | Year: 2014

Recently, as an emerging persistent dissolved organic pollutant (DOP), gallic acid (GA) and its efficient decomposition methods have received global attention. The present work aimed to compare the effect of Aspergillus oryzae 5992 and Phanerochaete chrysosporium 40719 on degradation of different concentrations of GA. The A. oryzae grew well and achieved a GA removal rate up to 99% in media containing 1-4% GA, much higher than P. chrysosporium. The activity of laccase and lignin peroxidase excreted by A. oryzae was higher than that by P. chrysosporium in the presence of GA. Based on the results of high-performance liquid chromatography-electrospray ionization-mass spectrometry, three relevant intermediate metabolites were determined as progallin A, methyl gallate, and pyrogallic acid, implying that A. oryzae could not degrade GA unless the carboxyl in the molecule was protected or removed. In view of the ability of A. oryzae to accommodate a high concentration of GA and achieve a high removal rate, as well as the significantly different enzyme activities involved in GA degradation and the underlying mechanisms between the two fungal strains, A. oryzae is proven to be a superior strain for the degradation of DOP. © IWA Publishing 2014.

Zhang Z.,Jiangsu University | Shi D.,Jiangsu University | Ding H.,Jiangsu University | Zheng H.,Jiangsu Alphay Bio technology Co. | Chen H.,Jiangsu Alphay Bio technology Co.
International Journal of Environmental Science and Technology | Year: 2015

1,8-Dihydroxy anthraquinone is the intermediate usually used in the dye and pharmaceutical industry, and its direct discharge into water results in serious pollution. In the present study, we aimed to remove 1,8-dihydroxy anthraquinone and investigate its biosorption mechanism of anthraquinone onto nonviable Aspergillus oryzae CGMCC5992 biomass. Biosorption data were intuitively described by Langmuir isotherm and the pseudo-second-order kinetic model. According to the Langmuir model, it deduced that the maximum biosorption capacity of 1,8-dihydroxy anthraquinone was 62.82 mg g−1 at 30 °C and pH 3.0. Characterization of the interaction between biosorbent and possible dye-biosorbent was further confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy. Experimental results suggested that A. oryzae biomass as low-cost, environmentally friendly and efficient biosorbent could be successfully employed in the removal of 1,8-dihydroxy anthraquinone from aqueous solution. © 2015, Islamic Azad University (IAU).

Zhang Z.,Jiangsu University | Pang Q.,Jiangsu University | Li M.,Jiangsu University | Zheng H.,Jiangsu Alphay Bio technology Co. | And 2 more authors.
Environmental Science and Pollution Research | Year: 2014

Fresh biomass of Aspergillus oryzae (A. oryzae) CGMCC5992 can effectively remove gallic acid from aqueous solution. To improve the removal rate of gallic acid, this study first identified the important factors affecting the removal rate of gallic acid with univariate analysis, and then used four-factor and three-level Box-Behnken design (BBD) with the removal rate of gallic acid as response value, to obtain the optimum conditions for the removal of gallic acid as follows: 6.95 h treatment time, pH 3.70, 7.07 g/L mycelium volume, and 120.64 mg/L initial concentration of gallic acid. Under such optimized condition, the removal rate of gallic acid approached 99.21 %. HPLC-MS analysis proved that the gallic acid in aqueous solution was completely removed by A. oryzae, rather than being metabolized into its derivatives. Scanning electron microscopy (SEM) indicated that the biomass morphology and surface structure of A. oryzae changed after the adsorption of gallic acid. Thus, the present study has provided an optimal condition for A. oryzae removal of gallic acid in water. © 2014, Springer-Verlag Berlin Heidelberg.

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