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Abstract

This study validated the performance of the reverse transcriptase‐polymerase chain reaction (rRT-PCR) based Cepheid Xpert® Xpress SARS-CoV-2 assay against the TIB MOLBIOL E-gene/EAV, a standard laboratory rRT-PCR SARS-CoV-2 assay. Upper and lower respiratory tract samples (nasopharyngeal and nasal swabs, bronchoalveolar lavage, and tracheal aspirate) were obtained from patients suspected to have contracted COVID-19. Results from the Xpert® Xpress and standard rRT-PCR assays were compared for positive and negative agreement and analyzed for precision, reproducibility, 95% confidence intervals, and coefficients of variation. The Xpert® Xpress assay demonstrated 100% agreement with the standard lab rRT-PCR for both upper and lower respiratory tract samples. Both the Xpert® Xpress and lab rRT-CPR identified weakly positive (Ct values 35–39) sample replicates with 100% reproducibility and showed 100% precision in identifying triplicates of upper respiratory tract samples. The single-cartridge Xpert® Xpress system has a short turnaround time and can be employed to improve patient management and hospital bed allocation. Further verification of the system is required before implementation and consideration must be paid to its higher cost and impracticality for high-throughput use.

Open access

Soil science, a relatively young field of research with a history of fewer than two centuries, experienced an exponential expansion in scientific output in the last decades. While the output of all sub-disciplines is growing, research efforts in these sub-disciplines differ, reflecting the importance of the subjects. The broadening focus of soil science can be detected by the content of the increasing number and diverting thematic sessions of the World Soil Science Congresses, which are held every four years since the beginning of the 20th century. The structure of the current world congress is supposed to reflect the contemporary understanding of the internal structure of soil science, including its subdivision by major themes. Considering these soil themes/sub-disciplines, we assessed the evolution of soil science in the last three decades using scientific publications as indicators. Furthermore, we evaluated the inter-linkages of soil topics within soil research using network analysis and assessed the contribution of science to the broader fields of studies, from agriculture to engineering and environmental sciences. Results show that scientific interest towards all sub-disciplines is exploding, but environment-related topics, including subjects related to climate and contamination, show an even sharper increase. As far as the internal structure of soil science is concerned, research efforts are organised around the major topics of microbiology, soil contamination, nutrients, soil physics and water management. Our study reveals that currently the highest interest towards soil is coming from ecology and environmental sciences, followed by agriculture, engineering, geology and plant sciences, respectively.

Open access
Acta Alimentaria
Authors:
N. Kellner
,
E. Antal
,
A. Szabó
, and
R. Matolcsi

Abstract

Guignardia bidwellii, indigenous to North America, is a significant pathogen of grapes long known in Hungary, infecting only the growing green parts of the vine (leaves, petioles, shoots, and bunches). In the absence of adequate plant protection and extreme weather conditions such as a predominantly humid, warm year, black rot of grapes can be expected. The pathogen can cause high yield losses due to grape rot and reduce wine quality if the infection is severe.

The evolution of certain biogenic amine compounds were investigated under the influence of grape black rot. The results obtained showed that they were present in low concentrations from an oenological point of view. Polyphenol composition was consistent with the literature, blackening affected mainly the concentration of catechin. Black rot fungus does not produce β-glucosidase enzyme. In terms of resveratrol content, black rot has no particular effect. However, like Botrytis cinerea, it produces glycerol and, proportionally, gluconic acid in lower concentrations.

It can be concluded that black rot of grapes does not cause health problems when introduced into wine processing.

Open access
Progress in Agricultural Engineering Sciences
Authors:
József Mihalkó
,
Dóra Szepesi-Bencsik
,
Gabriella Zsarnóczay
, and
László Ferenc Friedrich

Abstract

Animal food, especially meat, has played an important role in the history of mankind. Different meats can be used in the production of meat products. In addition to lean meats, mechanically deboned meat (MDM) and mechanically separated meat (MSM) can also be used in meat products. However, the latter does not qualify as meat due to damage to the muscular structure due to the high pressure applied during the separation, therefore cannot be included in the meat content of products.

The aim of our experiment was to compare whole, minced meat, MDM and MSM from turkey (raw and in the form of meat paste). Technofunctional tests (water-holding and -binding capacity), color measurement, chemical composition (moisture, protein and fat content), electron microscopic recording, rheological properties show that the quality of MSM is inferior to other meat raw materials. These properties can also result in the production of lower quality products.

Open access

Abstract

Transcription factors of the nuclear factor kappa‐light‐chain‐enhancer of activated B cells (NF-ĸB) family control important signaling pathways in the regulation of the host innate immune system. Various bacterial pathogens in the human gastrointestinal tract induce NF-ĸB activity and provoke pro-inflammatory signaling events in infected epithelial cells. NF-ĸB activation requires the phosphorylation-dependent proteolysis of inhibitor of ĸB (IĸB) molecules including the NF-ĸB precursors through ubiquitin-mediated proteolysis. The canonical NF-ĸB pathway merges on IĸB kinases (IKKs), which are required for signal transduction. Using CRISPR-Cas9 technology, secreted embryonic alkaline phosphatase (SEAP) reporter assays and cytokine enzyme-linked immunosorbent assay (ELISA), we demonstrate that the actin-binding protein cortactin is involved in NF-ĸB activation and subsequent interleukin-8 (IL-8) production upon infection by Helicobacter pylori, Salmonella enterica and Pseudomonas aeruginosa. Our data indicate that cortactin is needed to efficiently activate the c-Sarcoma (Src) kinase, which can positively stimulate NF-ĸB during infection. In contrast, cortactin is not involved in activation of NF-ĸB and IL-8 expression upon infection with Campylobacter species C. jejuni, C. coli or C. consisus, suggesting that Campylobacter species pluralis (spp.) induce a different signaling pathway upstream of cortactin to trigger the innate immune response.

Open access

Abstract

Despite vaccine availability, the global spread of COVID-19 continues, largely facilitated by emerging SARS-CoV-2 mutations. Our earlier research documented that a specific combination of plant-derived compounds can inhibit SARS-CoV-2 binding to its ACE2 receptor and controlling key cellular mechanisms of viral infectivity. In this study, we evaluated the efficacy of a defined mixture of plant extracts and micronutrients against original SARS-CoV-2 and its Alpha, Beta, Gamma, Delta, Kappa, and Mu variants. The composition containing vitamin C, N-acetylcysteine, resveratrol, theaflavin, curcumin, quercetin, naringenin, baicalin, and broccoli extract demonstrated a highest efficacy by inhibiting the receptor-binding domain (RBD) binding of SARS-CoV-2 to its cellular ACE2 receptor by 90%. In vitro exposure of test pseudo-typed variants to this formula for 1 h before or simultaneously administrated to human pulmonary cells resulted in up to 60% inhibition in their cellular entry. Additionally, this composition significantly inhibited other cellular mechanisms of viral infectivity, including the activity of viral RdRp, furin, and cathepsin L. These findings demonstrate the efficacy of natural compounds against SARS-CoV-2 including its mutated forms through pleiotropic mechanisms. Our results imply that simultaneous inhibition of multiple mechanisms of viral infection of host cells could be an effective strategy to prevent SARS-CoV-2 infection.

Open access

Abstract

A number of methods have been applied to measure total antioxidant capacity (TAC), including FRAP, which is based on reducing the amount of iron ions in a complex compound. Researchers often use measurement of absorbance 10 min after mixing a sample with the FRAP reaction solution to calculate TAC. The FRAP solution has been shown to alter absorbance over time by ca 0.0010–0.0020 per hour, under storage conditions. This article intends to show that some substances do not fully or sufficiently react within the common analysis period. It is evident from the results that some substances react more quickly and others very slowly. Absorbance in relation to various phenols was measured. Compared to the levels of absorbance at 10 min, mean absorbance at 48 h was higher by 5,395% for vanillin, 426% for caffeic acid, 170% for sinapinic acid, 67% for gallic acid, 19% for syringic acid, and only by 4% for Trolox. Results for vanillin and caffeic acid indicate potential auto-catalysis.

Open access

Abstract

Hungarian fruit vinegars were characterised in terms of physicochemical attributes (total polyphenol content, antioxidant characteristics/FRAP, CUPRAC, ABTS/, ascorbic acid content, pH, total soluble solids), sensory profiles, and antimicrobial properties.

Both compositional and sensory profiles showed distinct patterns depending on the type of vinegar (Tokaj wine, balsamic or apple) and the additional fruit used. Balsamic vinegars maturated on rosehip, sea buckthorn, and raspberry showed outstanding antioxidant performances. Rosehip, raspberry, and quince vinegars, as well as vinegars produced from Tokaji aszú and balsamic apple obtained high scores for fruity and sweet notes.

Antimicrobial activities were tested on Gram-negative and Gram-positive organisms, including probiotic bacteria. Generally, only weak activities were obtained, which was attributed to the natural sugar content of the samples, depending on the type of the vinegar and the fruit. Similar results, but more pronounced bacterial growth inhibitions were obtained for probiotic strains, however, some probiotic strains were resistant to at least two of the vinegars. Based on these, balsamic apple, raspberry, rosehip, quince, and sea buckthorn may qualify as potential functional components of probiotic preparations containing some of the strains tested.

Open access

Abstract

Aroma components of wines play an important role in the sensory quality of wines. In our paper we investigate the effect of commercially available yeast nutrients under different fermentation parameters. Caproic acid, caprylic acid, capric acid, and different fatty acid esters were used as markers of the alcoholic fermentation process. The optimal temperature for the fermentation of different white wines was at 15–16 °C, in the case of examined wines lower concentrations of fatty acids and fatty acid esters were found at this temperature. At 25–26 °C fermentation temperature very high concentrations of fatty acids and fatty acid esters were detected. Applying different nitrogen-containing wine additives we managed to achieve better aroma profiles for white wines even using musts of lower quality.

Open access

Abstract

The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RSCB PDB) provides a wide range of digital data regarding biology and biomedicine. This huge internet resource involves a wide range of important biological data, obtained from experiments around the globe by different scientists. The Worldwide Protein Data Bank (wwPDB) represents a brilliant collection of 3D structure data associated with important and vital biomolecules including nucleic acids (RNAs and DNAs) and proteins. Moreover, this database accumulates knowledge regarding function and evolution of biomacromolecules which supports different disciplines such as biotechnology. 3D structure, functional characteristics and phylogenetic properties of biomacromolecules give a deep understanding of the biomolecules’ characteristics. An important advantage of the wwPDB database is the data updating time, which is done every week. This updating process helps users to have the newest data and information for their projects. The data and information in wwPDB can be a great support to have an accurate imagination and illustrations of the biomacromolecules in biotechnology. As demonstrated by the SARS-CoV-2 pandemic, rapidly reliable and accessible biological data for microbiology, immunology, vaccinology, and drug development are critical to address many healthcare-related challenges that are facing humanity. The aim of this paper is to introduce the readers to wwPDB, and to highlight the importance of this database in biotechnology, with the expectation that the number of scientists interested in the utilization of Protein Data Bank’s resources will increase substantially in the coming years.

Open access