Green Synthesized Silver Nanoparticles Prepared from the Antimicrobial Crude Extracts of two Brown Seaweeds Against Plant Pathogens

Abstract

This study aimed for green synthesis of silver nanoparticles (Ag-NPs) from the antimicrobial crude extracted in chloroform: methanol(1:1 v/v) from the two brown seaweeds Spatoglossum asperum and Hedophyllum sessile active against two pathogenic bacteria (Xanthomonas axonopodis pv. citri and X. oryzae pv. oryzae) and a fungus Ustilaginoidea virens cause diseases in plants under in vitro assay. Crude extracts exhibit high antibacterial activity and low antifungal activity. Green synthesized Ag-NPs showed very high antimicrobial properties on comparing its crude extracts. Among the crudes, extract of Spatoglossum asperum exhibits higher bioactivity than the extract of Hedophyllum sessile but Ag-NPs prepared from the extract of H. sessile possess very strong bioactivity over Ag-NPs of Spatoglossum asperum. Reduction of Ag-NPs was confirmed by UV spectra. FTIR data indicate that active groups related to terpenoids and phenols found in the crude extracts were responsible for the reduction of Ag-NPs. The XRD data showed that the pure three types of crystal silver structure at 2θ values 32.51, 46.50 and 74.62 corresponding to 111, 200 and 220 planes for silver, respectively. This study concludes that chloroform: methanol (1:1 v/v) extracts of Hedophyllum sessile and Spatoglossum asperum containing active groups related to terpenoids and phenols and they are acting as reducing agents for green synthesis of silver nanoparticles which are potential source for controlling the plant pathogens studied.

Nanoencapsulation of basil essential oil alleviates the oxidative stress, genotoxicity and DNA damage in rats exposed to biosynthesized iron nanoparticles

“…Nowadays, nanotechnology seems a promising revolution in the construction and characterization of the functional properties of the nanoparticles to incur into different branches of sciences ( Jothirethinam et al., 2015 ). Basil (Ocimum basilicum L) is an herb widely used in folk medicine, food flavoring.…”

Extraction of Fucoidan from Turbinaria decurrens and the Synthesis of Fucoidan-Coated AgNPs for Anticoagulant Application

“…68,69 There are studies that have reported AgNPs synthesized using crude extracts of marine brown algae such as Sargassum wightii, 70 Turbinaria conoides, 71 and other seaweeds. 23,72,73 In this study, the synthesis of AgNPs by sulfated fucoidan isolated from the marine brown alga T. decurrens was confirmed based on the colorless solution of AgNO 3 turning brownish-yellow, indicating the formation of NPs, and monitored by the UV− visible spectral band at 420 nm (Figures 5a and S2). This band was identified as a "surface plasmon resonance band" attributed to the excitation of free electrons in the NPs.…”

“…NPs synthesized by selective biomolecules are considered to be most desired for target-specific biomedical applications rather than those synthesized from crude compounds. , There are studies that have reported AgNPs synthesized using crude extracts of marine brown algae such as Sargassum wightii, Turbinaria conoides, and other seaweeds. ,, In this study, the synthesis of AgNPs by sulfated fucoidan isolated from the marine brown alga T. decurrens was confirmed based on the colorless solution of AgNO 3 turning brownish-yellow, indicating the formation of NPs, and monitored by the UV–visible spectral band at 420 nm (Figures a and S2).…”

Nematocidal and Bactericidal Activities of Green Synthesized Silver Nanoparticles Mediated by Ficus sycomorus Leaf Extract

“…Many of the physical and chemical properties of nanoparticles can be controlled by choosing their size and shape. Since nanoparticles (NPs) could be used in optoelectronics, recording media, sensing devices, catalysis, and medicine, producing and studying them is an important area of research [ 2 ]. Chemical methods used to produce nanoparticles today cannot be used in biomedicine because they use toxic chemicals and produce harmful byproducts.…”

“…Biomimetic systems include the use of yeast, fungi, bacteria, plants, and other organisms to produce nanostructures of metals and semiconductors that are safe for living things. Silver nanoparticles (Ag-NPs) are becoming more popular as more pathogens become resistant to antibiotics [ 2 , 4 ]. As a possible antimicrobial agent, metallic silver in the form of nanoparticles has received significant attention [ 5 ].…”