GC–MS metabolomics profile of methanol extract of Acacia modesta gum and gum-assisted fabrication and characterization of gold nanoparticles through green synthesis approach

Abstract

<p>Hereunder, for the first time, we reported phytocompounds in the methanolic extract of <em>Acacia modesta</em> (AM) gum through Gas chromatography-mass spectrometry (GS-MS). Further, the AM gum aqueous solution was used for gold nanoparticles (AuNPs) synthesis through a simple, swift, eco-friendly, and less costly green synthesis approach. A total of 108 phytocompounds (63 with nonpolar, 45 with polar column) were identified in the gum extract, which includes fatty acids, alcohols, sterols, aldehyde/ketones, furans, aromatic compounds, esters, phenols, terpenes, sugar derivatives, alkaloids, and flavones. From three used concentrations (5, 10, and 15 mg/mL) of the AM gum aqueous solution, 15 mg/mL gum solution resulted in more successful AuNPs synthesis with a smaller size, which was visualized by a rusty red color appearance. UV-Visible absorption spectroscopy revealed the characteristic surface plasmon resonance (SPR) of AuNPs in aqueous solution at 540 nm. Dynamic light scattering (DLS) measurement of NPs solution revealed a hydrodynamic diameter of 162 ± 02 nm with the highest gum concentration where core AuNPs diameter was 22 ± 03 nm, recorded by Transmission electron microscopy. Zeta potential revealed fair stability of AuNPs that was not decreased with time. <span style="color:black">Catalytic activity experiments revealed that AM gum based AuNPs can increase the rate of the reduction of methylene blue 10 times in comparison with AM gum extract alone. </span>Results from this study showed that a diverse array of phytocompounds in AM gum can successfully reduce gold ions into gold nanoparticles, which can be used further in different pharmaceutical and industrial applications. </p>