Nickel oxide nanoparticles from Sargassumwightii: Synthesis, Characterization, and biomedical applications

Antimicrobial resistance and cancer claim millions of lives each year, making it important to find effective medications. The current study focuses on the rapid and sustainable manufacture of nickel oxide nanoparticles using Sargassum wightii aqueous extract (SW-NiO NPs) as a novel antibacterial and anticancer agent. The presence of phytochemicals in the Sargassumwightii in all extract was qualitatively screened and water extract, which is found to contain abundant phytochemical was used for the biosynthesis. Thus synthsized SW-NiO nanoparticles was characterised by UV-Visible, FT-IR, XRD, SEM, and TEM spectral studies, and then screend for its invitro anti microbial activity against bacterial strains (E. coli, K. pneumoniae, S. aureus, and B. subtilis) and fungal activity with the fungus strains (C. albicans, C. tropicalis),invitro anticancer and larvicidal activity. The SW-NiO NPs possessed cubic and hexagonal structures with an average crytallite size of 15-20 nm, according to the results of the analytical characterization. SEM and TEM analysis confirms the spherical like morphology and their respective elemental composition were identified by EDAX studies. The antimicrobial activity was carried by well diffusion method.Compared to gram -negative organisms, gram -positive species were more vulnerable to the SWNiO NPs with the zone of inhibition 17 mm. The fungal activity results showed the zone of inhibition 16 and 14 mm. It was also found that SW-NiO NPs inhibit the growth of tested fungus at higher doses. The cytotoxicity studies with liver cancer cell line through MTT assay revealed the inhibition value at 52.25 +/- 0.05 mu M, indicating their sensitivity to the HepG2 cell line. SW-NiO NPs made with water extract showed the highest larvicidal activity and 88.33 % death of Aedes agypti(AE). The LC50 and LC90 values for SW-NiO NPs against Aedes agypti (AE) larvae are found to be 31.420 and 134.261 ppm, respectively. The findings of the antimicrobial, larvicidal and invitro anticancer screening of this work provide compelling evidence that SW-NiO NPs made from an aqueous extract of Sargassum wightii have considerable biological applications which can be explored in detail on identifying the potential phyto constituents which are responsible for the activity.