Antibiotic resistance is a formidable global threat. Wastewater is a contributing factor to the prevalence of antibiotic-resistant bacteria and genes in the environment. There is increased interest evident from research trends in exploring nanoparticles for the remediation of antibiotic-resistant bacteria. Cobalt oxide (Co₃O₄) nanoparticles have various technological, biomedical, and environmental applications. Beyond the environmental remediation applications of degradation or adsorption of dyes and organic pollutants, there is emerging research interest in the environmental remediation potential of Co₃O₄ nanoparticles and its nanocomposites on antibiotic-resistant and/or pathogenic bacteria. This review focuses on the recent trends and advances in remediation using Co₃O₄ nanoparticles and its nanocomposites on antibiotic-resistant or pathogenic bacteria from wastewater. Additionally, challenges and future directions that need to be addressed are discussed.

Nanotechnology offers innovative approaches to improve ruminant nutrition by enhancing feed efficiency, nutrient utilization, animal health, and environmental sustainability. This review highlights the use of nano-minerals, nano-encapsulated bioactives, enzyme nano-particles, and nano-sensors to optimize rumen function, digestion, and immunity. Nano-minerals provide high bioavailability at lower doses and may replace antibiotics. Encapsulated compounds like essential oils, probiotics, and vitamins improve rumen fermentation and product quality. Nanotechnology allows precise nutrient delivery through encapsulation, chelation, and nano-packaging without affecting feed sensory properties. Nano-particles are classified as inorganic, organic, or complex nano-structures and are synthesized using physical, chemical, or biological methods. While promising, nanotechnology adoption must address concerns related to safety, environmental impact, and cost. Robust risk assessments and regulatory frameworks are essential. Overall, nanotechnology represents a powerful tool for advancing sustainable and profitable ruminants, and continued multidisciplinary research is needed to fully realize its benefits and ensure its responsible application in animal agriculture.

Bacteria are continually exposed to stressors, making their ability to sense, acclimate and adapt to changing conditions essential for fitness. Two-component response systems (TCRS) play a primary role in mediating these responses. However, the role of epigenetic modifications in acclimation and adaptation is not well understood. We characterized N6-methyladenine (6mA) and N4-methylcytosine (4mC) DNA methylation patterns in wild-type Escherichia coli K-12 MG1655, four cusS mutants and six silver-adapted mutants with and without exposure to 50 ng/mL AgNO₃ for 1 h using Single-Molecule Real-Time sequencing. The cusS mutants were selected to study the impact of the mutations on DNA methylation. Global mean 6mA fractions were high across all strains with and without silver and were largely driven by the dominant GATC motif in all strains and the AACN₆GTGC/GCACN₆GTT motif in wild-type and silver-adapted mutants, while global mean putative 4mC fractions were lower. Across conditions, variation was observed in extended degenerate motifs with moderate-to-low methylation. Our findings suggest that motif-specific methylation patterns vary across silver exposure and genetic backgrounds, while global methylation levels in E. coli remain remarkably resilient. This study improves understanding of microbial stress adaptation and stress response, raising the possibility that methylation contributes to TCRS-mediated stress tolerance.