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Abstract In this study, Zeolite X was prepared by hydrothermal method, and the amidoxime group was loaded on the zeolite X to prepare amidoxime-modified zeolite X. The effective removal of ruthenium by amidoxime-modified zeolite X in simulated wastewater was investigated. The raw and modified zeolite X were characterized systematically using the BET method, the SEM, the FTIR, the XRD and the XPS to understand the physicochemical changes of the materials, and its sensitivity to Ru3+ adsorption. Batch adsorption experiments were carried out to investigate the effects of adsorbent dose, contact time, solution pH, different initial Ru3+ concentrations, temperature and the effect of competitive ions on Ru3+ adsorption. The modified zeolite X exhibited fast removal performance reaching equilibrium within 30 min at the pH of 3, and the maximum adsorption capacity was found to be 175.4 mg/g. The XRD patterns demonstrated that the modified adsorbent still has the characteristic peak of zeolite NaX, and from the SEM, it can be seen that the modified adsorbent shown the same regular octahedral crystal structure as the zeolite X. In addition, the characterization result of FTIR and XPS indicated the amidoxime group was successfully loaded onto zeolite X. Kinetic parameters were fitted by the pseudo-second order model (R2 = 0.9999), and the adsorption process by the modified zeolite X was chemical adsorption. The adsorption isotherms data of modified zeolite X were well-fitted to the Langmuir (R2 = 0.9834).In the competitive ions effect, the modified zeolite X effectively captured the Ru3+ ion in the presence of Na+ and K+. Therefore, the amidoxime-modified zeolite X could be effectively used as a potential adsorbent for Ru3+ adsorption from wastewater. Highlights • Amidoxime-modified zeolite X (AO-ZX) was synthesized successfully. • AO-ZX was useful in the removal of ruthenium (III) ions from wastewater. • Maximum adsorption capacity based on Langmuir isotherm was 175.4 mg/g. • AO-ZX exhibited fast removal performance reaching equilibrium within 30 min. [ABSTRACT FROM AUTHOR]

Ligupurpuroside A is one of the major glycoside in Ku-Din-Cha, a type of Chinese functional tea. In order to better understand its digestion and metabolism in humans, the interaction between Ligupurpuroside A and pepsin has been investigated by fluorescence spectra, UV–vis absorption spectra and synchronous fluorescence spectra along with molecular docking method. The fluorescence experiments indicate that Ligupurpuroside A can effectively quench the intrinsic fluorescence of pepsin through a combined quenching way at the low concentration of Ligupurpuroside A, and a static quenching procedure at the high concentration. The binding constant, binding sites of Ligupurpuroside A with pepsin have been calculated. The thermodynamic analysis suggests that non-covalent reactions, including electrostatic force, hydrophobic interaction and hydrogen bond are the main forces stabilizing the complex. According to the Förster’s non-radiation energy transfer theory, the binding distance between pepsin and Ligupurpuroside A was calculated to be 3.15 nm, which implies that energy transfer occurs between pepsin and Ligupurpuroside A. Conformation change of pepsin was observed from UV–vis absorption spectra and synchronous fluorescence spectra under experimental conditions. In addition, all these experimental results have been validated by the protein-ligand docking studies which show that Ligupurpuroside A is located in the cleft between the domains of pepsin. [ABSTRACT FROM AUTHOR]

[Display omitted] • GmoDetector could detect more than 251 commercialized GMOs and their hybrid crosses. • GmoDetector covered 64 commonly used transgenic elements and their possible combinations, which can identify both authorized and unauthorized GMOs. • GmoDetector can identify and remove the contamination of donor (micro)organisms of transgenic elements. • The sensitivity of GmoDetector has achieved the threshold of GMO labeling required by worldwide. The rapid increase of genetically modified organisms (GMOs) entering the food and feed markets, and the contamination of donor (micro)organisms of transgenic elements make it more challenging for the existing GMO detection. In this study, we developed a high-throughput and contamination-removal GMO detection approach named as GmoDetector. GmoDetector targeted 64 common transgenic elements and 76 GMO-specific events collected from 251 singular GM events, and combined with next generation sequencing (NGS) and target enrichment technology to detect various GMOs. As a result, GmoDetector was able to exclude the donor (micro)organism contamination, and detect the authorized and unauthorized GMOs (UGMOs) in any forms of food or feed, such as processed or unprocessed. The sensitivity of GmoDetector is as low as 0.1% (GMO content), which has met the GMO labeling threshold for all countries. Therefore, GmoDetector is a robust tool for accurate and efficient detection of the authorized and UGMOs. [ABSTRACT FROM AUTHOR]