Inhibitory Effect of Sodium Alginate Nanoemulsion Coating Containing Myrtle Essential Oil (Myrtus communis L.) on Listeria monocytogenes in Kasar Cheese

The present study aimed to characterize the physical properties of nanoemulsion-based sodium alginate edible coatings containing myrtle (Myrtus communis L.) essential oil and to determine its inhibitory effects on Listeria monocytogenes in fresh Kasar cheese during the 24-day storage at 4 °C. The GC-MS analysis showed that the main components of myrtle essential oil were 1,8-cineol (38.64%), α-pinene (30.19%), d-limonene (7.51%), and α-ocimene (6.57%). Myrtle essential oil showed an inhibitory effect on all tested L. monocytogenes strains and this effect significantly increased after ultrasonication. Minimum inhibitory and minimum bactericidal concentrations of myrtle essential oil nanoemulsion were found to be 4.00-4.67 mg/mL and 5.00-7.33 mg/mL, respectively. The antibacterial activity of myrtle essential oil nanoemulsion against L. monocytogenes was confirmed by the membrane integrity and FESEM analyses. Nanoemulsion coatings containing myrtle essential oil showed antibacterial activity against L. monocytogenes with no adverse effects on the physicochemical properties of cheese samples. Nanoemulsion coatings containing 1.0% and 2.0% myrtle essential oil reduced the L. monocytogenes population in cheese during the storage by 0.42 and 0.88 log cfu/g, respectively. These results revealed that nanoemulsion-based alginate edible coatings containing myrtle essential oil have the potential to be used as a natural food preservative.

Assessing the efficacy of polyvinyl alcohol/chitosan nanofibrous mat loaded with myrtle essential oil/gum Arabic in wound healing

Nowadays, extensive research has been conducted on electrospun nanofibers for wound dressing applications. Considering the growing concern over bacterial resistance to common antibiotics, investigating the potential of natural essential oils with antibacterial properties could prove to be beneficial in addressing this issue. In response to the challenges posed by impaired wound healing, we have designed a novel electrospun polyvinyl alcohol/chitosan nanofiber embedded with myrtle essential oil and gum Arabic dispersion (PVA/CS/MT-GA). The morphology and molecular structure of the prepared nanofibers were evaluated by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) analysis. The synthesized PVA/CS/MT-GA composite demonstrated a remarkable swelling capacity of 744% and exhibited acceptable mechanical strength. Additionally, the water vapor transmission rate (WVTR) of these nanofibers was obtained as 2497 g.m-2.day-1, which falls within the ideal range for wound dressings. The antimicrobial test results revealed that PVA/CS/MT-GA nanofibers exhibited notable antibacterial properties when tested against Escherichia coli and Staphylococcus aureus. The release profile of MT from MT-containing nanofibers exhibited a burst release mechanism in PVA/CS/MT-GA nanofibers, which can be beneficial in applications that require an immediate therapeutic effect. Furthermore, nanofibers as wound dressings in the full-thickness wound model of Wistar rats demonstrated a remarkable capacity to care for damaged tissue and promote faster healing times. Collectively, the results obtained in this study suggest that the developed nanofiber holds great promise as a potential candidate for wound dressing applications.