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Abstract

Nanoparticles can be synthesised by several methods. Due to the long duration, high cost, and toxic by-products of chemical and physical methods, the biological method has become more preferred. Among various sources such as bacteria, fungi, or yeast, the use of plants in biological synthesis has proven to be the most ideal. Many metals can be used in the biological method, including copper oxide (CuO). In this study, copper oxide nanoparticles (CuONPs) were synthesised using Pimpinella anisum L. aqueous extract. For characterisation of the CuONPs, UV–Visible Spectroscopy (UV–Vis), Scanning Electron Microscopy (SEM), Energy Dispersion Spectroscopy (EDS), and Fourier Transform Infrared Spectroscopy (FT-IR) analyses were performed. The biological activity of the P. anisum extract and CuONPs was determined using DNA cleavage (agarose gel electrophoresis), antioxidant (1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and hydrogen peroxide scavenging activity), mutagenic (Ames/Salmonella test), and catalytic (methylene blue degradation) activities. In DNA cleavage activity test, CuONPs completely denatured DNA at high concentrations (100 and 200 μg mL−1) due to their oxidative activity. The results showed that both the extract and CuONPs have antioxidant properties in DPPH and hydrogen peroxide scavenging activities. According to the mutagenicity, CuONPs did not have a mutagenic effect. In catalytic activity, CuONPs degraded methylene blue within 240 min by 99.45%.

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In this study, the odour values of rosemary, mint, black cumin, lavender, and thyme oils were determined by an electronic nose working with an Arduino microprocessor. The components of the plants were compared with the sensor data, and the most sensitive sensors were determined by sorting according to the highest components. The study data indicated that the MQ3 sensor exhibited the highest sensitivity for thyme, black cumin, and lavender oils, which contain 63% carvacrol, 38% thymoquinone, and 36% linalool, respectively. Also, MQ7 was the most sensitive sensor for menthone (68%) in mint oil and eucalyptol (45%) in rosemary oil. In addition, a low-cost and non-contact device that works with an infrared sensor has been developed to detect the identity of the oil added into the vial. The study data showed that low-cost Arduino-based IR and odour sensors can determine the identity and component percentage of oils. The fact that the developed device can detect with 100 percent accuracy even in case of peppermint and rosemary oils, which are very similar in appearance, shows that the study data will be an inspiration for contactless determination of oil quality and type.

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Abstract

The effect of different drying methods (oven drying, fluid bed drying, and freeze drying) on the fatty acid composition, astaxanthin content, antioxidant activity, and colour values of giant red shrimp (Aristaeomorpha foliacea) processing wastes were investigated. These results showed that freeze drying was the most effective method in preserving the quality of shrimp processing waste (SPW), resulting in higher levels of EPA and DHA, astaxanthin content, antioxidant activity, and desired reddish colour characteristics compared to other methods. These findings highlight the potential of freeze drying as a suitable technique for converting SPW into high value products.

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Abstract

The present work aimed to study the yeast communities of whole crop corn silages (CS) that were previously contaminated with aflatoxin-producing Aspergillus flavus (CSCA). In addition, the effect of lactic acid bacterium (LAB) inoculation on the aflatoxin B1 (AFB1) content, genotoxicity, yeast load, and diversity of yeast communities were also investigated. In A. flavus contaminated silages, after two months, the AFB1 content was 40% lower with LAB inoculation, also a lower level of genotoxicity was determined. The number of yeasts cultured from the initial mixture of chopped whole crop corn was 4.8 × 107 CFU g−1 wet mass, while only 2.4 × 106 CFU g−1 from the CSCA and 7.1 × 105 CFU g−1 from the LAB-inoculated CSCA could be cultured. Based on 144 randomly isolated strains, the yeast community of the initial mixture consisted of 8 species. In contrast, the yeast community of CSCA consisted only of 4 species determined by 132 randomly selected isolates. LAB-inoculated CSCA consisted also of 4 species based on 158 randomly isolated strains. Saccharomyces cerevisiae and Pichia kudriavzevii proved to be predominant in the CSCA, while S. cerevisiae and Meyerozyma guilliermondii were the most abundant in the LAB-inoculated CSCA. The species richness was also confirmed by alpha diversity values (1.827, 1.188, and 1.123 as Shannon's indices for CS, CSCA, and LAB-inoculated CSCA, respectively). In response to LAB inoculation, the species diversity decreased considerably.

Open access

Abstract

This study aims to predict drought periods affecting the Tokaj-Hegyalja wine region and the application of this in crop protection. The Tokaj-Hegyalja wine region is the only closed wine region in Hungary with a specific mesoclimate and a corresponding wine grape variety composition, in which climate change strongly threatens cultivation. The probability that a randomly selected day in the vegetation period will fall into a drought period in the future was estimated using the daily precipitation amount and daily maximum temperature data from the Hungarian Meteorological Service for the period 2002–2020. The Markov model, a relatively new mathematical method for the statistical investigation of weather phenomena, was used for this. Markov chains can, therefore, be a valuable tool for organizing integrated pest management. This can be used to plan irrigation, control fungal pathogens infecting the vines, and plan the success of a given vintage.

Open access

Abstract

Food manufacturing and processing are part of the nation's critical infrastructure. Due to the recent global spread of the SARS-CoV-2 virus, the potential contamination of the food chain and the resulting public health implications are of high consequence to society. The current primary food manufacturing and processing facilities already have various mechanisms such as hazard analysis and critical control point (HACCP) system in place. However, the widespread microbial infections in these facilities raise concerns that they will not only threaten the welfare of food processing workers, but also have a potentially greater consequence on the public if the food is contaminated with an infectious agent.

Despite the increasingly recognised role of the environment in the spread of microbes, the effect of air properties remains poorly understood. Heating, ventilation, and air conditioning (HVAC) systems in meat processing facilities not only provide a means of transport for viruses and bacteria but may also deposit them on surfaces where they can survive for days. To maintain a stable and safe food chain supply during the pandemic, the challenges to ensure safe food supply and protect the workers' health must be quickly addressed through sustainable, safe and economic approaches. With these two imminent challenges in mind, the overall goal of this review article is to provide a comprehensive overview of the role of the environment in the impaction and resuspension of bioaerosols, focusing on airborne bacteria and viruses. The review includes the latest results of modeling the spread of microbial aerosols in the airflow and the development of preventive measures to mitigate virus contamination in the unique environment of meat processing operations. By understanding how the environmental factors and seasonality affect the infectivity and spread of airborne pathogens, mitigation measures can be designed to minimise future infections within and beyond these facilities.

Open access

Abstract

The effect of the storage conditions of light (presence; absence) and relative humidity (50%; 75% RH) on the water content and colour of Porphyridium cruentum microalga powder was studied, then two packaging materials, low-density polyethylene (PE-LD) and metallised polyethylene terephthalate with polyethylene (PETmet/PE), were used to study their effect on the water content, colour, total carotenoids and chlorophylls contents, total phenolic content (TPC), and antioxidant activity (ABTS, DPPH, ORAC) of P. cruentum during storage at 23 °C and 50% RH. An atmosphere with 50% RH is recommended to minimise the water vapour absorption and lightness loss. In addition to the expected light protection, PETmet/PE material protected P. cruentum powder also against water absorption, contrary to PE material. There were no relevant colour changes of the microalga during storage in PETmet/PE. Regarding the total content of carotenoids and the antioxidant activity of the microalga, no significant differences were found between the biomasses stored in either packaging material. The TPC and DPPH values were practically constant during two months of storage, while ABTS and ORAC decreased more than 50% and 20%, respectively, during this time.

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Abstract

The utilization of sea buckthorn pomace (SBP) is attracting growing attention since it is valuable industrial waste. This pomace can find usage as a functional ingredient of food because it contains bioactive, health-promoting components, but to our knowledge, few scientists have so far studied utilization of the antimicrobial activity of fruit pomace. The study aims are to broaden our knowledge of antioxidant and antimicrobial status of SBP by utilizing pomace as a functional apple juice ingredient and by monitoring the antioxidant capacity, the total polyphenol content and microbial changes that occur during the storage of juice samples. Our results of this study highlight that the importance of the utilization of SBP because the results reported here provide further evidence that SBP can contribute to increasing the content of valuable components in apple juice samples and inhibiting the growth of microorganisms during storage.

Open access

Abstract

A novel magnetic molecular-imprinted polymer (MMIP) was used to selectively extract folic acid directly from real samples. Folic acid was used as template molecule, Fe3O4/SiO2-3-triethoxysilyl-propyl-acrylamide as functional monomer, azobisisobutyronitrile as initiation, ethylene glycol dimethacrylate as crosslinker agent, and acrylamide as the secondary monomer in a mixed ethanol-water solvent. The effect of different parameters on the extraction efficiency was studied, and the optimum conditions were established as follows: the concentrations of crosslinking and template were fixed at 0.05 and 0.06 g, absorption percentage was 96.5, pH was adjusted to 8, and extraction time was 8 h with a temperature of 25 °C. By examining the effect of pH, we tried to investigate the effect of the amide groups that present in MMIP and its intermolecular hydrogen interaction with folic acid. After optimising the effective parameters in polymer synthesis and adsorption rate, a magnetic imprinting dispersive solid-phase extraction method combined with fluorescence spectrophotometry at λem = 367 nm (MMIP-DSPE-FL) was constructed for sensitive determination of folic acid in tomato samples. The limit of quantification (LOQ) and limit of detection (LOD) values were 30.00 ± 0.01 μg L−1 and 10.00 ± 0.03 μg L−1, respectively, after the MMIP-DSPE preconcentration. Three tomato samples were analysed to give recoveries in the range of 80.2–81.6%, with relative standard deviation values below 0.6% (n = 3). The prepared MMIP-DSPE showed high selectivity toward folic acid, which could be used six times without changing adsorption capacity. The adsorption isotherm of the folic acid-imprinted polymer pursued the Langmuir model (RL = 0.029), and the kinetics model followed pseudo-first-order (R 2 = 0.9974).

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Abstract

The work was carried out to explore whether the anti-inflammatory effect of n-3 unsaturated fatty acids on patients with rheumatoid arthritis is related to the levels of inflammatory markers CRP and ESR. Studies on the treatment of rheumatoid arthritis with n-3 unsaturated fatty acid diet therapy and the outcome index containing CRP and/or ESR were included, and studies on the subjects suffering from other diseases affecting the outcome index were excluded. PubMed, Web of Science, EMBASE and Google Scholar were systematically searched, and all studies published from the establishment of the library to 2024 were collected. The Cochrane Bias Risk Assessment tool was used to evaluate the quality of the included studies. Data analysis was performed using Stata 16.0 software. Seven studies were included in this analysis. A total of 399 subjects were studied to explore the effect of an n-3 unsaturated fatty acid diet on rheumatoid arthritis. The results showed that there was no significant difference in CRP (Hedges's g = 0.06, 95% CI: −0.48–0.37, P = 0.79) and ESR (Hedges's g = −0.14, 95% CI: −0.61–0.33, P = 0.55) between the intervention and control groups. The results of this study showed that the anti-inflammatory effect of unsaturated fatty acids on rheumatoid arthritis was not correlated with CRP and ESR levels. Due to the small number of included studies, more high-quality studies are still needed to confirm this.

Open access