Biogenic synthesis of gold nanoparticles using Sargassum tenerrimum and its evaluation of antibacterial activity against Escherichia coli and Salmonella typhi

1291-1297An important aspect of nanotechnology is the development of a reliable and ecofriendly method for the synthesis of nanomaterials. In the present study, Sargassum tenerrimum extract was used to synthesize gold nanoparticles (AuNPs) by the reduction of AuCl4− ions to Au0. The formation and morphology of the synthesized AuNPs were investigated using \UV–visible spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, X-ray diffraction, and field emission scanning electron microscopy with energy dispersive X-ray analysis. The nanoparticles synthesized at 60 °C were spherical in shape while few were also hexagonal in shape with the size ranging between 10 and 40 nm. The antibacterial activity of AuNPs was tested against Escherichia coli (ATCC 25922) and Salmonella typhi (ATCC 6539). On examination under an epifluorescence microscope, it was found to cause a significant amount of deterioration to the bacterial cells

In vitro anticancer activity of Sargassum sp. polysaccharides against MCF-7 cell lines

1267-1273Seaweed polysaccharides are compounds with promising chemopreventive and chemotherapeutic activities. In this study, polysaccharides isolated from Sargassum seaweeds were tested for their efficiency in cancer therapy. Polysaccharides were isolated, purified, and characterized using nuclear magnetic resonance (NMR); and Fourier transform infrared (FT-IR) spectroscopic and matrix-assisted laser desorption ionization mass spectrometric (MALDI-MS). It was found that the polysaccharides from Sargassum sp. branches are sulfated galactose–fucose disaccharides and sulfated galactose monosaccharides attached to the main chain through (1–4) linkages. Further, the polysaccharides were tested for cytotoxicity and anticancer activity against human breast adenocarcinoma cell line (MCF-7) using the Annexin-V/propidium iodide (PI) staining method