The primary aim of this study was to investigate the alterations in the microbial community of KK-Ay mice following antibiotic treatment. A comparative analysis of the gut microbiota was conducted between KK-Ay mice treated with antibiotics and those without treatment. The microbial community dynamics in antibiotic-treated KK-Ay mice were meticulously assessed over an eight-week period using 16S rDNA sequencing analysis. Simultaneously, dynamic renal function measurements were performed. The results demonstrated a marked decrease in bacterial DNA abundance following antibiotic intervention, coupled with a substantial reduction in bacterial diversity and a profound alteration in microbial composition. These observed microbiota changes persisted in the KK-Ay mice throughout the eight-week post-antibiotic treatment period. Particularly noteworthy was the reemergence of bacterial populations after two weeks or more, resulting in a microbiota composition resembling that of untreated KK-Ay mice. This transition was characterized by a significant increase in the abundance of clostridia at the class level, Lachnospirales and Oscillospirales at the order level, and Lachnospiraceae, Oscillospiraceae, and Ruminococcaceae at the family level. Concurrently, there was a notable decrease in Clostridia_UCG-014. The observed alterations in the gut microbiota of antibiotic-treated KK-Ay mice suggest a dynamic response to antibiotic intervention and subsequent restoration towards the original untreated state.
- MeSH
- antibakteriální látky * farmakologie aplikace a dávkování MeSH
- Bacteria * klasifikace genetika účinky léků izolace a purifikace MeSH
- biodiverzita MeSH
- DNA bakterií genetika MeSH
- feces mikrobiologie MeSH
- fylogeneze MeSH
- myši MeSH
- ribozomální DNA genetika MeSH
- RNA ribozomální 16S * genetika MeSH
- sekvenční analýza DNA MeSH
- střevní mikroflóra * účinky léků MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Layered double hydroxide (LDH) is one of the key host phases of Cr(VI) in the natural environment and chromite ore processing residue (COPR), causing serious pollution by Cr(VI). Therefore, efficient extraction or immobilization of the incorporated Cr(VI) in LDH is urgently needed. In this work, simultaneous separation and immobilization of Cr(VI) in LDH by using MgCl2·6H2O under thermal treatment is innovatively proposed. Cr was volatilized as CrCl3 and was immobilized as MgCr2O4 accounted for 62.2% and 37.8%, respectively, under the optimal condition (the mole ratio of Cl/Cr is 9, 700 °C and 120 min). The underlying reaction mechanisms are as follows: (i) HCl produced by MgCl2·6H2O accelerates the destruction of Cr(VI)-LDH layer structure, completely exposing the incorporated Cr(VI), (ii) Cr(VI) is reduced to Cr(III) by Cl-, part of which is directly immobilized as MgCr2O4, and the other part generates CrCl3, which is volatilized or further combined with Mg2+ to form MgCr2O4. The total Cr leaching concentration of the practical COPR sample treated by this method dramatically decreases from 421 to 0.7 mg/L, well below the landfill standard limit (4.5 mg/L). This work provides an attainable strategy for thorough remediation of COPR and inspires the treatment of heavy metal-containing LDH.
Mg-Al-Cl layered double hydroxide (Cl-LDH) was prepared to simultaneously remove Cu(II) and Cr(VI) from aqueous solution. The coexisting Cu(II) (20mg/L) and Cr(VI) (40mg/L) were completely removed within 30min by Cl-LDH in a dosage of 2.0g/L; the removal rate of Cu(II) was accelerated in the presence of Cr(VI). Moreover, compared with the adsorption of single Cu(II) or Cr(VI), the adsorption capacities of Cl-LDH for Cu(II) and Cr(VI) can be improved by 81.05% and 49.56%, respectively, in the case of coexisting Cu(II) (200mg/L) and Cr(VI) (400mg/L). The affecting factors (such as solution initial pH, adsorbent dosage, and contact time) have been systematically investigated. Besides, the changes of pH values and the concentrations of Mg(2+) and Al(3+) in relevant solutions were monitored. To get the underlying mechanism, the Cl-LDH samples before and after adsorption were thoroughly characterized by X-ray powder diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. On the basis of these analyses, a possible mechanism was proposed. The coadsorption process involves anion exchange of Cr(VI) with Cl(-) in Cl-LDH interlayer, isomorphic substitution of Mg(2+) with Cu(2+), formation of Cu2Cl(OH)3 precipitation, and the adsorption of Cr(VI) by Cu2Cl(OH)3. This work provides a new insight into simultaneous removal of heavy metal cations and anions from wastewater by Cl-LDH.
