Using brine shrimp to assess the performance of Annona muricata–zinc oxide nanoparticles: characterization and evaluation of photocatalytic, antibacterial and antibiofilm properties

The development of multifunctional nanoparticles through green synthesis is an important advancement in nanotechnology, addressing the growing need for effective antimicrobial agents against drug-resistant pathogens and efficient photocatalysts for environmental remediation, while also necessitating thorough eco-toxicological assessments to ensure their safe application, particularly in sensitive ecosystems like fisheries. In this study, we investigated the antimicrobial activities, photocatalytic activity and eco-friendly assessment on zooplankton crustacean Artemia salina and phytochemical properties of biosynthesized zinc oxide nanoparticles using aqueous fruit extract of Annona muricata (Am-ZnO NPs). The synthesized Am-ZnO NPs was characterized using UV–visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM). XRD analysis revealed the crystalline nature of Am-ZnO NPs. TEM analysis showed that the Am-ZnO NPs were spherical in shape with a size between 50 and 100 nm. In addition, Am-ZnO NPs showed antibacterial and antibiofilm activity against multiple drug resistance (MDR) Gram positive, Enterococcus faecalis bacteria. Am-ZnO NPs showed significant photocatalytic activity against two different organic dye pollutants namely methylene blue and acridine orange under both sunlight and UV light exposure. Ecotoxicity assessment of Am-ZnO NPs (25, 50, 75, and 100 μg mL–1) showed no toxicity against non-targeted marine crustacean Artemia salina at low concentration and slightly toxic at high concentration (100 μg mL–1). Together, the results suggest the potential application of Am-ZnO NPs against multiple drug resistance microbes and photocatalytic activities.