Bactericidal and In-Vitro Cytotoxic Efficacy of Silver Nanoparticles (Ag-NPs) Fabricated by Endophytic Actinomycetes and Their Use as Coating for the Textile Fabrics

Abstract

An endophytic strain of Streptomyces antimycoticus L-1 was isolated from healthy medicinal plant leaves of Mentha longifolia L. and used for the green synthesis of silver nanoparticles (Ag-NPs), through the use of secreted enzymes and proteins. UV–vis spectroscopy, Fourier-transform infrared (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and dynamic light scattering (DLS) analyses of the Ag-NPs were carried out. The XRD, TEM, and FT-IR analysis results demonstrated the successful biosynthesis of crystalline, spherical Ag-NPs with a particle size of 13–40 nm. Further, the stability of the Ag-NPs was assessed by detecting the surface Plasmon resonance (SPR) at 415 nm for one month or by measuring the NPs surface charge (−19.2 mV) by zeta potential analysis (ζ). The green-synthesized Ag-NPs exhibited broad-spectrum antibacterial activity at different concentrations (6.25–100 ppm) against the pathogens Staphylococcus aureus, Bacillus subtilis Pseudomonas aeruginosa, Escherichia coli, and Salmonella typhimurium with a clear inhibition zone ranging from (9.5 ± 0.4) nm to (21.7 ± 1.0) mm. Furthermore, the green-synthesized Ag-NPs displayed high efficacy against the Caco-2 cancerous cell line (the half maximal inhibitory concentration (IC50) = 5.7 ± 0.2 ppm). With respect to antibacterial and in-vitro cytotoxicity analyses, the Ag-NPs concentration of 100 ppm was selected as a safe dose for loading onto cotton fabrics. The scanning electron microscopy connected with energy-dispersive X-ray spectroscopy (SEM-EDX) for the nano-finished fabrics showed the distribution of Ag-NPs as 2% of the total fabric elements. Moreover, the nano-finished fabrics exhibited more activity against pathogenic Gram-positive and Gram-negative bacteria, even after 10 washing cycles, indicating the stability of the treated fabrics.

Green Synthesis of Silver Nanoparticles Using the Flower Extract of Abelmoschus esculentus for Cytotoxicity and Antimicrobial Studies

“…38 As previously reported, the antibacterial properties of NPs are caused by the partial dissolution of the bacterial cell wall due to charge effects between the negatively charged cell wall and the positively charged silver nanomaterial. 39 It has also been reported that the interaction of silver nanoparticles with phosphorylated or sulfur proteins present in the cell wall of bacteria destabilizes and depolarizes the bacterial cell membrane, affecting the integrity of the membrane and leakage of H + . 40 The antibacterial mechanisms of action of AgNPs may be their interactions with the microbial membrane, which could lead to the rearrangement of membrane-bound organelles, destruction of the membrane and death of microbial pathogens.…”

Green Synthesis of Zinc Oxide Nanoparticles (ZnO-NPs) Using Arthrospira platensis (Class: Cyanophyceae) and Evaluation of their Biomedical Activities

“…Green synthesis is preferred over chemical and physical methods because of its eco-friendly, cost-effectiveness, easy handling, upscaling, and biocompatibility [ 6 ]. Recently, several NPs are synthesized by green methods such as Ag, Au, Cu, CuO, ZnO, Se, and others that are integrated into different biological activities [ 8 , 9 , 10 ]. Biogenic or green synthesized nanoparticles offer a promising alternative antimicrobial and anticancer agent for more safe, specific, and economic drugs or drug vehicle in drug delivery.…”

Antibacterial, Antifungal and Antibiofilm Activities of Silver Nanoparticles Supported by Crude Bioactive Metabolites of Bionanofactories Isolated from Lake Mariout

“…Bacteria-mediated synthesis of NPs, which is classified among such green synthesis approaches, poses the potential to substitute physicochemical means. It is characterized by an environmentally friendly nature, biocompatibility behavior, energy saving and lowering the risk of global warming [9][10][11].…”

“…Recently, it was also listed as bionanofactories by endowing simultaneous reduction and functionalization for the as-synthesized NPs in one single pot and without additional successive steps in a cost-effective way. Whereas, it reduces metal salt and converts it to its nanostructure in oxidation-reduction reaction via their biomolecules, meanwhile encompassing the as-synthesized NPs and serving as capping and functionalizing agents [9,10,18,19].…”