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The incorporation of essential oils and nanotechnology into edible films has the potential to improve the microbiological safety of foods. The aim of this study was to evaluate the effectiveness of pullulan films containing essential oils and nanoparticles against 4 foodborne pathogens. Initial experiments using plate overlay assays demonstrated that 2% oregano essential oil was active against Staphylococcus aureus and Salmonella Typhimurium, whereas Listeria monocytogenes and Escherichia coli O157:H7 were not inhibited. Two percent rosemary essential oil was active against S. aureus, L. monocytogenes, E. coli O157:H7, and S. Typhimurium, when compared with 1%. Zinc oxide nanoparticles at 110 nm were active against S. aureus, L. monocytogenes, E. coli O157:H7, and S. Typhimurium, when compared with 100 or 130 nm. Conversely, 100 nm silver (Ag) nanoparticles were more active against S. aureus than L. monocytogenes. Using the results from these experiments, the compounds exhibiting the greatest activity were incorporated into pullulan films and found to inhibit all or some of the 4 pathogens in plate overlay assays. In challenge studies, pullulan films containing the compounds effectively inhibited the pathogens associated with vacuum packaged meat and poultry products stored at 4 °C for up to 3 wk, as compared to control films. Additionally, the structure and cross-section of the films were evaluated using electron microscopy. The results from this study demonstrate that edible films made from pullulan and incorporated with essential oils or nanoparticles may improve the safety of refrigerated, fresh or further processed meat and poultry products.

There has been a growing interest in the use of natural materials as a delivery mechanism for antimicrobials and coatings in foods. The aim of the present study was to evaluate the effectiveness of pullulan coatings to improve internal quality and shelf-life of fresh eggs during 10 wk of storage at 25 and 4 °C. Three treatments of eggs were evaluated as follows; non-coated (control; C), coated with pullulan (P), and coated with pullulan containing nisin (N). The effects of the pullulan coatings on microbiological qualities, physical properties, and freshness parameters were investigated and compared with non-coated eggs. For non-coated eggs, as storage time increased, yolk index, albumen index, and Haugh unit value decreased and weight loss increased. However, pullulan coatings (P or N) minimized weight loss (<1.5%) and preserved the albumen and yolk quality of eggs (with a final B grade) 3 wk longer than non-coated eggs at 25 °C. At 4 °C, both P- and N-coated eggs went from AA to A grade after 9 wk and maintained the grade for 10 wk (4 wk longer than that of non-coated eggs). This study is the first to demonstrate that pullulan coatings can preserve the internal quality, prolong the shelf-life, and minimize weight loss of fresh eggs.

Edible films containing antimicrobials are gaining importance as potential treatment to extend product shelf life and reduce risk of pathogens. Antimicrobial activities of pullulan films incorporated silver nanoparticles (Ag NPs) 100 nm, zinc oxide nanoparticles (ZnO NPs) 110 nm, oregano oil (OR) 2% and rosemary oil (RO) 2%, against Listeria monocytogenes and Staphylococcus aureus, were evaluated during the preparation and storage at 4, 25, 37, and 55°C up to 49 days in plate overlay assays (in vitro). Moreover, the prior pullulan films were applied directly on turkey deli meat were inoculated by L.monocytogenes and S. aureus and stored at 4 °C for two weeks. The results from this study demonstrate that Ag NPs and OR edible films more active than ZnO NPs and RO, respectively. The optimum conditions for storage pullulan edible films incorporated nanoparticles (NPs) and/or essential oils (EOs) were 4 and 25°C. Ag NPs, ZnO NPs, OR, and RO based films were exhibited significant effects as antibacterial activity against pathogens. These results revealed that (NPs) and/or (EOs) have a good potential to be incorporated into pullulan to make an antimicrobial edible film or coating for various food applications.

Objectives:To investigate the effect of Ramadan fasting on the symptoms of chronic heart failure with a reduced ejection fraction (HFrEF). Globally, more than one billion Muslims fast during Ramadan. Data regarding the effect of fasting in heart failure patients with a reduced ejection fraction are limited.Methods:We prospectively studied 249 outpatients with HFrEF who undertook Ramadan fasting at tertiary care cardiac center in Saudi Arabia in 2017. We obtained information regarding the clinical assessment, diagnosis, emergency department visits, and hospitalization during and in the month preceding Ramadan.Results:We enrolled 249 patients, 227 (91%) undertook the fast for the entire month. During Ramadan, 209 (92%) patients remained hemodynamically stable, whereas 18 (8%) developed instability. The mean New York Heart Association (NYHA) functional class was significantly lower in the stable than in the unstable group (1.46±0.7 vs. 3.22±0.55, p<0.0001), although no intergroup differences were observed before Ramadan. Patients from the unstable vs. the stable group showed significantly less adherence to medications (67% vs. 94%, p<0.0001) and to diet (39% vs. 79%, p<0.0001), and a lower likelihood of demonstrating ischemic cardiomyopathy as an underlying etiology of HFrEF (33% vs. 57%, p=0.046). Dependent t-test analysis including all patients showed that the NYHA classification before Ramadan was significantly higher than during Ramadan (2.19±0.9 vs. 1.6±0.8, t-value 8.5, p<0.0001).Conclusion:In most patients with chronic HFrEF, Ramadan fasting is considered safe. Non-adherence to medication and diet are significantly associated with decompensated heart failure during Ramadan.