Optimum Doses and Forms of Selenium Maintaining Reproductive Health via Regulating Homeostasis of Gut Microbiota and Testicular Redox, Inflammation, Cell Proliferation, and Apoptosis in Roosters.

BACKGROUND: There is a U-shaped relationship between dietary selenium (Se) ingestion and optimal sperm quality. OBJECTIVES: This study aimed to investigate the optimal dietary dose and forms of Se for sperm quality of breeder roosters and the relevant mechanisms. METHODS: In experiment 1, 18-wk-old Jingbai laying breeder roosters were fed a Se-deficient base diet (BD, 0.06 mg Se/kg), or the BD + 0.1, 0.2, 0.3, 0.4, 0.5, or 1.0 mg Se/kg for 9 wk. In experiment 2, the roosters were fed the BD or the BD + sodium selenite (SeNa), seleno-yeast (SeY), or Se-nanoparticles (SeNPs) at 0.2 mg Se/kg for 9 wk. RESULTS: In experiment 1, added dietary 0.2 and 0.3 mg Se/kg led to higher sperm motility and lower sperm mortality than the other groups at weeks 5, 7, and/or 9. Furthermore, added dietary 0.2-0.4 mg Se/kg produced better testicular histology and/or lower testicular 8-hydroxy-deoxyguanosine than the other groups. Moreover, integrated testicular transcriptomic and cecal microbiomic analysis revealed that inflammation, cell proliferation, and apoptosis-related genes and bacteria were dysregulated by Se deficiency or excess. In experiment 2, compared with SeNa, SeNPs slightly increased sperm motility throughout the experiment, whereas SeNPs slightly reduced sperm mortality compared with SeY at week 9. Both SeY and SeNPs decreased malondialdehyde in the serum than those of SeNa, and SeNPs led to higher glutathione peroxidase (GPX) and thioredoxin reductase activities and GPX1 and B-cell lymphoma 2 protein concentrations in the testis compared with SeY and SeNa. CONCLUSIONS: The optimal dietary Se dose for reproductive health of breeder roosters is 0.25-0.35 mg Se/kg, and SeNPs displayed better effects on reproductive health than SeNa and SeY in laying breeder roosters. The optimal doses and forms of Se maintain reproductive health of roosters associated with regulation intestinal microbiota homeostasis and/or testicular redox balance, inflammation, cell proliferation, and apoptosis.

Peroxymonosulfate activation by CuMn-LDH for the degradation of bisphenol A: Effect, mechanism, and pathway.

The remediation of water contaminated with bisphenol A (BPA) has gained significant attention. In this study, a hydrothermal composite activator of Cu3Mn-LDH containing coexisting phases of cupric nitrate (Cu(NO3)2) and manganous nitrate (Mn(NO3)2) was synthesized. Advanced oxidation processes were employed as an effective approach for BPA degradation, utilizing Cu3Mn-LDH as the catalyst to activate peroxymonosulfate (PMS). The synthesis of the Cu3Mn-LDH material was characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). According to the characterization data and screening experiments, Cu3Mn-LDH was selected as the best experimental material. Cu3Mn-LDH exhibits remarkable catalytic ability with PMS, demonstrating good degradation efficiency of BPA under neutral and alkaline conditions. With a PMS dosage of 0.25 g·L-1 and Cu3Mn-LDH dosage of 0.10 g·L-1, 10 mg·L-1 BPA (approximately 17.5 µM) can be completely degraded within 40 min, of which the TOC removal reached 95%. The reactive oxygen species present in the reaction system were analyzed by quenching experiments and EPR. Results showed that sulfate free radicals (SO4•-), hydroxyl free radicals (•OH), superoxide free radicals (•O2-), and nonfree radical mono-oxygen were generated, while mono-oxygen played a key role in degrading BPA. Cu3Mn-LDH exhibits excellent reproducibility, as it can still completely degrade BPA even after four consecutive cycles. The degradation intermediates of BPA were detected by GCMS, and the possible degradation pathways were reasonably predicted. This experiment proposes a nonradical degradation mechanism for BPA and analyzes the degradation pathways. It provides a new perspective for the treatment of organic pollutants in water.

Efficient Adsorption Capacity of MgFe-Layered Double Hydroxide Loaded on Pomelo Peel Biochar for Cd (II) from Aqueous Solutions: Adsorption Behaviour and Mechanism.

A novel pomelo peel biochar/MgFe-layered double hydroxide composite (PPBC/MgFe-LDH) was synthesised using a facile coprecipitation approach and applied to remove cadmium ions (Cd (II)). The adsorption isotherm demonstrated that the Cd (II) adsorption by the PPBC/MgFe-LDH composite fit the Langmuir model well, and the adsorption behaviour was a monolayer chemisorption. The maximum adsorption capacity of Cd (II) was determined to be 448.961 (±12.3) mg·g-1 from the Langmuir model, which was close to the actual experimental adsorption capacity 448.302 (±1.41) mg·g-1. The results also demonstrated that the chemical adsorption controlled the rate of reaction in the Cd (II) adsorption process of PPBC/MgFe-LDH. Piecewise fitting of the intra-particle diffusion model revealed multi-linearity during the adsorption process. Through associative characterization analysis, the adsorption mechanism of Cd (II) of PPBC/MgFe-LDH involved (i) hydroxide formation or carbonate precipitation; (ii) an isomorphic substitution of Fe (III) by Cd (II); (iii) surface complexation of Cd (II) by functional groups (-OH); and (iv) electrostatic attraction. The PPBC/MgFe-LDH composite demonstrated great potential for removing Cd (II) from wastewater, with the advantages of facile synthesis and excellent adsorption capacity.

AP-1 and SP1 trans-activate the expression of hepatic CYP1A1 and CYP2A6 in the bioactivation of AFB1 in chicken.

Dietary exposure to aflatoxin B1 (AFB1) is harmful to the health and performance of domestic animals. The hepatic cytochrome P450s (CYPs), CYP1A1 and CYP2A6, are the primary enzymes responsible for the bioactivation of AFB1 to the highly toxic exo-AFB1-8,9-epoxide (AFBO) in chicks. However, the transcriptional regulation mechanism of these CYP genes in the liver of chicks in AFB1 metabolism remains unknown. Dual-luciferase reporter assay, bioinformatics and site-directed mutation results indicated that specificity protein 1 (SP1) and activator protein-1 (AP-1) motifs were located in the core region -1,063/-948, -606/-541 of the CYP1A1 promoter as well as -636/-595, -503/-462, -147/-1 of the CYP2A6 promoter. Furthermore, overexpression and decoy oligodeoxynucleotide technologies demonstrated that SP1 and AP-1 were pivotal transcriptional activators regulating the promoter activity of CYP1A1 and CYP2A6. Moreover, bioactivation of AFB1 to AFBO could be increased by upregulation of CYP1A1 and CYP2A6 expression, which was trans-activated owing to the upregulalion of AP-1, rather than SP1, stimulated by AFB1-induced reactive oxygen species. Additionally, nano-selenium could reduce ROS, downregulate AP-1 expression and then decrease the expression of CYP1A1 and CYP2A6, thus alleviating the toxicity of AFB1. In conclusion, AP-1 and SP1 played important roles in the transactivation of CYP1A1 and CYP2A6 expression and further bioactivated AFB1 to AFBO in chicken liver, which could provide novel targets for the remediation of aflatoxicosis in chicks.

A review of the degradation of antibiotic contaminants using advanced oxidation processes: modification and application of layered double hydroxides based materials.

In recent years, the treatment of organic pollutants has become a global concern due to the threat to human health posed by emerging contaminants, especially antibiotic contamination. Advanced oxidation processes (AOPs) can solve the organic pollution problem well, which have been identified as a promising solution for the treatment of hard-to-handle organic compounds including antibiotic contaminants. Layered double hydroxides (LDHs) are excellent catalysts because of their flexible tunability, favorable thermal stability, abundant active sites, and facile exchangeability of intercalated anions. This paper conducted a systematic review of LDHs-based materials used for common antibiotic removal by three significant AOP technologies, such as photocatalysis, the Fenton-like processes, and peroxymonosulfate catalysis. The degradation effects studied in various studies were reviewed, and the mechanisms were discussed in detail based on the type of AOPs. Finally, the challenges and the application trends of AOPs that may arise were prospected. The aim of this study is to suggest ways to provide practical guidance for the screening and improvement of LDH materials and the rational selection of AOPs to achieve efficient antibiotic degradation. This could lead to the development of more efficient and environmentally friendly materials and processes for degrading antibiotics, with significant implications for our ecological conservation by addressing water pollution.

Remediation Strategies for Mycotoxins in Animal Feed.

Mycotoxins occur widely in various animal feedstuffs, with more than 500 mycotoxins identified so far [...].

Keratinase improves the growth performance, meat quality and redox status of broiler chickens fed a diet containing feather meal.

The objective of this study was to assess the effects of dietary supplementation of keratinase on the production of broilers fed a diet containing feather meal. A total of 162 1-d-old Cobb 500 male broiler (n = 9 cages/diet with 6 chicks/cage) were randomly allocated to 3 dietary treatments. The broilers were fed a corn-soybean-feather meal based diet (BD), or BD supplemented with keratinase at 100,000 or 200,000 U/kg for 6 weeks. Compared to the control, dietary supplementation with 200,000 U/kg keratinase increased (P < 0.05) body weight gain (3.6-4.3%) and reduced feed conversion ratio (2.4-5.6%) during the various experimental periods, and also improved (P < 0.05) apparent total tract digestibility of ash and calcium by 45.0% and 8.8%, respectively. Meanwhile, dietary supplementation of keratinase at 100,000 U/kg reduced (P < 0.05) the drip loss (29.2%), while 200,000 U/kg keratinase supplementation increased (P < 0.05) the pH value (1.6%) at 45 min and decreased (P < 0.05) the lightness (L* value; 13.6%) and drip loss (22.1%) of pectoral muscle. Moreover, dietary supplementation of keratinase at both levels of 100,000 and 200,000 U/kg increased (P < 0.05) Glutathione peroxidase activity (82.5-87.5%) and decreased the Malondialdehyde concentration (14.5-18.3%) in the pectoral muscle. In conclusion, dietary supplementation of keratinase at 200,000 U/kg can improve the performance, meat quality, apparent total tract digestibility of nutrients, and redox status of broiler chickens fed a diet containing feather meal.

Functionalized silicon nanoparticles from reactive cavitation erosion of silicon wafers.

A new sonochemical process for the top-down production of silicon nanoparticles (<1 nm) with surface functional groups is described. The procedure involves a combination of acoustic cavitation erosion of a single-crystalline silicon surface coupled with simultaneous reaction with a reactive organic compound such as 1-hexyne. The sonochemical formation of the photoluminescent silicon nanoparticles by reactive cavitation erosion can be easily up-scaled.

Cytotoxicity of surface-functionalized silicon and germanium nanoparticles: the dominant role of surface charges.

Although it is frequently hypothesized that surface (like surface charge) and physical characteristics (like particle size) play important roles in cellular interactions of nanoparticles (NPs), a systematic study probing this issue is missing. Hence, a comparative cytotoxicity study, quantifying nine different cellular endpoints, was performed with a broad series of monodisperse, well characterized silicon (Si) and germanium (Ge) NPs with various surface functionalizations. Human colonic adenocarcinoma Caco-2 and rat alveolar macrophage NR8383 cells were used to clarify the toxicity of this series of NPs. The surface coatings on the NPs appeared to dominate the cytotoxicity: the cationic NPs exhibited cytotoxicity, whereas the carboxylic acid-terminated and hydrophilic PEG- or dextran-terminated NPs did not. Within the cationic Si NPs, smaller Si NPs were more toxic than bigger ones. Manganese-doped (1% Mn) Si NPs did not show any added toxicity, which favors their further development for bioimaging. Iron-doped (1% Fe) Si NPs showed some added toxicity, which may be due to the leaching of Fe(3+) ions from the core. A silica coating seemed to impart toxicity, in line with the reported toxicity of silica. Intracellular mitochondria seem to be the target for the toxic NPs since a dose-, surface charge- and size-dependent imbalance of the mitochondrial membrane potential was observed. Such an imbalance led to a series of other cellular events for cationic NPs, like decreased mitochondrial membrane potential (ΔΨm) and ATP production, induction of ROS generation, increased cytoplasmic Ca(2+) content, production of TNF-α and enhanced caspase-3 activity. Taken together, the results explain the toxicity of Si NPs/Ge NPs largely by their surface characteristics, provide insight into the mode of action underlying the observed cytotoxicity, and give directions on synthesizing biocompatible Si and Ge NPs, as this is crucial for bioimaging and other applications in for example the field of medicine.