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In this study, the residue levels of chiral pesticide hexaconazole during kiwifruit juice processing (peeling, homogenization, and sterilization) were investigated by using high-performance liquid chromatography (HPLC), and the dietary risk during these processes was also assessed. Hexaconazole was applied at dosages of 173.33 and 346.66 mg/L (recommended and double recommended dosage) in kiwifruit. In the peeling process, 87.7% to 89.2% of the residues were decreased after peeling. Levels of hexaconazole residues in homogenization and sterilization processes further increased from 0.49% to 24.3% and from 0.2% to 3.0%, respectively. Processing factors (PFs) for (+)- and (−)-hexaconazole after peeling, homogenization, and sterilization were 0.12, 0.88, 0.99 for low-dose treatment and 0.12, 0.87, 0.99 for high-dose treatment, respectively. The enantioselectivity of hexaconazole during these procedures was evaluated by enantiomeric fractions (EFs) values, which were around 0.5 throughout all the procedures, indicating that hexaconazole enantiomers had similar dissipation behaviors during kiwifruit juice processing. The RQc of hexaconazole in pre-peeling samples was significantly greater than 100% under two dosages, while the peeling process can notably decrease the values to an acceptable level. The results of this study could provide guidance for agriculture applications and kiwi commodity production to decrease the risk of hexaconazole residue. [ABSTRACT FROM AUTHOR]

A novel magnetic hollow bimetallic zinc/cobalt-based zeolitic imidazolate framework (MHB-Zn/Co-ZIF-8) was prepared via a microwave-assisted chemical etching in methanol. The structure, morphology, and specific surface area were characterized by X-ray diffraction and FTIR spectroscopy, scanning and transmission electron microscopy, and N2 adsorption. The hollow nanostructures with high internal specific surface area, abundant active sites, and reduced aggregation of nanoparticles endow the hollow zeolitic imidazolate framework (ZIF) nanoparticle with high chemical stability, desirable durability, and excellent adsorption abilities. The MHB-Zn/Co-ZIF-8 nanoparticle was used as an effective sorbent for magnetic solid-phase extraction (MSPE) of trace aflatoxins B1, B2, G1, and G2 from fruit juice and fruit samples. The main parameters affecting the efficiency of MSPE procedures were investigated and optimized. The results show that, under optimized conditions, enrichment factors ranging from 67- to 355-fold are obtained for the target analytes. The method is linear in the range 1.0 to 100.0 ng mL−1 with correlation coefficients (R2) from 0.9960 to 0.9992. The limits of detection of four aflatoxins are in the range 0.18 to 1.50 ng mL−1 and the average recoveries range from 75.1 to 102.4%, with relative standard deviations (RSDs) less than 13.6%. This work presents the excellent extraction performance of aflatoxins B1, B2, G1, and G2 on MHB-Zn/Co-ZIF-8. In addition, the applicability of the MSPE coupling with ultrahigh-performance liquid chromatography-ion trap tandem mass spectrometry (UHPLC-IT-MSn) for trace analysis in complex matrices is shown. [ABSTRACT FROM AUTHOR]

In this study, the profile of etoxazole in whole citrus, peel and pulp samples collected from Chongqing, Guangdong and Anhui provinces was monitored and their dietary risk to human had also been assessed. The final residual levels and distributions of etoxazole in citrus samples were detected by using an ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). The results showed that final concentrations of etoxazole in whole citrus, peel, and pulp were ranged at 0.012–0.174, 0.010–0.637, and 0.010–0.011 mg kg−1, respectively. The assessment of dietary risk suggested that chronic dietary risk of etoxazole in whole fruit and peel were 0.010–0.197% and 0.035–0.951%, respectively. Our findings indicated that the chronic risk of daily consumption of citrus fruit is acceptable at recommended dosage. • The profile of etoxazole in whole citrus, peel and pulp samples was monitored. • The dietary risk of etoxazole in citrus samples to human had been assessed. • Etoxazole residue distributions were peel > whole citrus > pulp. • The chronic risk of daily consumption of citrus is acceptable at recommended dosage. [ABSTRACT FROM AUTHOR]

Aim: To investigate the mechanism of Lactobacillus rhamnosus GG (LGG)‐secreted protein, P75, on the regulation of the expression of serotonin transporter (SERT) through the epidermal growth factor receptor (EGFR) and nuclear factor‐κB (NF‐κB) pathway. Methods: Caco‐2 cells were stimulated with LGG supernatant (LGG‐super), protein P75, AG1478, and TNF‐α. A rat model of post‐infectious irritable bowel syndrome (PI‐IBS) was constructed and treated with phosphate‐buffered saline and LGG‐super for 4 weeks. The levels of SERT, p‐EGFR, EGFR, p‐NF‐κB, NF‐κB, p‐IκB‐α, and IκB‐α were detected by quantitative real‐time polymerase chain reaction, Western blot, immunofluorescence, and immunochemistry. Luciferase assay was used to verify the link between NF‐κB and SERT promoter. Results: LGG‐super and P75 upregulated the expression levels of SERT and p‐EGFR and decreased the expression levels of p‐IκB‐α and p‐NF‐κB. Dual luciferase assay result suggested that NF‐κB inhibited the activity of SERT promoter. In the animal experiments, 5‐HT concentration increased in the PI‐IBS Model group but decreased in the Model +LGG‐super group compared with the control. On the contrary, the expression of SERT protein was downregulated in the PI‐IBS Model group and improved in the Model +LGG‐super group. The expression of p‐EGFR was reduced and p‐NF‐κB was enhanced in the PI‐IBS Model group, whereas the expression of p‐EGFR and p‐NF‐κB was the opposite in the Model +LGG‐super group. Conclusion: LGG supernatant and its secreted protein, P75, upregulate the expression of SERT by activating EGFR and inhibiting the NF‐κB pathway. [ABSTRACT FROM AUTHOR]

The toxicity effects of chiral pesticides on living organisms have attracted an increasing public attention. This study aims to investigate the toxicity effect and mechanism of hexaconazole (HEX) to human breast cancer cell (MCF-7) at enantiomer levels. HEX exposure obviously inhibited cells activities in a dose-dependent manner. Under the conditions of VIP >1 and p < 0.05, a total of 255 and 177 differential metabolites (DMs), 17 and 15 amino acid- and lipid-related metabolic pathways were disturbed after (+)-HEX and (−)-HEX exposure, respectively. HEX exposure may affect cell membrane function, signal transduction, and cell differentiation. We further investigated the mechanism of enantioselective differences by using molecular docking which showed that CYP17A1 was the main enzyme that leading to endocrine disrupting effects with the binding energy of −6.30 and −6.08 kcal/mol compared to CYP19A1 enzyme which were −5.81 and −5.93 kcal/mol for (+)-HEX and (−)-HEX, respectively. The docking results explained the reasons why (+)-HEX achieved higher cytotoxicity and induced more seriously metabolic profiles than its antipode. These findings could provide a new insight to understand the enantioselective cytotoxicity effect and mechanism of HEX and will be conducive to assessing its risk to human health at enantiomer levels. [Display omitted] • Enantioselective toxicity effect to MCF-7 cells by hexaconazole had been observed. • Hexaconazole exposure significantly affect the metabolic profiles of MCF-7. • Hexaconazole mainly affect lipid- and amino acid-related metabolites and pathways. • (+)-hexaconazole achieved higher cytotoxicity effect to MCF-7 cells than its antipode. [ABSTRACT FROM AUTHOR]

In the karst areas of southwest China, soil fluoride levels are higher than in China (478 mg kg−1) and world (200 mg kg−1). High levels of F in the environment might pose a health risk to humans. The comprehensive exposure risk must be studied in this area. Herein, samples of crops and soil were collected from Bijie City, a typical karst area in southwest China, to investigate the pollution level and evaluate the comprehensive F exposure risk. The single-factor index (P Fw) and the geological accumulation index (I geo) were used. The hazard index (HI) was applied to assess exposure risk from multiple exposure routes. The results revealed that there is considerable F contamination in soil and crops in the study area. Average soil total fluorine (Ft) was 1139.13 mg kg−1, and soil water soluble F (Fw) was 3.792 mg kg−1. In corn, rice, wheat, and potatoes, F contents were 1.167–9.585, 1.222–6.698, 1.587–9.976, and 1.797–9.143 mg kg−1, respectively. The mean values of HI were 4.45 and 2.42 for children and adults, respectively, > 1, showing potential health risk exists. Youngsters are at a greater exposure risk than adults. From the results of contribution ratios of different exposure routes for health risk, the major exposure risk was determined to be from soil exposure. Based on this, we suggest that risk managers mainly strive to control the soil fluoride level and implement the risk education and communication. [Display omitted] • Serious soil F contamination exists in the Bijie area. • Comprehensive health risk assessment of F conducted for local residents. • Children are more prone to F exposure than adults. • Major F exposure risk is from soil. [ABSTRACT FROM AUTHOR]

Abstract: Resveratrol (Res) displays potent anti-oxidant activity and is a selective estrogen receptor modulator. The aim of the present study is to investigate whether Res consumption protects ovariectomized (OVX) rats chronically treated with d-galactose (d-gal) from developing memory decline and whether Res administration decreases pathological changes in the endometrium and lumen of the uterus compared with estradiol replacement therapy. Rats were divided into 6 groups: 1) Sham control group; 2) OVX+ d-gal 100mg/kg group (OVX+ d-gal); 3–5) OVX, d-gal and Res 20, 40, 80mg/kg treated groups; and 6) OVX, d-gal and estradiol valerate 0.8mg/kg treated group (ET). Twelve weeks later, in a Morris water maze test, the OVX+ d-gal rats exhibited a significant memory impairment compared with the Sham control rats, which was accompanied by decreased total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) activities and an increased thiobarbituric acid reactive substances (TBARS) level in the serum. In addition, the TBARS and protein carbonylation levels increased in the hippocampus. The beneficial roles of the 40 and 80mg/kg Res treatments were manifested in the prevention of memory decline and markedly decreased oxidant stress indices. The disruption of the cristae in the mitochondria and the irregular nuclei and condensed chromatin in the pyramidal cells of the hippocampal CA1 region were also reduced after Res treatment. Furthermore, edema in the endometrium and lymphocyte infiltration was avoided in all three of the Res-treated groups compared with the ET group. These results suggest that Res is useful not only in protecting OVX+ d-gal rats from developing memory decline by increasing the anti-oxidation but also in avoiding the effects on the uterus. [Copyright &y& Elsevier]

A magnetic graphene-like molybdenum disulfide nanocomposite was prepared by liquid-phase exfoliation and hydrothermal synthesis. The morphology, structure, and magnetic behavior of the nanocomposite were characterized by X-ray diffraction, FTIR spectroscopy, thermogravimetric analysis, vibrating sample magnetometry, scanning electron microscopy and transmission electron microscopy. The nanocomposite was employed as a sorbent for magnetic solid-phase extraction (MSPE) of eight triazine and ten sulfonylurea herbicides from environmental water and corn samples. Specifically, this was studied with cyanazine, simetryn, atrazine, methoprotryne, ametryn, prometryn, terbutryn, dipropetryn, metsulfuron-methyl, sulfometuron-methyl, amidosulfuron, rimsulfuron, nicosulfuron, bensulfuron-methyl, halosulfuron-methyl, pyrazosulfuron-ethyl, chlorimuron-ethyl, and cyclosulfamuron. The parameters affecting extraction efficiency (sorbent amount, pH value of the sample, extraction and elution conditions) were studied and optimized. Following MSPE, the multi-residue herbicides were quantified by ultra-high performance liquid chromatography combined with ion trap mass spectrometry and electrospray ionization. The limits of detection range between 20 and 170 ng·L−1. The extraction recoveries of eighteen herbicides from corn samples were in the range between of 64.7% and 103.1%, with RSDs of <17.6%. [ABSTRACT FROM AUTHOR]