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Zinc oxide nanoparticles have many advantages for nano-biotechnologists due to their intense biomedical applications. ZnO-NPs are used as antibacterial agents, which influence bacterial cells through the rupture of the cell membrane and the generation of reactive free radicals. Alginate is a polysaccharide of natural origin due to its excellent properties that are used in various biomedical applications. Brown algae are good sources of alginate and are used as a reducing agent in the synthesis of nanoparticles. This study aims to synthesize ZnO-NPs by using brown alga Fucus vesiculosus (Fu/ZnO-NPs) and also to extract alginate from the same alga, which is used in coating the ZnO-NPs (Fu/ZnO-Alg-NCMs). The characterizations of Fu/ZnO-NPs and Fu/ZnO-Alg-NCMs were determined by FTIR, TEM, XRD, and zeta potential. The antibacterial activities were applied against multidrug resistance bacteria of both gram-positive and negative. The results obtained in FT-TR showed there are some shifts in the peak positions of Fu/ZnO-NPs and Fu/ZnO-Alg-NCMs. The peak at 1655 cm−1, which assigned amide I-III, is present in both Fu/ZnO-NPs and Fu-Alg-ZnO-NCMs; this band is responsible for bio-reductions and stabilization of both nanoparticles. The TEM images proved the Fu/ZnO-NPs have rod shapes with sizes ranging from 12.68 to 17.66 and are aggregated, but Fu/ZnO/Alg-NCMs are spherical in shape with sizes ranging from 12.13 to 19.77. XRD-cleared Fu/ZnO-NPs have nine sharp peaks that are considered good crystalline, but Fu/ZnO-Alg-NCMs have four broad and sharp peaks that are considered semi-crystalline. Both Fu/ZnO-NPs and Fu/ZnO-Alg-NCMs have negative charges (−1.74 and −3.56, respectively). Fu/ZnO-NPs have more antibacterial activities than Fu/ZnO/Alg-NCMs in all tested multidrug-resistant bacterial strains. Fu/ZnO/Alg-NCMs had no effect on Acinetobacter KY856930, Staphylococcus epidermidis, and Enterobacter aerogenes, whereas there was an apparent effect of ZnO-NPs against the same strains. [ABSTRACT FROM AUTHOR]

One of the most prevalent chronic infectious disorders is tooth decay. Acids produced when plaque bacteria break down sugar in the mouth cause tooth decay. Streptococcus mutans and Lactobacillus acidophilus are the most prominent species related to dental caries. Innovative biocidal agents that integrate with a biomaterial to prevent bacterial colonization have shown remarkable promise as a result of the rapid advancement of nanoscience and nanotechnology. In this study, Ulva lactuca was used as a cellulose source and reducing agent to synthesize nanocellulose and Ulva/Ag/cellulose/nanocomposites. The characterizations of nanocellulose and Ulva/Ag/cellulose/nanocomposites were tested for FT-IR, TEM, SEM, EDS, XRD, and zeta potential. Ulva/Ag/cellulose/nanocomposites and Ulva/nanocellulose, both blended with fluoride, were tested as an antibacterial against S. mutans ATCC 25175 and L. acidophilus CH-2. The results of the SEM proved that nanocellulose is filament-shaped, and FT-IR proved that the functional groups of Ulva/nanocellulose and Ulva/Ag/cellulose/nanocomposites and cellulose are relatively similar but present some small diffusion in peaks. The TEM image demonstrated that the more piratical size distribution of Ulva/Ag/cellulose/nanocomposites ranged from 15 to 20 nm, and Ulva/nanocellulose ranged from 10 to 15 nm. Ulva/Ag/cellulose/nanocomposites have higher negativity than Ulva/nanocellulose. Ulva/Ag/cellulose/nanocomposites and Ulva/nanocellulose possess antibacterial activity against S. mutans ATCC 25175 and L. acidophilus CH-2, but Ulva/Ag/cellulose/nanocomposites are more effective, followed by that blended with fluoride. It is possible to use Ulva/Ag/cellulose/nanocomposites as an antimicrobial agent when added to toothpaste. It is promising to discover an economic and safe nanocomposite product from a natural source with an antimicrobial agent that might be used against tooth bacteria. [ABSTRACT FROM AUTHOR]

A huge amount of textile dyes are released as industrial waste into the environment each year, which alters the water's natural appearance and causes toxicity and carcinogenicity in the human body. Peanut husk is considered an agro-waste and contains many valuable compounds, such as cellulose. Different concentrations of cellulose were extracted from peanut husk and then loaded with bio-silver nanoparticles, which were fabricated using neem leaves (Azadirachta indica) as a reducing agent to form Ag-cellulose nanocomposites (Ag-Cell-NCMs). Different devices were used to characterize Ag-Cell-NCMs. The TEM images displayed that the size of Ag-Cell-NCMs ranged between 13.4 and 17.4 nm after dye adsorption. The Ag-Cell-NCMs were used to adsorb toxic dyes such as crystal violet (CV). Different parameters were applied, such as the ratio of cellulose to Ag-NPs, pH, contact time, adsorbent dose, dye concentration, and the temperature required to reach the optimization conditions to remove CV dye from the aqueous solution. Different kinetics and isotherm models were applied to the experimental data to explain the mechanism of the adsorption process. The adsorption of CV on Ag-Cell-NCMs follows the pseudo-second order, and the best-fit isotherm was the Langmuir isotherm. The new composite was tested for the possibility of dye desorption and ability to be reused several times, and we found that the new nanocomposite can be reused for multiple adsorptions and there is a possibility of dye desorption. [ABSTRACT FROM AUTHOR]

Mitomycin C (MMC) is an alkylating chemotherapy drug that could induce DNA damage and genetic alteration. It has been used as a model mutagen for in vivo and in vitro studies. The current study aimed to evaluate the protective role of Zinc oxide alginate–nanocomposites (ZnO-Alg/NCMs) against MMC–induced genotoxicity in mice. Animals were treated as follows: the control group, the groups treated with Algin (400 mg/kg b.w), the groups treated with ZnO-Alg/NCMs (400 mg/kg b.w), the group treated with MMC, and the groups treated with MMC plus Algin or ZnO-Alg/NCMs. Pre-treatment with Algin and ZnO-Alg/NCMs was repeated for one or seven days. Zinc oxide alginate-nanocomposites (ZnO-Alg/NCMs) were synthesized with the aim of incorporating the intrinsic properties of their constituents as an antigenotoxic substance. In this study, alginate was extracted from the brown marine alga Fucus vesiculosus, Zinc oxide nanoparticles were synthesized by using water extract of the same alga, and loaded in alginate to synthesize ZnO-Alg/NCMs. ZnO-NPs and ZnO-Alg/NCMs were characterized by TEM, SEM, EDX, and Zeta potential. The obtained results confirmed that by TEM and SEM, ZnO-NPs are rod shaped which modified, when loaded in alginate matrix, into spherical shape. The physical stability of ZnO-Alg/NCMs was reported to be higher than ZnO-NPs due to the presence of more negative charges on ZnO-Alg/NCMs. The EDX analysis indicated that the amount of zinc was higher in ZnO-NPs than ZnO-Alg/NCMs. The in vivo results showed that treatment with MMC induced genotoxic disturbances. The combined treatment with Algin and ZnO-Alg/NCMs succeeded in inducing significant protection against MMC. It could be concluded that ZnO-Algin/NCMs is a promising candidate to protect against MMC–induced genotoxicity. [ABSTRACT FROM AUTHOR]

Therapeutic selectivity is a critical issue in cancer therapy. As a result of its adjustable physicochemical characteristics, the Au/cellulose nanocomposite currently holds a lot of potential for solving this challenge. This work was designed to prepare a Au/cellulose nanocomposite with enhanced anticancer activity through the regulation of the mitogen-activated protein kinases (MAPK) signaling pathway. Nanocellulose, nanogold (AuNPs), and a Au/cellulose nanocomposite were biosynthesized from microgreen alga Chlorella vulgaris. Using UV-Vis absorption spectroscopy, transmission electron microscope (TEM), zeta potential analyzer, and Fourier transform infrared spectroscopy (FTIR), the synthesized nanoparticles were confirmed and characterized. In human alveolar basal epithelial cells (A549 cells), the selectivity and anticancer activity of the produced nanoparticles were evaluated. The cytotoxicity results revealed that the inhibitory concentration (IC50) of the Au/cellulose nanocomposite against A549 cancer lung cells was 4.67 ± 0.17 µg/µL compared to 182.75 ± 6.45 µg/µL in the case of HEL299 normal lung fibroblasts. It was found that treatment with nanocellulose and the Au/cellulose nanocomposite significantly increased (p < 0.05) the relative expression of tumor suppressor 53 (p53) in comparison to control cells. They also significantly (p < 0.05) decreased the relative expression of the Raf-1 gene. These findings indicate that nanocellulose and the Au/cellulose nanocomposite regulate cell cycles mostly via the motivation of p53 gene expression and reduction of Raf-1 gene expression. [ABSTRACT FROM AUTHOR]