RESUMEN
The design of high-performance porous adsorbents for phosphorus removal is a persistently hot topic to maintain a sustainable aquatic ecosystem. In the present study, a self-templating strategy using LaFe cyanometallates (CMs) as precursors was adopted to prepare porous LaFe bimetal oxides with optimizable structure and composition for phosphate adsorption. The results showed that a high supplied LaIII/FeII ratio enabled an adequate coordination polymerization in the preparation of LaFe CM precursor and led to a striking three-dimensional (3D) structure of "twin lotus flower" with high coordinated water content, which resulted in a 3D flower-like LaFe oxide with high surface area and high porosity (mainly in mesopore). The LaFe oxide of LaFe15T possessing the optimal La/Fe ratio (1.5: 1) exhibited the most superior performance of phosphate adsorption, where La was confirmed to be the main active site for phosphate capture via ligand exchange mechanism. The batch and column tests of phosphate adsorption showed that the 3D flower-like LaFe oxides are effective adsorbents for phosphate removal. Therefore, the structure optimization in the template preparation stage is an effective strategy to design porous LaFe bimetal oxides as high-performance phosphorus removal materials.
Asunto(s)
Óxidos , Fósforo , Óxidos/química , Dominio Catalítico , Ecosistema , Adsorción , Fosfatos/químicaRESUMEN
Background Fatty acid synthase (FAS) is a key enzyme of de novo lipogenesis (DNL), which has been cloned from several species: Gallus gallus, Mus musculus, Homo sapiens, but not from Anas platyrhynchos. The current study was conducted to obtain the full-length coding sequence of Peking duck FAS and investigate its expression during adipocyte differentiation. Results We have isolated a 7654 bp fragment from Peking duck adipocytes that corresponds to the FAS gene. The cloned fragment contains an open reading frame of 7545 bp, encodes a 2515 amino acid protein, and displays high nucleotide and amino acid homology to avian FAS orthologs. Twelve hour treatment of oleic acid significantly up-regulated the expression of FAS in duck preadipocytes (P < 0.05). However, 1000 µM treatment of oleic acid exhibited lipotoxic effect on cell viability (P < 0.05). In addition, during the first 24 h of duck adipocyte differentiation FAS was induced; however, after 24 h its expression level declined (P < 0.05). Conclusion We have successfully cloned and characterized Peking duck FAS. FAS was induced during adipocyte differentiation and by oleic acid treatment. These findings suggest that Peking duck FAS plays a similar role to mammalian FAS during adipocyte differentiation.