RESUMEN
Lack of carbon source is the main limiting factor in the denitrification of low C/N ratio wastewater in the constructed wetlands (CWs). Agricultural waste has been considered as a supplementary carbon source but research is still limited. To solve this problem, ferric carbon (Fe-C) + zeolite, Fe-C + gravel, and gravel were used as substrates to build CWs in this experiment, aiming to investigate the effects of different carbon sources (rice straw, corncobs, alkali-heated corncobs) on nitrogen removal performance and microbial community structure in CWs for low C/N wastewater. The results demonstrated that the microbial community and effluent nitrogen concentration of CWs were mainly influenced by the carbon source rather than the substrate. Alkali-heated corncobs significantly enhanced the removal of NO2--N, NH4+-N, NO3-N, and TN. Carbon sources addition increased microbial diversity. Alkali-heated corncobs addition significantly increased the abundance of heterotrophic denitrifying bacteria (Proteobacteria and Bacteroidota). Furthermore, alkali-heated corncobs addition increased the copy number of nirS, nosZ, and nirK genes while greenhouse gas fluxes were lower than common corncobs. In summary, alkali-heated corncobs can be considered as an effective carbon source.
Asunto(s)
Aguas Residuales , Zea mays , Desnitrificación , Humedales , Nitrógeno/análisis , Carbono/química , Eliminación de Residuos Líquidos/métodosRESUMEN
Recent studies have suggested that the anticancer activity of disulfiram (DSF, an FDA-approved alcohol-abuse drug) is Cu-dependent. Low system toxicity and explicit pharmacokinetic characteristics of DSF necessitate safe and effective Cu supplementation in local lesion for further applications. Herein, we presented a new conceptual 'nanosized coordination transport' strategy of Cu(ii) that was realized in porphyrin-based metal-organic frameworks, Sm-TCPP, with strong binding ability to Cu(ii) due to their coordination interactions. Sm-TCPP(Cu) was coated by hyaluronic acid (HA) that termed by Sm-TCPP(Cu)@HA, acting as 'beneficial horse' to target the tumor-localized HA receptor (CD44), thus liberating Cu(ii) ions in cellular overexpressed reductants. The CD44-mediated Cu(ii) accumulation efficiency of Sm-TCPP(Cu)@HA was benchmarked in vitro and vivo against the free TCPP (Cu) via ICP-MS analysis. More importantly, the sensitization effects of Sm-TCPP(Cu)@HA on the anticancer activity of DSF were demonstrated in vivo and in vitro. This study offered a new class of targeted Cu supplements to sensitize DSF for the effective treatment of cancer and established a versatile methodology for constructing a safe and specific delivery of metal ions within living organisms.