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In recent years, the synthesis of nanofibers using plant extracts and bioactive materials has been extensively studied and recognized as a suitable and efficient method applicable in the food packaging field. In this research, an antimicrobial material was introduced by the immobilization of glucose oxidase (GOx) in Nylon–Ag masterbatch/chitosan/Rosmarinus officinalis extract nanofiber via electrospinning technology. Nylon–Ag masterbatch/chitosan/Rosmarinus officinalis composite nanofibrous membranes with an average diameter of 207 ± 18 nm were successfully prepared using the electrospinning technique. The chemical properties of membranes were analyzed by Fourier transform infrared spectroscopy (FTIR) and the morphological characterization of nanofibers was evaluated with field emission scanning electron microscopy (FE-SEM). Moreover, enzymatic activity of GOx was determined by the Carmine method. FTIR results showed the successful incorporation of glucose oxidase and Rosmarinus officinalis into the nanofiber composite. Immobilized GOx showed high (79.5%) enzymatic activity in the optimum sample. The Rosmarinus officinalis, glucose oxidase-incorporated Nylon–Ag masterbatch/chitosan nanofibrous exhibited excellent antimicrobial activity on both gram-negative bacterium Escherichia coli (97.5%) and gram-positive bacterium Staphylococcus aureus (99.5%). The antibacterial and antioxidant Nylon–Ag masterbatch/chitosan/Rosmarinus officinalis/GOx nanofibrous membrane showed higher potential, compared to the control sample, to be used as food packaging by improving the shelf life and maintaining the quality of food stuffs. Therefore, this research recommends it as a promising candidate for food preservation applications. [ABSTRACT FROM AUTHOR]

Green synthesis of nanoparticles is a safe and cost-effective process for creating nanoparticles using extracts from different parts of plants, such as flowers, leaves, stems, and roots. In this research, Melissa Officinalis L. (MO) aqueous extract was used for the synthesis of Selenium nanoparticles (Se NPs) for the first time. These extracts contain flavonoids, polyphenols, and alkaloids, which act as reducing agents in synthesizing nanoparticles. In this study, the extract serves both as a reducing agent and a capping agent during the fast and simple green synthesis of Selenium nanoparticles. The hydrodynamic size of the nanoparticles was investigated by using DLS. Further characterization of the shape and size of the nanoparticles was conducted through SEM and TEM studies. Moreover, the elemental composition of the NPs was identified through Energy Dispersive X-ray (EDX) elemental analysis. Microscopy analysis results showed that the Se NPs had a spherical shape. Furthermore, the particle size was determined to be 65 nm and 34 nm via DLS and SEM studies, respectively. Additionally, the biological evaluation of Se NPs demonstrated a non-toxic effect on the Human Umbilical Vein Endothelial Cells (HUVEC) normal cell line and anticancer activity on the MCF-7 breast cancer cell line. [ABSTRACT FROM AUTHOR]

Zeolites are three-dimensional, microporous, crystalline solids with well-defined structures that contain aluminum, silicon, and oxygen in their form. Cations and water are located in the pores of zeolites. They have a framework structure, in which interconnected cavities are occupied by large metal cations (positively charged ions), and water molecules. The formation of specific zeolites can occur by more than one crystallization pathway. Control in the crystallization pathway can lead to the formation of different species. In this study, two new zeolite nanocomposites were synthesized using fixed raw materials including solvent, reagent (which acts as a template in the formation of zeolite morphology), silica source, and sodium hydroxide alkali. "MCM-22" mesoporous was first synthesized and then a new morphology of "MCM-22" was synthesized by changing the temperature, time, and amount of water. Also, two nanocomposites "ZSM-12 & 35 Composite" and "Zeolite Al-mordenite & ZSM-39 Composite" were synthesized with very different properties in terms of surface to volume ratio, acidity, specific surface area, ratio of Si to Al, and three-dimensional crystal structure. Various characterization techniques were used to provide information to better understand the structural properties of crystalline zeolites. They were then characterized, and analyzed using X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Fourier-Transform Infrared Spectroscopy (FTIR), Energy-Dispersive X-ray Spectroscopy (EDS), Mapping, and BET/BJH (Brunauer-Emmett-Teller (BET) and Barret-Joyner-Halenda (BJH)) techniques. The results showed that the synthetic zeolites, despite having the same precursors, differed in terms of surface to volume ratio, acidity, specific surface area, Si/Al ratio, and three-dimensional crystal structure. [ABSTRACT FROM AUTHOR]