Antimicrobial properties of promising Zn–Fe based layered double hydroxides for the disinfection of real dairy wastewater effluents

Abstract

Bacterial resistance to conventional antibiotics is a serious challenge that requires novel antibacterial agents. Moreover, wastewater from dairy farms might contain countless number of pathogens, organic contaminants and heavy metals that consider a threat to the terrestrial and aquatic environment. Therefore, the development of cost-effective, highly operation-convenient, recyclable multifunctional antimicrobial agents became an urgent necessity. Layered double hydroxides (LDH) have shown promising results as antibacterial agents. However, more work is required to further investigate and improve the antimicrobial performance of LDH structures against pathogens. In this study three Zn–Fe based LDH were investigated for real dairy wastewater disinfection. The three LDH samples were cobalt substituted Zn–Fe LDH (CoZnFe), magnesium substituted Zn–Fe LDH (MgZnFe) and MgZnFe-Triazol LDH (MgZnFe-Tz) nanocomposite. Seventy-five wastewater samples were collected from a dairy farm sewage system. The sensitivity of isolated pathogens was tested against two commonly used disinfectants (Terminator and TH4) and was assessed against the three LDH samples at different concentrations. The overall prevalence of S. agalactiae, S. dysgalactiae and Staph. aureus was significantly at 80.0% (P-value = 0.008, X2 = 9.700). There was variable degree of resistance to the tested disinfectants, whereas the antimicrobial activity of CoZnFe LDH was increased significantly at a concentration of 0.005 mg/L followed by MgZnFe LDH while MgZnFe-Tz LDH showed minor antibacterial potency. It was concluded that CoZnFe LDH showed a better biocidal activity in killing the isolated resistant pathogens, making it a good choice tool in combating the zoonotic microbes in wastewater sources.

Actinobacterium-Mediated Green Synthesis of CuO/Zn–Al LDH Nanocomposite Using Micromonospora sp. ISP-2 27: A Synergistic Study that Enhances Antimicrobial Activity

“…The remarkable properties of LDHs, such as their special layered structure, significant anion substitution capacity, high surface area, and high thermal stability, make them promising candidates for a wide range of applications, including as catalysts, photoresponsive materials, and drug carriers . Recent papers published in the open literature have investigated the antibacterial properties of LDH materials such as CuAl, , MgAl, − NiAl, ZnFe, , ZnMgFe, CoNiZnFe, CoAl, CuZnAl, and ZnAl. , …”

“…The novelty of our study lies in its specific focus on MO/LDH nanocomposites, which combine the advantageous properties of MO and LDHs (LDH). Although both MO ,, and LDHs ,, have individually exhibited antibacterial potential, the synergistic interactions and enhanced efficacy resulting from their combination remain largely unexplored. Through the investigation of MO/LDH nanocomposites, our study aims to bridge this gap in the literature by providing valuable insights into the combined antibacterial properties of these materials.…”

Investigation of ternary Zn–Co–Fe layered double hydroxide as a multifunctional 2D layered adsorbent for moxifloxacin and antifungal disinfection

“…This adsorbent showed a maximum adsorption capacity of 230.68, 133.29, and 57.34 mg/g for methyl orange, methylene blue, and malachite green, respectively. Furthermore, cobalt, and magnesium were incorporated in the binary ZnFe LDH to produce ternary ZnCoFe and ZnMgFe LDH respectively as reported by Abdel Aziz et al 12 . These ternary LDH samples were investigated for the disinfection of real dairy wastewater effluents.…”