A study on the binding of important protein sources used in commercial fish fee with iron nanoparticles

The pursuit of alternative raw materials in commercial fish feed has been ongoing for the past two decades. In recent years, research has focused on the efficient digestion of potential raw material resources by fish, particularly those that reduce circular and carbon emissions. This thesis study investigates a micro and macro algae, as one of the innovative raw material sources and protein sources with potential for use in commercial fish feed. It is a preliminary study on iron nanoparticle production by Aurantiocthrium mangrovei and Spirulina sp. For this purpose, Spirulina sp. was obtained from a commercial company and Gracilaria sp. was obtained from Thailand in lyophilised dry form. Aurantiocthrium mangrovei samples were magnetised with iron oxide. Scanning Electron Microscopy (SEM) images and Energy Dispersive X-ray Spectroscopy (EDS) element analysis of magnetised and non-magnetised (control group) samples were performed for each specimen. These results demonstrated that, when compared to control groups, iron oxides were clustered at the nanoparticle level in SEM images, and the presence of iron oxides in the voids on the raw material was also confirmed by EDS analysis. According to the EDS elemental analysis results, no iron oxide was detected in the control groups; however, in magnetised Gracilaria sp. Aurantiocthrium mangrovei and Spirulina sp. samples, the presence of iron oxide was clearly evident, indicating that the process was successful. This thesis study has completed the initial investigations to demonstrate that innovative feed sources coated with iron oxide can be utilised more effectively by fish with iron ion, thereby enabling fish to derive greater benefit from these raw materials. Keywords: Nanoparticle, iron, digestibility, raw material, algae