Antimicrobial, Antioxidant, and Anticancer Activities of Biosynthesized Silver Nanoparticles Using Marine Algae Ecklonia cava

Abstract

Green synthesis of silver nanoparticles (AgNPs) has gained great interest as a simple and eco-friendly alternative to conventional chemical methods. In this study, AgNPs were synthesized by using extracts of marine algae Ecklonia cava as reducing and capping agents. The formation of AgNPs using aqueous extract of Ecklonia cava was confirmed visually by color change and their surface plasmon resonance peak at 418 nm, measured by UV-visible spectroscopy. The size, shape, and morphology of the biosynthesized AgNPs were observed by transmission electron microscopy and dynamic light scattering analysis. The biosynthesized AgNPs were nearly spherical in shape with an average size around 43 nm. Fourier transform-infrared spectroscopy (FTIR) analysis confirmed the presence of phenolic compounds in the aqueous extract of Ecklonia cava as reducing and capping agents. X-ray diffraction (XRD) analysis was also carried out to demonstrate the crystalline nature of the biosynthesized AgNPs. Antimicrobial results determined by an agar well diffusion assay demonstrated a significant antibacterial activity of the AgNPs against Escherichia coli and Staphylococcus aureus. Antioxidant results determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay revealed an efficient antioxidant activity of the biosynthesized AgNPs. The biosynthesized AgNPs also exhibited a strong apoptotic anticancer activity against human cervical cancer cells. Our findings demonstrate that aqueous extract of Ecklonia cava is an effective reducing agent for green synthesis of AgNPs with efficient antimicrobial, antioxidant, and anticancer activities.

Phlorotannins

“…Phlorotannins (Fig. 1) are commonly isolated from the seaweeds, particularly brown algae, through conventional organic solvent isolation followed by chromatographic techniques to purify the compounds Koivikko et al, 2007;Venkatesan, Kim, & Shim, 2016). Furthermore, nuclear magnetic resonance spectroscopy is widely used to characterize the structure of compounds.…”

“…HILIC (Hydrophilic interaction chromatography) was demonstrated to be an effective separation mode, particularly for low molecular weight phlorotannins (Steevensz et al, 2012). Mature thalli contained (3) fucodiphlorethol G; (4) phlorofucofuroeckol A; (5) 7-phloroeckol; (6) dieckol; (7) 6,6 0 -bieckol; (8) triphlorethol-A; and (9) 2,7 0 -phloroglucinol-6,6 0 -bieckol (Venkatesan, Kim, & Shim, 2016).…”

<em>Botryococcus braunii</em> as a bioreactor for the production of nanoparticles with antimicrobial potentialities

“…After an 8-hour incubation, NP formation was confirmed via ultraviolet-visible (UV-Vis) spectroscopy, with the characteristic peak indicating the surface plasmon resonance at 400 nm (Figure 2). 31 The solution's color changed from green to dark brown, indicating the reduction of the silver nitrate. The total incubation time for all the experiments was set at 48 hours.…”

Cyclic voltammetry, photocatalytic and antimicrobial comparative studies of fabrication Fe3O4 and Fe3O4/PAN nanofibers

“…Antibacterial activity was optimum against Salmonella pathogens at 1.4 g of Fe 3 O 4 NP's substitution with PAN. The observed antibacterial activity of the synthesized nanoparticles from pomegranates peel could imply its ability to alter the formation of ROS, DNA replication, aggregation of proteins and interfere with 0leakages in the cell wall of bacterial pathogens [57][58][59].…”