In this paper, by employing an eco-friendly and green approach, semiconductor CuO/ZnO nanocomposite are synthesized using an aqueous extract of Urtica urens. FT-IR, XRD, TEM, SAED, EDX, TGA, and UV-Vis spectroscopy were used for semiconductor characterization. The data revealed the successful formation of crystalline spherical nanocomposites with sizes ranging from 5 to 45 nm. The main components of the synthesized nanocomposites were Cu, Zn, and O, which had different weights and atomic percentages. The maximum absorbance of nanocomposites was 358 nm, with a direct bandgap of 2.25 eV, which is suitable for photocatalysis under visible light. The maximum photocatalytic activity of the synthesized semiconductor nanocomposites for photodegradation of methylene blue dye was 95.8%, where it was 44.5% and 65.5% for monometallic CuO and ZnO, respectively. The optimum conditions for maximum photocatalytic activity were a pH of 9, a dye concentration of 5 mg L⁻¹, and nanocomposite concentration of 1.0 mg mL⁻¹ after 70 min. The reusability of the synthesized semiconductor was promising for the fourth cycle, with a reduced capacity of 5%. Complementary investigations, antimicrobial activity and cytotoxic activity, were performed to increase the application of semiconductor nanocomposites. The data revealed the promising activity of the nanocomposite against E. coli, P. aeruginosa, B. subtilis, S. aureus, C. parapsilosis, C. albicans, and C. tropicalis with low MICs ranging between 50 and 25 µg mL⁻¹. Additionally, compared with normal cell line, the synthesized nanocomposite targeted the cancer cell line HepG2 with a low IC50 value of 69.9 µg mL⁻¹ (vs. IC50 220 µg mL⁻¹ of normal cell line HFB4). Overall, the green-synthesized semiconductor CuO/ZnO nanocomposite showed promising activity as environmental contaminant cleaner and was integrated with antimicrobial and in vitro cytotoxic activities.

This research aimed to examine the dual effects of Coffea arabica on the cell division of Allium cepa and its antibacterial properties. This was achieved by utilizing the A. cepa bioassay to study mitosis and measuring optimal density, as well as using the agar well diffusion method to evaluate the antibacterial effect against Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis. To study the impact of Coffea arabica on mitosis, root tips of Allium cepa were exposed to three different levels of coffee (1.5, 5.5, and 10.5 g/100 ml). The frequency of chromosomal aberrations (CA) and mitotic index (MI) were observed under a microscope. For the antibacterial effect, the coffee extracts were tested against P. aeruginosa, S. aureus, and B. subtilis using two methods. First, the optimal density of bacterial growth was measured for three different coffee levels (3, 12.5, 20 mg/ml). Second, the agar well diffusion method was used to evaluate the size of the inhibition zones around the wells containing the coffee extract. The results revealed that Coffea arabica at levels of 10.5 g/100 ml and 5.5 g/100 ml significantly affected mitosis in A. cepa root cells, leading to an increase in CA, such as multinucleated cells, chromosomal stickiness, and chromosomal bridges. The MI was also noticeably elevated at these levels. Regarding antibacterial activity, P. aeruginosa was found to be the most susceptible to coffee at 12.5 mg/ml, as indicated by the optical density measurement. The agar well diffusion method showed that S. aureus exhibited the largest inhibition zone (1.9 cm) at 20 mg/ml. This research highlights the dual impact of Coffea arabica on both chromosomal stability and bacterial growth. The coffee extract demonstrated a clear effect on mitosis, causing CA and surged MI in A. cepa root cells. Additionally, coffee exhibited antibacterial properties, particularly against P. aeruginosa and S. aureus. These findings suggest that while coffee has beneficial antimicrobial effects, its impact on cellular processes, such as chromosomal integrity, should also be considered in future studies.

This work offers a sustainable and environmentally friendly way to create silver nanoparticles (AgNPs) by employing pomegranate peel extract (PPE) as a natural stabilizing and reducing agent. When silver nitrate was added, the color changed visibly from pale yellow to dark orange, indicating the reduction of silver ions and the creation of PPEAgNPs. The produced nanoparticles were found to be semi-spherical, crystalline, and of high purity using characterization techniques such as Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). They also had distinct diffraction peaks that corresponded to the (111), (200), (220), (311), and (222) lattice planes. According to antibacterial tests, PPE-AgNPs have a strong inhibitory effect on Salmonella typhimurium, Listeria monocytogenes, and Staphylococcus aureus, three important food-borne and clinical pathogens. The most noticeable inhibitory zones were seen at higher doses (10 mM), indicating that the antibacterial activity was dose-dependent. Furthermore, it was shown that exposure to light increased the antibacterial efficiency of PPE-AgNPs. This is probably because photoactivation processes boost the generation of reactive oxygen species (ROS), which in turn enhances the breakdown of bacterial membranes. These results support the use of agro-waste-based nanotechnology in the environmental and biomedical fields and highlight the potential of PPE-AgNPs as powerful, light-responsive antibacterial agents.