Chunsheng Xie,Shoulian Wei,Dan Chen,Wenying Lan,Zijun Yan,Zhenxing Wang
In this work, a magnetic ion imprinted polymer (MIIP) with specific recognition capability toward cadmium was prepared by a sol–gel method using waste beer yeast, which is a macromolecule biomass, as a functional monomer. The obtained Cd(II)-MIIP was characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and adsorption experiments. Then, a MIIP adsorbent based magnetic solid phase extraction (MSPE)-graphite furnace atomic absorption (GFAA) method was established to analyze the cadmium content in food and environmental samples. The maximum cadmium adsorption capacities by the MIIP and magnetic non-imprinted polymer (MNIP) were 62.74 and 32.38 mg g−1, respectively. The absorption by the MIIP was fitted using a pseudo-second-order kinetic model. The Cd(II)-MIIP demonstrated superior absorption capability for selective removal cadmium. The recovery rate of the MIIP was 90.7% after four adsorption–desorption cycles. The calculated Cd(II) detection limit (S/N = 3) was 0.18 μg L−1 with the relative standard deviation (RSD) equal to ∼3.5% for 10 μg L−1 of Cd(II) standard solution. Our proposed method was successfully used in detecting Cd(II) in aqueous samples. The results obtained in this work suggest that the Cd(II)-MIIPs might be promising adsorbents to remove harmful cadmium ions from aqueous samples.
Zixuan Hu,Chunfeng Liu,Chengtuo Niu,Jinjing Wang,Feiyun Zheng,Qi Li
Brewer's spent grain (BSG) and brewer's spent yeast (BSY) are two major brewing by-products, which are low-cost raw materials with high yields and nutritional value. In this study, the antioxidant peptides from brewing by-products were separated, purified and identified by UF, GFC or HIC, semi-preparative RP-HPLC, and nano-HPLC-MS/MS. Thereafter, in silico analysis was applied to predict the bioactivity, toxicity, and bioavailability of the identified peptides, and a total of 23 potential novel peptides with antioxidant activity and bioavailability were excavated. Furthermore, molecular docking results revealed the potential antioxidant peptides had stable binding ability to Keap1, and Tyr334, Arg380, Arg415, Arg483, and Tyr525 residues contributed enormously to docking, all of which were located in the binding sites of Keap1-Nrf2 interaction. Peptides with the lowest binding energy (i.e. AGRLPW, DRLW, KPW, PLWWRHPR, RVWNPFR, and ANLPWLGK) were further synthesized and validated in vitro and at the cellular level to be bioactive. Western blot results showed that KPW, RVWNPFR, and ANLPWLGK could protect HaCaT cells from H 2 O 2 -induced oxidative damage by activating Keap1-Nrf2 pathway. These findings provided insights into the high value-added utilization of brewing by-products.
危险品化学品经营许可证（带存储）