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Abstract

In this study, it is aimed to encapsulate some functional components of the olive leaves. Olive leaf extract was encapsulated using solution of sodium alginate, sodium alginate/gelatine, and sodium alginate/agar as wall material by ionic gelation technique. Also, olive leaf extract was encapsulated using solution of gelatine as wall material by cold gelation technique. The viscosities of the coating materials used in the study were investigated. An optimisation process was carried out to determine the injection time to be applied in the ionic gelation technique and the encapsulation efficiencies, particle sizes, swelling ratios, in vitro release profiles, and antioxidant activities of the obtained capsules were determined. While the encapsulation efficiency of the capsules obtained by the cold gelation technique was determined as the highest (98.2 ± 0.99%), it was revealed that the viscosity of the wall material used in the ionic gelation technique was important in the encapsulation efficiency. The particle size and swelling rate of the capsules obtained using the cold gelation technique were the highest. The release rate of oleuropein was generally higher at gastric pH than at intestinal pH. A correlation was found between antioxidant activities and the encapsulation efficiency of capsules.

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Abstract

A large amount of waste, especially the outer part of citrus fruits (peel), is generated after consuming the pulp and it remains unused. The valorisation of this waste by recovering its bioactive compounds seems interesting. The aim of this study was to find the optimal conditions using ultrasound-assisted extraction (UAE) that yield the highest carotenoid content and better antioxidant activity from Citrus reticulata Blanco peels.

Response surface methodology (RSM) through Box–Behnken experimental design was used to optimise the conditions for carotenoid extraction using UAE. Hexane concentration, temperature, and sonication time were selected as the main factors.

The results revealed that all independent variables affected the responses. The optimal UAE conditions for hexane concentration, temperature, and sonication time were 60.76%, 36.45 °C, and 37.32 min, respectively. The values of total carotenoid content (TCC) and total antioxidant activity (TAA) obtained by UAE were higher than those obtained by the maceration extraction method.

It can be concluded that the medium and extraction parameters, including hexane concentration, temperature, and sonication time, significantly influenced the recovery of carotenoids and antioxidant activity. The optimisation study allowed determining the appropriate conditions to maximise both responses. Compared to conventional maceration, the UAE method was superior and more efficient for extracting carotenoids from C. reticulata Blanco peels.

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Abstract

Food allergies became a major public health and food safety interest in the past decades as their prevalence is increasing, and their only available treatment is a strict elimination diet that necessitates appropriate food labelling regulations. While such regulations are available worldwide, most of them are not taking into account inadvertent allergen cross-contamination and they usually do not define threshold doses that could support the industry in their endeavour to provide reliable food labels for allergic consumers. This resulted in the proliferation of the “may contain” type precautionary allergen labelling (PAL), which is voluntary and is intended to warn consumers for potential unintended contamination with an otherwise undeclared allergen. As this kind of labelling is hardly ever based on actual risk assessment, it puts both the industry and the consumer into a difficult position. A promising tool towards the solution of this problem could be allergen threshold doses based on clinical data, which are becoming increasingly available. This review intends to present this process, the new ways of improved risk assessment it opens, and its implications for food analysis.

Open access

Abstract

The aim of this study was to evaluate the possibility of storage of mangoes (Mangifera indica L.) coated with chitosan-based nano-silver films. Chitosan-based nano-silver films were first made using chitosan with three degrees of deacetylation of 70, 80, and 90%. The films were then used for coating the mango fruits. All coated mangoes and the control samples were stored at 12 °C in a cooling room. The respiration rate, ethylene production rate, weight loss, firmness, total soluble solids, total acid, vitamin C, total sugar, and change of peel colour were evaluated once every 5 days during the storage period. As observed, the coating using the chitosan-based nano-silver films did not induce significant negative alterations on most of the physical characteristics and chemical constituents of the fruits. In addition, the coating using those materials helped reduce the respiration and the ethylene gas production and retard the ripening process of mango fruits. The chitosan-based films with higher deacetylation degrees (CN80 and CN90) better moderated the respiration of mangoes. The coating using chitosan-based nano-silver films prolonged the shelf-life of mangoes (up to 35 days) compared to the control (less than 10 days).

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Abstract

Background

Early identification of COVID-19 (coronavirus disease of 2019) by diagnostic tests played an important role in the isolation of infectious patients and management of this pandemic. Various methodologies and diagnostic platforms are available. The current “gold standard” for SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) diagnosis is real-time reverse transcriptase‐polymerase chain reaction (RT-PCR). To overcome the limitations posed by the short supply experienced early during the pandemic and to increase our capacity, we assessed the performance of the MassARRAY System (Agena Bioscience).

Methods

MassARRAY System (Agena Bioscience) combines RT-PCR (reverse transcription-polymerase chain reaction) with high-throughput mass spectrometry processing. We compared the MassARRAY performance to a research-use-only E-gene/EAV (Equine Arteritis Virus) assay and RNA Virus Master PCR. Discordant results were tested with a laboratory-developed assay using the Corman et al. E-gene primers and probes.

Results

186 patient specimens were analyzed using the MassARRAY SARS-CoV-2 Panel. The performance characteristics were as follows: the positive agreement was 85.71%, 95% CI (78.12 – 91.45), and the negative agreement was 96.67%, 95% CI (88.47 – 99.59). 19/186 (10.2%) results were found to be discordant and assessed by a different assay with the exception of 1, where the sample was not available for repeat testing. 14 out of 18 agreed with the MassARRAY after testing with the secondary assay. The overall performance after discordance testing was as follows: the positive agreement was 97.3%, 95% CI (90.58 – 99.67), and the negative agreement was 97.14%, 95% CI (91.88 – 99.41).

Conclusion

Our study demonstrates that the MassARRAY System is an accurate and sensitive method for SARS-CoV-2 detection. Following the discordant agreement with an alternate RT-PCR test, the performance was found to have sensitivity, specificity, and accuracy exceeding 97%, making it a viable diagnostic tool. It can be used as an alternative method during periods when real-time RT-PCR reagent supply chains are disrupted.

Open access

Abstract

The aim of this study was to isolate lactic acid bacteria (LAB) from artisanal cheeses and evaluate their probiotic potential and antibiotic susceptibility under in vitro conditions. Cheeses obtained at different maturation times were analysed for moisture and lipid contents, as well as for the presence of various microorganisms, including coagulase positive staphylococci, Salmonella spp., Escherichia coli, Listeria monocytogenes, filamentous fungi, yeasts, total mesophilic bacteria, and LAB. After identification, the selected LAB were subjected to human gastrointestinal tract (HGT) conditions to evaluate their survival rates. Of the 18 Lactobacillus strains isolated, 11 survived the HGT test and presented γ-haemolysis. No resistance was observed against antibiotics. Lactobacillus fermentum C1a, C1b, C1c, and C1f, as well as Lactobacillus paracasei C1d, C1e, and C1g, were identified as potential starter cultures for the food industry.

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Abstract

Obesity and other unhealthy behaviors are behind cardiovascular morbidity and mortality, with the Roma population particularly at risk. The aim of our cross-sectional (questionnaire- and physical measurements-based) study was to compare the prevalence of obesity in Hungarian, Romanian, and Slovakian Hungarian-speaking Roma and non-Roma (N = 1893) in relation to lifestyle-related risk factors for cardiovascular diseases (CVD). In the total sample, the proportion of extreme obesity was higher in Roma (P < 0.001) than non-Roma. The mean waist circumference was the highest in Hungary (P < 0.001). Visceral fat was higher in the Hungarian Roma sample than in the Slovak (P = 0.006) or Romanian Roma samples (P = 0.005). Hungarian Roma total cholesterol levels were lower than in the Slovak (P < 0.001) or Romanian samples (P < 0.001). Hypertension and cholesterol levels were associated with a higher risk among non-Roma men (P < 0.001), and the presence of smoking increased CVD risk among both men (P = 0.024) and women (P < 0.001) in the Roma minority. The combined presence of several risk factors was found mainly in Roma. Overall, Roma scores were found to be worse, but ethnicity did not provide clear evidence for the questions examined, but rather the level of education, which is associated with socioeconomic status.

Open access