Assessing different extracts of Laurencia obtusa algae for the green fabrication of magnetic nanoparticles: their characterization and bioactivities.

This study aims to prepare magnetic nanoparticles from different extracts of Laurencia obtusa (L. obtusa) and to detect the composition, nutritional value, and lipoidal composition of L.obtusa. Based on the plant dry weight (DW), the extract had different concentrations of nine phenolic acids; the highest phenolic content was gallic acid and chlorogenic acid. According to HPLC analysis, the most abundant element in these plants was potassium (3.79 mg/g). GC-MS analysis revealed that methyl hexadecanoate was the major in the fatty acid profile, phytol was the major in the unsaponifiable profile (21.37%), and phytol was in the methanol extract (14.31%), and the major compound in the ethyl acetate extract was octacosane (47%). Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) were utilized to verify the synthesis of MNPs. The particles exhibited a spherical morphology with a diameter ranging from 6 to 22 nm. FT-IR confirmed the presence of functional groups, which reduced ions and stabilized MNPs. XRD confirmed the crystallinity of MNPs, and XPS confirmed the presence of peaks corresponding to Fe 2p, O 1 s, and C 1 s in the hybrids. According to bioactivities, 2,2-diphenyl-1-picrylhydrazylhydrate (DPPH) and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) tests demonstrated that MNPs from methanol have more activity than those of ethyl acetate. Furthermore, two examined MNPs have cytotoxic action against MCF-7 and HEPG-2 cell lines. Among two cell lines, MNPs derived from methanol exhibit higher activity than those derived from ethyl acetate. Lastly, our results indicated a rise in the proliferation of the chosen L.obtusa algae, which is abundant in phenolics, minerals, and other healthy substances that have health benefits.