Plants uptake and assimilate nitrogen from the soil in the form of nitrate, ammonium ions, and available amino acids from organic sources. Plant nitrate and ammonium transporters are responsible for nitrate and ammonium translocation from the soil into the roots. The unique structure of these transporters determines the specificity of each transporter, and structural analyses reveal the mechanisms by which these transporters function. Following absorption, the nitrogen metabolism pathway incorporates the nitrogen into organic compounds via glutamine synthetase and glutamate synthase that convert ammonium ions into glutamine and glutamate. Different isoforms of glutamine synthetase and glutamate synthase exist, enabling plants to fine-tune nitrogen metabolism based on environmental cues. Under stressful conditions, nitric oxide has been found to enhance plant survival under drought stress. Furthermore, the interaction between salinity stress and nitrogen availability in plants has been studied, with nitric oxide identified as a potential mediator of responses to salt stress. Conversely, excessive use of nitrate fertilizers can lead to health and environmental issues. Therefore, alternative strategies, such as establishing nitrogen fixation in plants through diazotrophic microbiota, have been explored to reduce reliance on synthetic fertilizers. Ultimately, genomics can identify new genes related to nitrogen fixation, which could be harnessed to improve plant productivity.

Feathers are the most prevalent agricultural waste generated by chicken farms, polluting the environment and wasting protein resources as a result of the accumulation of large amounts of feathers. Therefore, keratinase-producing microorganisms represent a promising potential technique for the degradation of feather waste. Streptomyces netropsis A-ICA and Bacillus subtilis ALICA, previously isolated from the rhizosphere of desert plants (Larrea tridentata and Prosopis juliflora) respectively, were assessed for their feather-degradation ability. Keratinase activity was optimized using various parameters, including incubation time, pH, temperature, and feather concentration. The maximum keratinase activity of S. netropsis A-ICA and B. subtilis ALICA (113.6 ± 5.1 and 135.6 ± 4.1 U/mL) was obtained at the 5th and 3rd day of incubation with initial pH of 7.0 and 7.5 at 25 and 30 °C, and 1% (w/v) of chicken feather, respectively. Under the optimized conditions, the concentration of soluble protein in the feather hydrolysate reached 423.3 ± 25 and 565.3 ± 7.7 µg/mL, with feathers weight loss of 84 ± 2 and 86± 1.5% by S. netropsis A-ICA and B. subtilis ALICA, respectively. The highest disulphide bond reductase activity reached 10.7 ± 0.4 and 10.96 ± 1.1 U/mL, after five and three days of inoculation with S. netropsis A-ICA and B. subtilis ALICA, respectively. Furthermore, the antioxidant activity of feather protein hydrolysate obtained by S. netropsis A-ICA and B. subtilis ALICA was evaluated using DPPH radical-scavenging activity, which exhibited a significant antioxidant potential with an IC₅₀ value of 0.8 and 0.6 mg/mL. The 3D models of detected keratinases in both strains showed high similarity with subtilisin family. Further, the docking results clarified the importance of GSG and VVVFTP domains in B. subtilis and beta-keratin, respectively. The present study revealed the keratinolytic potential of S. netropsis A-ICA and B. subtilis ALICA in chicken feather degradation, which have potential application value and may be exploited as supplementary protein and antioxidant in animal feed formulations.

Zinc oxide nanoparticles (ZnO NPs) have gathered interest because of their unique characteristics and potential applications. In the current work, ZnO NPs underwent an eco-friendly biosynthesis process using garlic peel extract. The biosynthesized ZnO NPs were characterized using different analyses including Ultraviolet-visible (UV-vis) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FTIR). The produced ZnO NPs exhibited a UV–vis spectrum absorption peak at 365 nm, thus indicating the formation of ZnO NPs. The SEM showed that the biosynthesized ZnO NPs had an irregular surface morphological shape with an average size of 17 nm, according to the DLS analysis. Based on the FTIR findings, the bioactive functional groups responsible for stabilizing and capping the ZnO-NPs were confirmed. The biosynthesized ZnO NPs exhibited 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and antimicrobial activities against Gram-positive (Bacillus cereus) and Gram-negative bacteria (Klebsiella pneumonia). Therefore, the plant-mediated biosynthesized ZnNPs can be considered a promising candidate as an antioxidant and antimicrobial agent against pathogenic microbes found in different areas such as food safety and agriculture. Through the utilization of bioinformatics, we identified six potential targets for drug development in K. pneumonia and B. cereus, along with their corresponding interacting residues with zinc oxide nanoparticles. Additionally, our research revealed that the zinc oxide nanoparticles exhibited binding capabilities with the sulfiredoxin domain located at the specific targets of K. pneumonia, a crucial mechanism responsible for the repair of bacterial cells under oxidative stress.

As processed meat products, sausages have been criticized for their short shelf life. In this study, the impact of purslane (Portulaca oleracea L.) and chicory (Cichorium intybus L.) leaf extracts on the physicochemical and microbiological quality indices, chemical quality parameters, and antioxidant properties of goat meat sausages (GMSs) was evaluated. The added extracts enhanced storage stability and improved the overall acceptability of all treated GMS samples, meanwhile reducing the total volatile nitrogen (TVN) values over the cold storage period (4°C/40 days) compared to the control samples. Using plant extracts at 0.2% and BHT at 0.02% (w/w) led to concentration‐dependent decreases in thiobarbituric acid–reactive substance (TBARS) values and the microbial count in GMSs stored at 4°C for 40 days. The combination treatment of chicory and purslane (MPO + MCI) had the highest antioxidant and antimicrobial activity. Chicory and purslane leaf extracts are promising natural, safe, and inexpensive additives for producing high‐quality goat meat sausages, and their application can be extended to other processed meat products.