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In this study, an aged refuse bioreactor was constructed to remove nitrogen in a mature landfill leachate. The nitrogen removal efficiency and the microbial community composition in the bioreactor were investigated. The results showed that the aged refuse bioreactor removed more than 90 % of total nitrogen in the leachate under the nitrogen loading rate (NLR) of 0.74 g/kg (vs) day, and the total nitrogen removal rate decreased to 62.2 % when NLR increased up to 2.03 g/kg (vs) day. Quantitative polymerase chain reaction results showed that the average cell number of ammoniaoxidizing bacteria in the bioreactor was 1.58×10 8 cells/g, which accounted for 0.41 % of total bacteria. The number of anammox bacteria in the reactor was 1.09×10 8 cells/g, which accounted for 0.27 % of total bacteria. Isotopic 15 N tracing experiments showed that nearly 10 % of nitrogen was removed by anammox. High-throughout 454 pyrosequencing revealed that the predominant bacteria in the bioreactor were Proteobacteria, Chloroflexi, Actinobacteria, Bacteroidetes, and Gemmatimonadetes, including various nitrifiers and denitrifiers with diverse heterotrophic and autotrophic metabolic pathways, supporting that nitrogen was removed through different pathways in this aged refuse bioreactor.

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The contents of total flavonoid(TF) and total phenolic acid(TPA) in ethanol extracts from bamboo leaves of 21 species of Phyllostachys were determined, and the scavenging effects of ethanol extracts from bamboo leaves on DPPH and ABTS were also studied. The results showed that the ethanol extracts from bamboo leaves of 20 species of Phyllostachys contained rich flavonoid and phenolic acid, total content of which were respectively 8.963 mg/g～28.0614 mg/g and 12.3767 mg/g～31.8915 mg/g. Through the studies of antioxidant activities, it indicated that ethanol extracts of different bamboo species all had potent antioxidant activities, which was positively correlated with total flavonoids and phenolic acid. This paper provided a scientific basis for the research of active constituent and the exploitation of bamboo leaves from different species.

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