Evaluation of UPF and antibacterial activity of cotton fabric coated with colloidal seaweed extract functionalized silver nanoparticles

Bioactive nanoparticles derived from marine brown seaweeds and their biological applications: a review

The biosynthesis of novel nanoparticles with varied morphologies, which has good implications for their biological capabilities, has attracted increasing attention in the field of nanotechnology. Bioactive compounds present in the extract of fungi, bacteria, plants and algae are responsible for nanoparticle synthesis. In comparison to other biological resources, brown seaweeds can also be useful to convert metal ions to metal nanoparticles because of the presence of richer bioactive chemicals. Carbohydrates, proteins, polysaccharides, vitamins, enzymes, pigments, and secondary metabolites in brown seaweeds act as natural reducing, capping, and stabilizing agents in the nanoparticle's synthesis. There are around 2000 species of seaweed that dominate marine resources, but only a few have been reported for nanoparticle synthesis. The presence of bioactive chemicals in the biosynthesized metal nanoparticles confers biological activity. The biosynthesized metal and non-metal nanoparticles from brown seaweeds possess different biological activities because of their different physiochemical properties. Compared with terrestrial resources, marine resources are not much explored for nanoparticle synthesis. To confirm their morphology, characterization methods are used, such as absorption spectrophotometer, X-ray diffraction, Fourier transforms infrared spectroscopy, scanning electron microscope, and transmission electron microscopy. This review attempts to include the vital role of brown seaweed in the synthesis of metal and non-metal nanoparticles, as well as the method of synthesis and biological applications such as anticancer, antibacterial, antioxidant, anti-diabetic, and other functions.

Evaluation of Brown and red seaweeds-extracts as a novel larvicidal agent against the deadly human diseases-vectors, Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus

Infectious diseases such as malaria, dengue, and yellow fever are predominantly transmitted by insect vectors like Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus in tropical regions like India and Africa. In this study, we assessed the larvicidal activity of commonly found seaweeds, including Padina gymnospora, P. pavonica, Gracilaria crassa, Amphiroa fragilissima, and Spatoglossum marginatum, against these mosquito vectors. Our findings indicate that extracts from P. gymnospora Ethyl Acetate (PgEA), P. pavonica Hexane (PpH), and A. fragilissima Ethyl Acetate (AfEA) displayed the highest larval mortality rates for A. stephensi, with LC50 values of 10.51, 12.43, and 6.43 μg/mL, respectively. Additionally, the PgEA extract from P. gymnospora exhibited the highest mortality rate for A. aegypti, with an LC50 of 27.0 μg/mL, while the PgH extract from the same seaweed showed the highest mortality rate for C. quinquefasciatus, with an LC50 of 9.26 μg/mL. Phytochemical analysis of the seaweed extracts revealed the presence of 71 compounds in the solvent extracts. Fourier-transform infrared spectra of the selected seaweeds indicated the presence of functional groups such as alkanes, alcohols, and phenols. Gas chromatography-mass spectrometry analysis of the seaweeds identified major compounds, including hexadecanoic acid in PgEA, tetradecene (e)- in PpEA, octadecanoic acid in GcEA, and 7-hexadecene, (z)-, and trans-7-pentadecene in SmEA.

Seaweed as a Natural Source against Phytopathogenic Bacteria

Plant bacterial pathogens can be devastating and compromise entire crops of fruit and vegetables worldwide. The consequences of bacterial plant infections represent not only relevant economical losses, but also the reduction of food availability. Synthetic bactericides have been the most used tool to control bacterial diseases, representing an expensive investment for the producers, since cyclic applications are usually necessary, and are a potential threat to the environment. The development of greener methodologies is of paramount importance, and some options are already available in the market, usually related to genetic manipulation or plant community modulation, as in the case of biocontrol. Seaweeds are one of the richest sources of bioactive compounds, already being used in different industries such as cosmetics, food, medicine, pharmaceutical investigation, and agriculture, among others. They also arise as an eco-friendly alternative to synthetic bactericides. Several studies have already demonstrated their inhibitory activity over relevant bacterial phytopathogens, some of these compounds are known for their eliciting ability to trigger priming defense mechanisms. The present work aims to gather the available information regarding seaweed extracts/compounds with antibacterial activity and eliciting potential to control bacterial phytopathogens, highlighting the extracts from brown algae with protective properties against microbial attack.

Recent Advances in Functionalization of Cotton Fabrics with Nanotechnology

Nowadays, consumers understand that upgrading their traditional clothing can improve their lives. In a garment fabric, comfort and functional properties are the most important features that a wearer looks for. A variety of textile technologies are being developed to meet the needs of customers. In recent years, nanotechnology has become one of the most important areas of research. Nanotechnology’s unique and useful characteristics have led to its rapid expansion in the textile industry. In the production of high-performance textiles, various finishing, coating, and manufacturing techniques are used to produce fibers or fabrics with nano sized (10⁻⁹) particles. Humans have been utilizing cotton for thousands of years, and it accounts for around 34% of all fiber production worldwide. The clothing industry, home textile industry, and healthcare industry all use it extensively. Nanotechnology can enhance cotton fabrics’ properties, including antibacterial activity, self-cleaning, UV protection, etc. Research in the field of the functionalization of nanotechnology and their integration into cotton fabrics is presented in the present study.

Functionalization of cotton fabrics with titanium oxide doped silver nanoparticles: Antimicrobial and UV protection activities

The target of our current work was designed to prepare titanium oxide doped silver nanoparticles (Ag/TiO₂ NPs) and their impact on the functionalization of cotton fabrics. Additionally, the effect of Ag/TiO₂ NPs was compared with the individually prepared silver nanoparticles (AgNPs) and titanium oxide nanoparticles (TiO₂ NPs). In this work, AgNPs was prepared in its solid state using Arabic gum as efficient stabilizing and reducing agent. Then, two concentrations of the as-synthesized nanoparticles were used for functionalize the cotton fabrics by pad-dry-cure treatment in the presence of fixing agent to increase the durability of treated cotton fabrics against vigorous washing cycles. The finding implied that the prepared nanoparticles were successfully synthesized in nano-size with spherical shape and homogeneity. The efficacy of the functionalized cotton fabrics with those nanoparticles were evaluated in terms of multifunctional properties including antimicrobial and UV Protection Factor (UPF) and the mechanical features before and after many washing cycles; 10, 15 and 20 times. The resultant also proved that Ag/TiO₂ NPs-treated cotton fabrics exhibited the greater values of both antimicrobial and UPF properties with enhancement in the tensile strength and elongation features. Thus, the combination between these two nanoparticles through doping reaction is suitable for imparting superior antimicrobial properties against the four tested microbial species (S. aureus, E. coli, C. albicans, and A. niger) and good UPF properties.

Bioinspired Nanomodification Strategies: Moving from Chemical-Based Agrosystems to Sustainable Agriculture

Agrochemicals have supported the development of the agricultural economy and national population over the past century. However, excessive applications of agrochemicals pose threats to the environment and human health. In the last decades, nanoparticles (NPs) have been a hot topic in many fields, especially in agriculture, because of their physicochemical properties. Nevertheless, the prevalent methods for fabricating NPs are uneconomical and involve toxic reagents, hindering their extensive applications in the agricultural sector. In contrast, inspired by biological exemplifications from microbes and plants, their extract and biomass can act as a reducing and capping agent to form NPs without any toxic reagents. NPs synthesized through these bioinspired routes are cost-effective, ecofriendly, and high performing. With the development of nanotechnology, biosynthetic NPs (bioNPs) have been proven to be a substitute strategy for agrochemicals and traditional NPs in heavy-metal remediation of soil, promotion of plant growth, and management of plant disease with less toxicity and higher performance. Therefore, bioinspired synthesis of NPs will be an inevitable trend for sustainable development in agricultural fields. This critical review will demonstrate the bioinspired synthesis of NPs and discuss the influence of bioNPs on agricultural soil, crop growth, and crop diseases compared to chemical NPs or agrochemicals.

Biosynthesis of silver nanoparticles using isolated Bacillus subtilis: characterization, antimicrobial activity, cytotoxicity, and their performance as antimicrobial agent for textile materials

Silver nanoparticles (AgNPs) have unique properties and a large range of applications. Biosynthesis of stable AgNPs using the extracellular filtrate of Bacillus subtilis was proved by the characteristic surface plasmon resonance at about 420-430 nm. They were polycrystalline with spherical, hexagonal, and irregular shapes and they were negatively charged (-40 mV) with an average diameter of 20 nm. FTIR spectrum confirmed the presence of protein molecules coating AgNPs. The optimum conditions for the synthesis of tested AgNPs were 1:6 filtrate dilution, 1 mM AgNO₃, pH 7, 30 °C , 48 h contact time under static and illuminating conditions. The synthesized AgNPs showed antibacterial activities against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus cereus, and Salmonella typhi, antifungal activity against Candida albicans and antiviral activity against rotavirus. Also, they showed potent cytotoxic effects on lung and hepatic carcinoma human cell lines. Meanwhile, the acute toxicity study against mice showed no significant changes in hematological, biochemical, and histological parameters of AgNPs treated mice. They also showed mild hepatoprotective effect in thioacetamide (TAA) - induced hepatic fibrosis in rats. AgNPs treated textiles fabrics showed high antimicrobial activities against different pathogenic microorganisms as well as UV protection adequacy.

New Generation of Antibacterial Products Based on Colloidal Silver

The main objective of the present paper is the green synthesis of colloidal silver by ultrasonication starting from silver nitrate and using soluble starch as the reducing agent. Soluble starch has been used during synthesis because it is a cheap and environmentally friendly reactive. Silver colloid has been characterized by physicochemical methods: UV–VIS spectroscopy, Scanning Electron Microscopy and Energy Dispersive X-Ray spectroscopy. This colloidal material was prepared in order to prove and establish its toxicity on heterotrophic bacteria. Toxicity tests were carried out using test cultures with and without silver colloid with different concentrations. This way was possible to establish the minimum silver concentration that presents a toxic effect against used bacteria. Quantitative evaluation of bacterial growth was performed by using the Most Probable Number method. By counting the bacterial colony number, the antibacterial effect was determined for colloidal silver deposited onto the cotton gauze by adsorption. During the present study, we optimized the adsorption specific parameters: solid:liquid ratio, temperature, contact time, colloidal silver concentration. By thermodynamic, equilibrium and kinetic studies, the adsorptive process mechanism was established.

Effect of Dispersion Solvent on the Deposition of PVP-Silver Nanoparticles onto DBD PlasmaTreated Polyamide 6,6 Fabric and Its Antimicrobial Efficiency

Polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNPs) dispersed in ethanol, water and water/alginate were used to functionalize untreated and dielectric barrier discharge (DBD) plasma-treated polyamide 6,6 fabric (PA66). The PVP-AgNPs dispersions were deposited onto PA66 by spray and exhaustion methods. The exhaustion method showed a higher amount of deposited AgNPs. Water and water-alginate dispersions presented similar results. Ethanol amphiphilic character showed more affinity to AgNPs and PA66 fabric, allowing better uniform surface distribution of nanoparticles. Antimicrobial effect in E. coli showed good results in all the samples obtained by exhaustion method but using spray method only the DBD plasma treated samples displayed antimicrobial activity (log reduction of 5). Despite the better distribution achieved using ethanol as a solvent, water dispersion samples with DBD plasma treatment displayed better antimicrobial activity against S. aureus bacteria in both exhaustion (log reduction of 1.9) and spray (methods log reduction of 1.6) due to the different oxidation states of PA66 surface interacting with PVP-AgNPs, as demonstrated by X-ray Photoelectron Spectroscopy (XPS) analysis. Spray method using the water-suspended PVP-AgNPs onto DBD plasma-treated samples is much faster, less agglomerating and uses 10 times less PVP-AgNPs dispersion than the exhaustion method to obtain an antimicrobial effect in both S. aureus and E. coli.

A Short Overview of Recent Developments on Antimicrobial Coatings Based on Phytosynthesized Metal Nanoparticles

The phytosynthesis of metallic nanoparticles represents an exciting new area of research, with promising perspectives, gaining in the last decades an increasing importance. Nanotechnology represents an important tool and an efficient option for obtaining particles with controlled morphology and shapes, phytosynthesized nanoparticles (NPs) being a good alternative to remove hazardous reagents. Due to the practical applications of the phytosynthesized nanoparticles, which are mainly associated with their antimicrobial potential, the abundance of scientific literature in this domain is given by researches in the phytosynthesis of metallic nanoparticles (3654 articles) and the evaluation of their antimicrobial properties (2338 papers). The application of phytosynthesized nanoparticles as antimicrobial coatings represented the subject of only 446 works, which lead us to the subject of this review paper. Application of antimicrobial coatings containing phytosynthesized nanoparticles for the development of antimicrobial textiles, other biomedical applications, protection of food (including fruits and vegetables), as well as for other types of applications based on their antimicrobial potential are covered by the present review.

In-situ green myco-synthesis of silver nanoparticles onto cotton fabrics for broad spectrum antimicrobial activity

In the realm of green synthesis of metals nanoparticles for medical textile application, silver nanoparticles (AgNPs) were biosynthesized in situ cotton fabrics for the first time by using fungi for rendering cotton fabrics antimicrobial activity with abroad range towards different pathogenic organisms. Herein, five different isolated fungi from medicinal plants were identified and optimized their growth media prior examined their ability to reduce Ag⁺ ions to AgNPs in-situ cotton fabrics along with ex-situ method. Synthesis of AgNPs were characterized by making use of instruments e.g. UV-vis spectroscopy, Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction (SAED), Scanning Electron Microscopy (SEM), and Fourier Transform Infrared (FTIR). Whereas antimicrobial activities of the resultant cotton fabrics were investigated against Gram positive (S. aureus ATCC29213), Gram negative (E. coli ATCC 25922), Yeast (C. albicans ATCC10321) and, fungi (A. niger NRC 53). Results revealed the successful biosynthesis of AgNPs using different fungus strains whether in-situ cotton fabrics or ex-situ manner. The size of the resultant AgNPs by ex-situ method were varied (5-20 nm). The antimicrobial activity of the in-situ treated cotton samples exhibited different behaviors towards both pathogenic bacteria and fungi. This manner opens up a new way to discover the ability of nanobiotechnology to provide world with substitutional aids mimic to synthetic materials.