Green synthesis and antibacterial properties of Thalassiosira-microalgae decorated with silver and lignin Nanoparticles: A promising strategy for bacterial control in aquaculture

Lignin nanoparticles (LNPs), as a special aggregate of renewable and biodegradable lignin available in abundant amounts, are a perfect building-block material because of their advantages, including good dispersibility in water, great biocompatibility, and eco-friendly characteristics. To exploit a promising method of producing LNPs, we developed a simple and sustainable synthesis approach using a recycled γ-valerolactone (GVL)/water binary solvent (GWBS). Up to 200 g/L lignin from several sources could be completely dissolved in GWBS. LNPs were easily obtained through nanoprecipitation (dropping or dialysis) of the lignin solution. The yield and size of LNPs can be controlled during nanoprecipitation. The highest yield of LNP reached 90% via dropping nanoprecipitation, and its relevant initial concentration was up to 24 g/L. This highly efficient dropping method might provide a method for scaled-up production of LNPs. The resultant LNPs, having a diameter of ca. 250 nm and a ζ-potential of −40 mV, also showed good dispersibility and stability in water. LNPs can stabilize essential oils and promote their growth inhibition activity against microbes. These results indicated that we also initiated a new method of achieving enhanced antimicrobials with whole biomass-based chemicals.

Improving barrier and antibacterial properties of chitosan composite films by incorporating lignin nanoparticles and acylated soy protein isolate nanogel

With the development of nanotechnology, gold nanoparticles (Au NPs) have attracted enormous attention due to their special properties. The green synthesis of Au NPs from lignin would inspire the utilization of lignin and its related functional materials. In this study, a rapid preparation process of Au NPs was investigated by utilizing lignin nanoparticles (LNPs) under room temperature without chemical addition. The LNPs acted as a reducing agent, stabilizing agent, and template for the preparation of LNPs@AuNPs. The obtained LNPs@AuNPs were characterized by UV-Vis spectrum, Transmission Electron Microscope (TEM), and X-ray photoelectron spectroscopy (XPS). The possible mechanism was illustrated by Fourier Transform Infrared Spectroscopy (FT-IR), 31P, XPS, and UV analyses. The abundant hydroxyl groups (24.96 mmol/g) favored the preparation of Au NPs. Au NPs diameters of 10–30 nm were well dispersed in the LNPs. The optimal reaction conditions were a ratio of 10 mg of LNPs to 0.05 mmol HAuCl4, room temperature, and a reaction time of 30 min. The LNPs@AuNPs exhibited excellent stability in the suspension for more than seven days. The reduction process could be related to the disruption of side chains of lignin, hydroxyl group oxidation, and hydroquinones and quinones from the comproportionation reaction. The LNPs@AuNPs would open a door for the design of Au NP/lignin-derived novel functional materials.

Lignin nanoparticles from hydrotropic fractionation of giant reed and eucalypt: Structural elucidation and antibacterial properties

Lignin nanofiller-reinforced composites hydrogels with long-lasting adhesiveness, toughness, excellent self-healing, conducting, ultraviolet-blocking and antibacterial properties

Green synthesis of multifunctional natural rubber-lignin nanocomposites: A sustainable approach for waste reduction

Green synthesis of high-performance seed tape using Camellia oleifera shells: DES-extracted nanolignin/chitosan composites for enhancing UV shielding and plant growth.

Background: Diabetes mellitus is a severe metabolic disease in which a person’s body cannot control the glucose level in the blood; it results from a defect in insulin secretion, insulin action, or both. Nanotechnology is a rising area in pharmaceutical sciences as nanoparticles are reported to enhance drug efficacy obtained from plant sources through green synthesis. Purpose: The purpose of this review is to focus on the antidiabetic potential of various metallic nanoparticles like silver, gold, copper, and selenium by using their secondary metabolites like tannins, alkaloids, saponins, and steroids. The advantages of green nanoparticle synthesis are that they are eco-friendly, high temperature is not required, can be used on large-scale synthesis, and are cost-effective. Methods: A preliminary search was conducted in PubMed, OVID Medline, Embase, ScienceDirect, Web of Science, and Google Scholar databases using keywords such as “Diabetes, nanoparticles, metallic nanoparticles, gold nanoparticles, silver nanoparticles.” Results: This review includes various marketed formulations of silver and gold nanoparticles particles obtained from various biological sources like allium cepa, argyreia nervosa, callophyllumtomentosum, punica granatum, cassia auriculate, saracaasoka, gymnemasylvestre, etc. along with their research findings for reducing the antidiabetic activity. Conclusion:This review contains details about the silver and gold nanoparticles obtained from various biological sources used to treat diabetes.

Polyvinyl alcohol/chitosan hydrogels with enhanced antioxidant and antibacterial properties induced by lignin nanoparticles

Binary and ternary poly(l-lactide) (PLLA)-based nanocomposites, containing nanolignin (1 wt %) and different metal oxide nanoparticles (0.5 wt %, Ag2O, TiO2, WO3, Fe2O3, and ZnFe2O4), were realized by solvent casting, and their morphological, thermal, surface, optical, antioxidant, and antimicrobial characterizations were performed. The presence of metal oxide nanoparticles at the selected weight concentration affects the surface microstructure of the PLLA polymer, and this outcome is particle-type dependent, according to the shape, morphology, and chemical properties of the selected nanoparticles (NPs). Analogously, wettability of PLLA-based nanocomposites was slightly modified by the presence of hydrophobic lignin nanoparticles and different shaped metal oxides. Results of differential scanning calorimetry (DSC) and X-ray powder diffraction (XRD) tests confirmed that nanoparticle addition confined the mobility of the amorphous phase, increasing at the same time the formation of more numerous but less perfect PLLA crystals. Interestingly, antioxidant activity was also obtained in ternary-based nanocomposites, where a synergic effect of lignin and metal oxide nanoparticles was obtained. Antibacterial tests showed manifest activity of TiO2 and Ag2O nanoparticles containing PLLA films, and the time dependence was more evident for Staphylococcus aureus than for Escherichia coli. Lignin nanoparticles are able to provide protection against UV light while still allowing visible light to pass and even surpass the UV-protection capacity provided by many inorganic nanoparticles. This makes them an attractive renewable additive for the realization of PLLA/metal oxide nanocomposites in the fields of food, drug packaging, and biomedical industry, where antibacterial and antioxidant properties are required.

Green synthesis approaches for the synthesis of nanomaterials and their different uses have been researched and garnered the interest of researchers in recent years (1-5). One excellent instrument for the introduction and advancement of nanotechnology is the green synthesis of noble metal nanoparticles. Because no hazardous or toxic chemicals are used during the plant-mediated synthesis process, also known as phytosynthesis, it is sometimes referred to as "green synthesis" (6, 7). In order to control the morphology, size, and stability of synthesised nano-sized structures, metallic nanoparticles can be prepared using a variety of synthesis techniques, including biological, physical, chemical, and others. However, the most intriguing synthesis method is the one for green metallic anoparticle synthesis. Plant extract-based green synthesis techniques have gained a lot of attention because they are both economical and environmentally friendly (8-10) and because a variety of abundant and diverse biomolecules function as reducing and capping agents (11, 12). Modifying the morphology, shape, size, surface to volume ratio, and composition of nanoparticles (NPs) is a crucial step towards achieving improved physical, chemical, and biological properties for desired applications in various fields, including electronics, household appliances, cosmetics, agriculture, and pharmaceuticals (13-17). Green synthesis methods facilitate this process. The safe and environmentally benign character of phytosynthesized silver nanoparticles (Ag NPs) makes them an attractive option for usage in a wide range of applications. Researchers are constantly looking for less dangerous, manageable, effective, large-scale manufacturing, and environmentally friendly synthesis techniques for nanotechnology advancements and their effects on biological things (18-21). Ag NPs are among the metals that have drawn the most attention from researchers because of their unique physiochemical characteristics and exciting potential uses in biomedicine (22-27). In order to lessen microbial contamination, the scientific community is making use of silver nanoparticles (Ag NPs) in nanomedicine and in combination with other biomaterials. Because of these nanoparticles' surface plasmon resonance feature, they have also been investigated for bio-imaging applications (28).

Green synthesis of lignin nanoparticle in aqueous hydrotropic solution toward broadening the window for its processing and application

Fabrication of lignin nanoparticles with adjustable size, antioxidant, antibacterial, and hydrophobic properties by a two-step fractionation.

Lignin nanoparticles as a promising nanomaterial for encapsulation of Rose damascene essential oil: Physicochemical, structural, antimicrobial and in-vitro release properties

Lignin nanoparticles-reduced graphene oxide based hydrogel: A novel strategy for environmental applications