Introduction: Selenium, a trace element with vital antioxidant and cancer-preventive properties, poses toxicity risks at higher doses, which can be mitigated through the green synthesis of nanoparticles using plant phytochemicals as natural reducing and stabilizing agents. This study aimed to investigate the potential of Morus rubra (L.) leaf extract as an effective natural reducing agent for the green synthesis of selenium nanoparticles, with an emphasis on their chemical characterization and assessment of biological activities. Methods: The synthesized SeNPs were characterized using UV-Vis spectroscopy, FTIR, XRD, and TEM. Antimicrobial activity was evaluated using the agar well diffusion method, and MIC was determined by broth microdilution assay. Cytotoxic effects were assessed using the MTT assay, and apoptosis was evaluated using AO/EB dual staining. Results: An absorption peak at 275 nm confirmed successful SeNP biosynthesis, yielding 10–60 nm crystalline nanoparticles. The SeNPs exhibited potent antioxidant activity (IC50 56.12 μg/mL), strong antimicrobial effects (largest inhibition 24 mm for B. subtilis; MIC 50–80 μg/mL), and selective cytotoxicity against MDA-MB-231 cancer cells (IC50 23.09 μg/mL), with higher tolerance in normal cells (IC50 50.16 μg/mL). AO/EB staining indicated that 70–80% of treated cancer cells underwent apoptosis. Discussion: These findings indicate that Morus rubra-mediated selenium nanoparticles align with recent advances in green nanotechnology, where plant extracts enhance both the safety and functional performance of nanoparticles. Conclusion: The biosynthesized selenium nanoparticles using Morus rubra leaf extract demonstrated efficient antioxidant, antimicrobial, and selective anticancer activities, highlighting their promising potential for biomedical applications.
Rocha et al. (Tue,) studied this question.