Proporties and Synthesis of Biosilver Nanofilms for Antimicrobial Food Packaging.

In this original research, biodegradable corn starch (CS) and wheat gluten (wg)-based silver nanofilms were synthesized and analyzed by using goji berry extract taurine (ta), garlic extract (GC), whey powder (wh), and montmorillonite clay nanoparticles. Antibacterial-corn-starch-based nano films were analyzed by using the methods of high-performance liquid chromatography (HPLC), Fourier Transform infrared spectroscopy (FTIR-ATR), X-ray diffraction (XRD), dynamic and mechanical (DMA) analysis, and scanning electron microscopy (SEM). In addition, the antibacterial resistances of the corn starch nano films against the bacteria Salmonella and Staphylococcus aureus (S. aureus) and Listeria monocytogenes were examined and the migration assays were carried out. The migration analysis results of CS1, CS2, and CS3 nanocomposite films were found as 0.305, 0.297, and 0.297 mg/dm2, respectively. The inhibition zone of CS1, CS2, and CS3 nanocomposite films were found as 1547, 386, and 1884 mm2 against Salmonella bacteria. The results show that silver nanofilms are suitable as packaging films for the production of packaging in milk and dairy products, liquid foods, and acidic foods.

The antioxidant and antibacterial properties of chitosan encapsulated with the bee pollen and the apple cider vinegar.

In this study, the chitosan, a polysaccharide, was encapsulated with the bee pollen and the apple cider vinegar. The freeze-drying method was used in the encapsulation process. The freeze cooling temperature was determined as -80 °C. The obtained encapsulated chitosan compounds were analyzed by Fourier Transform Infrared Spectroscopy (FTIR) and their molecular weights were determined by the cryoscopy method. The total amount of the phenol compounds and % the antioxidant activity of the synthesized compounds were measured by UV spectrophotometer and, the loading capacity of the polyphenol compounds in encapsulation was determined. The success of encapsulation was calculated based on the % encapsulation efficiency (%EE) calculation. The antibacterial and the surface activity properties of the obtained CSx and CSy compounds were analyzed against Listeria monocytogenes, Staphylococcus aureus, E. coli and Salmonella bacteria using the well diffusion method and the Zeiss microscope.

Determination of theoretical calculations by DFT method and investigation of antioxidant, antimicrobial properties of olive leaf extracts from different regions.

In this study, we studied samples of mature olive leaves from the districts of Incirli Ova within the province of Aydin and the district of Fethiye in Mugla/Turkey. Several processes were carried out on the olive leaves to use them in this study, including drying under different conditions, determination of moisture, extract output, overall determination of phenols, antioxidant activity determination and anti-microbial assays. The chemicals that were used in the study were Folin's reagent and gallic acid for total phenolic assays, DPPH (1,1-diphenyl-2-picrylhydrazyl) and Trolox for antioxidant activity assays and nutrient broth and nutrient agar for antimicrobial testing. In the theoretical part of the study, the structures of oleuropein and Trolox molecules were examined, and their oxidation properties were aimed to be determined and compared to experimental results. According to the results of total phenolic assays, the phenol contents in the olive leaves from Aydin and Mugla were observed to be very close to each other. In the anti-microbial assay, it was observed that the samples of olive leaves from Mugla were more antioxidant than those from Aydin.

Investigation and preparation of biodegradable starch-based nanofilms for potential use of curcumin and garlic in food packaging applications.

In this study, biodegradable starch-based nano films were developed by turmeric extract curcuma longa (CC), octaphenyl-polyhedral oligomeric silsesquioxane (POSS), garlic extract with antibacterial properties (GC) and clay nanoparticles. Ag+-Mt-POSS-CC-CS, Mt-CC-CS and Mt-GC-CS nanofilms were synthesized as the final products. The antibacterial and surface-active corn starch-based nanofilms that were synthesized were analyzed by using the methods of X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and scanning electron microscopy (SEM). After this, the antibacterial resistances of the corn starch nanofilms against the bacteria Salmonella and Staphylococcus aureus (S. aureus) and their surface-active properties against the bacteria S. aureus, E. coli, Listeria monocytogenes and Salmonella were examined. The synthesized nano films were subjected to migration analyses, which are an important criterion for food packaging films, and their results were compared.According to the results of the analysis, while the starch nanofilms containing garlic showed antibacterial resistance against salmonella and S. aureus bacteria, the starch nano films containing curcumin and octaphenyl-POSS did not form an inhibition zone. Comparing surface activity properties, curcumin and octaphenyl-POSS-containing nano films showed surface activity, while the garlic-containing nanofilms did not show surface activity. This result shows that the mechanical properties of nanofilm containing garlic have given stronger results. Migration analysis results show that the synthesized nanofilm has found to suitable for use in the packaging of all food products such as milk products, fatty foods, liquid, acidic and dry foods according to the results of all migration analyses.

Synthesis and characterization of antibacterial bio-nano films for food packaging.

This study prepared antibacterial nanocomposite films for food packaging from Montmorillonite, which was modified by quaternary ammonium salts such as cetyltrimethylammonium bromide (CT), hexadecyl-tributyl phosphonium bromide (HD) and corn starch (CS). After this, it determined the antimicrobial activity of CS nanofilms against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria. Dispersion of silicate layers and starch nanocomposite films was analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM), and the results indicated that presence of quaternary ammonium salts enhanced clay dispersion, and the starch films incorporated with quaternary ammonium salts would provide potential use in food packaging as nanostructural materials. The nanofilms that were obtained based on the results of the antibacterial analysis were confirmed to have much stronger antibacterial properties than those in similar studies in the literature.