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Polybrominated diphenyl ethers (PBDEs) are one class of brominated flame retardants (BFRs). Although studies have reported the occurrence of PBDEs in freshwater fish species from several locations, to our best knowledge, there was no comprehensive data on PBDEs in foods of animal origin, such as pork, egg, and milk samples from interior areas of China, where pork and eggs are the major constituents of diet. The levels of PBDEs (BDE-28, 47, 99, 100, 153, 154, and 183) were determined in samples of animal-derived foods widely consumed by the population of Hubei in east-central China and the middle reaches of the Yangtze River. Two hundred six samples of animal-derived foods were randomly acquired in 17 sites of Hubei in 2010. The highest medium concentration of ∑PBDEs was found in chicken eggs (0.191 ng/g wet weight (ww)), followed by duck eggs (0.176 ng/g ww), pork (0.050 ng/g ww), carps (0.047 ng/g ww), and cow milk (0.013 ng/g ww). The estimated dietary intake of ΣPBDEs for a standard adult of 60 kg body weight based on medium and 95th percentile concentrations with consumption of animal-derived foods in Hubei province were 157.5 and 1960.3 pg/kg body weight/day, respectively. Chicken eggs (65.9 %) and pork (23.4 %) were the largest contributors to dietary intake of ∑PBDEs through animal-derived foods. The same PBDE sources were exposed in Hubei province via principal component analysis (PCA), and the particular congener profile in samples of animal-derived foods revealed the possible exposure history of octa-BDEs and penta-BDEs in the local region. The large margins of exposure (MOE) calculated following the European Food Safety Authority (EFSA) approach for three important congeners, BDE-47, BDE-99, and BDE-153, indicated that the estimated dietary exposures were unlikely to be a significant health concern to in Hubei. [ABSTRACT FROM AUTHOR]

Mung bean coat has long been known for its wide-ranging health benefits, including antibacterial, anti-inflammatory, and immune-modulatory properties. For many years in China, mung beans have been employed in the therapeutic management of inflammation induced by pathogenic bacteria infection, yet the precise underlying protective mechanisms remain to be comprehensively elucidated. Given the growing concern over antibiotic resistance, there is a necessity to explore new anti-infective agents. Here, the anti-infective properties of Mung bean coat extract (MBCE) were investigated using a model of Pseudomonas aeruginosa-infected nematodes. The protective effects of MBCE on Pseudomonas aeruginosa (PA14) infected nematodes were assessed by lifespan assay, reactive oxygen species (ROS) levels, transcriptomics, and Quantitative real-time PCR (qRT-PCR). MBCE significantly improved the survival rates and reduced ROS levels in infected worms. Transcriptomic profiling disclosed predominant KEGG pathway enrichments in immune responses, energy metabolism processes such as oxidative phosphorylation and the tricarboxylic acid cycle, alongside aging-related neurodegenerative diseases and longevity regulatory pathways like PI3K-AKT, MAPK, mTOR, and FOXO. qRT-PCR validation showed that MBCE upregulated antimicrobial peptides (spp-3 , lys-1 , lys-7 , abf-2 , cnc-2 , nlp-33 , clec-85), gram-negative responses (irg-3 , src-2 , grd-3, col-179), and mitochondrial function (mev-1) gene expressions, while downregulated insulin signaling-related (age-1 , akt-1 , akt-2, daf-15) gene expressions. Mutant strains lifespan analysis indicated that the nsy-1 , sek-1 , pmk-1 , daf-2 , aak-2 , sir-2.1 , and skn-1 were necessary for lifespan extension mediated by MBCE under PA14 infection, but not clk-1 , isp-1 , mev-1 , or daf-16. Collectively, our findings suggested that MBCE increased the survival rates of PA14-infected worms by activating downstream antimicrobial and antioxidant gene expressions through modulation of MAPK, daf-2 , aak-2 , sir-2.1 , and skn-1 pathways. The research underscored the potential of natural plant compounds to strengthen the body's defenses against infections, potentially mitigating harmful ROS levels and improving survival. Additionally, these findings elucidated the mechanisms by which these plant-derived compounds enhance the immune system, implying their potential utility as dietary supplements or as an alternative to conventional antibiotics. [Display omitted] • MBCE extended lifespan in a nematodes model infected with Pseudomonas aeruginosa 14. • MBCE upregulated the expressions of antimicrobial peptides and antioxidant genes of Pseudomonas aeruginosa 14-infected nematodes in transcriptome sequencing. • nsy-1 , sek-1 , pmk-1 , daf-2 , aak-2 , sir-2.1 , and skn-1 were necessary for MBCE's anti-infection. [ABSTRACT FROM AUTHOR]

A simple and sensitive method combining solid-phase extraction (SPE) and high-performance liquid chromatography-ultraviolet detection (HPLC-UV) was developed for the determination of benzo[ a ]pyrene (BaP) in fish. Loofah sponge (LS) was carbonized and used as an SPE adsorbent. Carbonization decreased the polarity of LS and enhanced its aromaticity. Carbonized loofah sponge (CLS) could capture BaP better through π-π interaction. The carbonization temperature and the SPE conditions were optimized. The linear range of the developed method was within 10-1000 ng g -1 with a satisfactory correlation coefficient ( R 2 ) of 0.9999. The limit of detection (LOD) was 2.0 ng g -1 , which was below the maximum residue limit (5 μg kg -1 ) in meat set by the European Union. The method showed good intra-day and inter-day precision with relative standard deviations (RSDs) ranging from 0.4% to 1.7%. Finally, the developed method was applied to the determination of BaP in fish samples. This method is low-cost and environmentally friendly with natural and renewable LS as raw material and it provides an alternative approach for the efficient and simple determination of BaP in aquatic products.

An improved QuEChERS (quick, easy, cheap, effective, rugged, safe) method, combined with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), was used to determine bongkrekic acid (BA) in tremella and auricularia auricular. BA is a fat-soluble, fatal bacterial toxin produced by the aerobic gram-negative bacteria Burkholderia gladioli pathovar cocovenenans. Tremella and auricularia auricular, which have rich nutritional values, are traditional edible fungi in China that are very popular among Chinese consumers. However, tremella and auricularia auricular are easily contaminated by BA during storage and foaming, and this poses a great threat to food safety and human health. Therefore, establishing a rapid and efficient analysis method for detecting BA in tremella and auricularia auricular is of considerable significance. However, the BA concentration in the actual sample is very low, and the matrices of tremella fuciformis and auricularia auricular are very complex. Thus, it is necessary to employ appropriate sample pretreatment technology to extract and purify BA from tremella and auricularia auricular samples prior to instrumental analysis. In this study, the QuEChERS method, combined with UHPLC-MS/MS, was used to detect BA in tremella and auricularia auricular. The key parameters, such as extraction solvent, extraction method, and adsorbent used for cleanup, were optimized to obtain high extraction efficiency. The content of acetic acid in the extraction solution strongly influenced the extraction efficiency of BA, and acetonitrile with 5%(v/v) acetic acid was determined to be the optimum extraction solvent. After salting out, the acetonitrile extract was purified by dispersive solid phase extraction using 200 mg C18 as a cleanup adsorbent. The sample was then separated on a Waters HSS T3 column (100 mm×2.1 mm, 1.8 μm), using a water solution containing 0.01% (v/v) formic acid and 0.05% (v/v) ammonia and methanol as mobile phases. MS analysis was performed using an electrospray ionization source in the negative and multiple reaction monitoring (MRM) modes. Under the optimized conditions, the matrix effects of UHPLC-MS/MS in tremella and auricularia auricular were -6.3% and -11.5%, respectively; this indicated that the method had a significant purification effect, and the sample matrix did not affect the MS detection of BA. Further study showed that in the concentration range of 1-200 μg/L, the square of the regression coefficient of the linear equation ( R 2 ) was greater than 0.999. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.15 μg/kg and 0.5 μg/kg, respectively. The average recoveries in samples spiked with 0.5, 10, and 50 μg/kg BA in tremella ranged from 92.4% to 102.6%, and the intra-day and inter-day relative standard deviations (RSDs) were 4.3%-4.9% and 3.2%-3.5%, respectively. For auricularia auricular, the average recoveries ranged from 89.6% to 102.3%, and the intra-day and inter-day RSDs were 2.4%-9.5% and 3.6%-4.1%, respectively. These results indicate that the proposed method has satisfactory sensitivity, accuracy, and precision. Finally, the method showed good performance when applied to the analysis of real samples. Compared with other reported methods, the LOD and LOQ of our proposed method were lower, with satisfactory recovery and precision. Taken together, this study provides an effective detection technology for the monitoring and risk control of BA in tremella and auricularia auricular.

Mn 2+ -doped amino lead halide molecular clusters (MCs) are synthesized using amine (e.g., n -octylamine, or butylamine) as passivating ligand and MnX 2 (X = Cl or Br) as the Mn 2+ doping source at room temperature. Their optical properties are investigated with UV-visible absorption, photoluminescence (PL), and PL excitation spectroscopy. The Mn 2+ precursor plays a vital role in the synthesis of Mn 2+ -doped MCs. MnCl 2 seems to facilitate the incorporation of Mn. The MnCl 2 doping causes electronic absorption blue shift and leads to a spin-forbidden 4 T 1 → 6 A 1 Mn d-electron emission. With the help of time-resolved PL, Fourier transform infrared, and electron paramagnetic resonance results, a model is proposed to explain the formation mechanism. We suggest that Mn 2+ doping replaces Pb 2+ is assisted by Cl - ions that replace Br - ions. This study demonstrates the possibility of doping MCs and has important implications in gaining new fundamental insight into the growth mechanisms of perovskite nanostructures.

A "mixed ligand" octyl-carboxylic co-bonded silica (OCS) packing was prepared by the method of "click chemistry". The resulting OCS packing was characterized by elemental analysis (EI) and Fourier transform infrared spectroscopy (FT-IR) to prove the successful immobilization of octyl and carboxylic groups on the surface of silica gel. Then the mixed-mode reversed-phase/weak-cationic-exchange (RP/WCX) retention mechanism of the OCS packing was quantitatively probed by studying the retention factors of a homologous series of three cationic surfactants on the mixed-mode stationary phase column as a function of the ammonium concentration in the eluent or the number of methylene groups in the solute. The one-site and two-site mixed-mode retention models of the three cationic surfactants on the OCS phases were studied by investigating the logarithm and reciprocal relationships of retention factors and salt concentrations, demonstrating that the two-site model was more suitable for the description of individual RP or WCX contribution to total retention was obtained according to the mathematical equations of two-site retention mechanism, which can provide some valuable guidance for the separation of real samples. This study developed the qualitative model of retention mechanism of the mixed-mode OCS packing, and a series of standard basic mixtures were well separated on the OCS packing, demonstrating the great application potential of OCS packing for the separation of various basic compounds.

A simple and efficient method has been proposed for the preparation of octyl-sulfonic co-bonded silica (OSS) packing by the method of "mixed ligand". The resulting OSS packing was characterized by elemental analysis and ion-exchange capacity to prove the successful immobilization of octyl and sulfonic groups on the surface of silica gel. Then the retention mechanism of several basic analytes on the developed OSS phases was evaluated under the conditions of reversed-phase liquid chromatography (RPLC) mobile phase. The results indicated that the OSS stationary phases demonstrated a mixed-mode reversed-phase/strong-cationic-exchange (RP/SCX) retention mechanism and ion-exchange interaction maybe dominate the retention of the basic analytes. By changing the salt concentration of mobile phase, the one-site and two-site mixed-mode retention models of the several basic analytes on the OSS phases were obtained by investigating the logarithm and reciprocal relationships of retention factor and salt concentration. On the basis of the linear fitting of the two mathematical equations of the retention models, the experimental results demonstrated that the two-site model was more suitable for the description of the retention mechanism of the basic analytes on the OSS phases. Furthermore, the individual RP or SCX contribution to total retention was obtained according to the mathematical equations of the two-site retention mechanism, which can provide some valuable guidance for the separation of complex samples.