Suharyadi, Uun Yanuhar, Maheno Sri Widodo, Abdul Rahem Faqih, Heru Suryanto, Nico Rahman Caesar
Nanotechnology has rapidly developed in various fields. The unique, specific, and very small dimensions of nanoparticles have many functions in technical and biological advancements, such as drug delivery and antibacterial applications. This study investigates the potential antibacterial properties of chitosan-stabilized Fe3O4 nanoparticles (Fe3O4 NPs) to inhibit the growth of Vibrio harveyi bacteria and evaluates their toxicity towards white leg shrimp (Litopenaeus vannamei). The characterization results of the Fe3O4 NPs synthesis show an average crystallite size of 21.41 nm. The antibacterial activity of chitosan-capped Fe3O4 NPs colloidal (Cs/Fe3O4 NPs) was found at a chitosan concentration of 15,000 mg/L, with an inhibition zone against V. harveyi of 6.12 ± 0.02 mm, and Fe3O4 NPs colloidal without chitosan capping at 6.17 ± 0.01 mm. Both treatments showed significantly greater antibacterial activity (P < 0.05, n = 3) compared to the treatment with Fe3O4 NPs colloid capped with chitosan at 5,000 and 10,000 mg/L. The toxicity test was conducted on white leg shrimp at 48 h and 96 h of exposure, with the highest mortality occurring at a concentration of 125 mg/L, resulting in 5 % mortality (P > 0.05) with an LC50 value of 338.84 mg/L. Fe3O4 NPs have the potential to be developed as therapeutic agents or as bacterial growth inhibitors in the field of aquaculture by coating feed as a supplement (nano feed) due to their antibacterial properties and low toxicity levels towards cultured organisms. © 2025 The Authors
Doctoral Program, Faculty of Fisheries and Marine Sciences, Universitas Brawijaya Malang, Indonesia; Study Program of Aquatic Resource Management, Faculty of Fisheries and Marine Sciences, Universitas Brawijaya Malang, Indonesia; Aquaculture Study Program, Faculty of Fisheries and Marine Sciences, Universitas Brawijaya Malang, Indonesia; Center of Excellence for Cellulose Composite (CECCom), Department of Mechanical and Industrial Engineering, Faculty of Engineering, Universitas Negeri Malang, Indonesia; Aquaculture Technology Study Program, Politeknik Ahli Usaha Perikanan Jakarta, Indonesia
