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Abstract
Listeria monocytogenes is able to form biofilms on food contact surfaces. Effectiveness of salt concentration, pH, and temperature on the formation of L. monocytogenes biofilms was evaluated individually and in combinations using microtiter plate assay by measuring the optical density. The tested strains differed in their biofilm formation (low, moderate, and strong) ability. At 37 °C, decreasing amounts of biofilms was observed in almost all L. monocytogenes strains when the NaCl concentration increased from 0.05 to 15%, but all strains were able to form biofilm even at 1 °C. There was no significant difference in biofilm formation between pH 4, 5, and 6, except for some strains. When stress conditions were tested in combination, the addition of 15% NaCl significantly inhibited the growth of L. monocytogenes at 1 °C and 4 °C, and the weak biofilm-forming strains were less sensitive to the temperature and to NaCl treatments than the strong biofilm-forming strains. These results enhance our knowledge of the application of NaCl, temperature, and pH stresses in the food industry and provide basis to develop new strategies for control of biofilm formation of this pathogen.
Az azbesztszálak kimutatására szolgáló vizsgálatok középpontjában a levegőszennyezettségi értékek álltak, de a 21. században felmerült az igény a problémakör kiterjesztésére. Az elmúlt években megjelent nemzetközi tudományos szakirodalmak megcáfolták az évtizedeken át fennálló feltételezést, miszerint az azbeszt csupán a levegőterheltség révén vált ki kockázatot. Vízminőségi és talajminőségi kutatások által teret nyert az azbesztszálak, különösen a krizotilszálak alternatív transzportútjainak vizsgálatát célzó kutatásterület. Annak ellenére, hogy mind a települési, mind pedig a mezőgazdasági vízgazdálkodás potenciálisan érintett a krizotil-azbeszt jelenléte kapcsán, nincs nemzetközi szinten egységes és elfogadott módszer vagy küszöbérték az egyes vízforrások biztonságára vonatkozóan. A kutatások nyilvánvaló korlátja, hogy csekély mennyiségű és minőségű tudás érhető el. Az azbesztszálak megjelenése az egyes vízbázisokban jelentősen megváltoztatja mind a mezőgazdasági, mind a települési vízgazdálkodás környezeti hatásoknak való kitettségéről alkotott eddigi ismereteinket. Az öntözővizzel és a gyűjtött csapadékkal kijuttatott azbesztszálak hatásainak palettája mára túlhaladta a humán- és állategészségügyi hatásokat, immár figyelmet kell fordítani a vegetációs hatásokra is. Annak érdekében, hogy nagyobb betekintést nyerjünk az azbeszttoxicitás növényekre gyakorolt hatásaiba, sokkal több tudományos eredményre van szükség.
Jelen összefoglaló tanulmányban bemutatjuk az azbeszt, különös tekintettel a krizotil azbeszt legfontosabb tulajdonságait, humán-, állat- és növényegészségügyi kockázatait. Rávilágítunk arra, hogy ismereteink rendkívül hiányosak, valamint felhívjuk a figyelmet a települési és mezőgazdasági vízgazdálkodás érintettségének egyes faktoraira, közvetlen és közvetett kockázati tényezőire, valamint arra, hogy ezek miként hatnak az élőlényekre, kiemelt tekintettel a növényekre.
Abstract
For a long time, olive oil has been considered for formulation of biopharmaceuticals and received a prestigious place in cuisine for its unique organoleptic and nutritional properties. Nevertheless, oxidation of fatty acids in olive oil provides short shelf-life and undesirable organoleptic properties. Thus, microencapsulation of olive oil is a considerable promising approach to maintain its quality and biological activities. The objective of this investigation was to prepare extra virgin olive oil microcapsule by sequential technologies, such as water emulsification of olive oil with wall material (matrix) and freeze drying of emulsion. The effect of wall material composition was examined to prepare microcapsule of extra virgin olive oil. Different ratios of wall materials such as maltodextrin (MD), carboxymethyl cellulose (CMC), and gum arabic (GA) were used. Furthermore, effects of emulsification technologies, such as homogenisation with rotor–stator homogeniser (RSH) and cross-flow membrane emulsification (CFME) were investigated. The stability of emulsion was higher when emulsion was prepared by RSH; however, the droplet mean diameter (D32) was lower in case of RSH compared to CFME. The highest encapsulation efficiency (EE) was found as 68.96 ± 2.6% when CFME was adopted and composition of wall materials was 15 g MD, 15 g GA, and 5 g CMC.
Abstract
Rye is an important raw material of bread due to tradition and its favourable nutritional and technological qualities. Despite the beneficial fibre composition, a special group of short-chain carbohydrates, the so called FODMAPs (fermentable oligo-, di-, monosaccharides and polyols) may cause problems for patients with irritable bowel syndrome. The aim of our work was to investigate the non-starch carbohydrate (dietary fibre compounds, short-chain carbohydrates) composition of rye varieties, and of their novel milling fractions obtained from industrial milling trials and test loaves made from them. Regarding fibre and short chain carbohydrate composition, rye varieties did not show significant differences. In new subfractions, fibre and FODMAP composition were described, among profiles most of them differ from commonly used flours, independently from variety. The yeast fermentation and baking caused a decrease in water-extractable arabinoxylan content, at the same time increased the substitution pattern of water-extractable arabinoxylans. Furthermore, breadmaking process decreased the fructan content, and therefore increased the fructose level, thus modifying the short-chain carbohydrate composition. Based on our knowledge, this research is among the first ones investigating the fibre and short-chain composition of rye from the seeds to the consumable final products.
Abstract
The rapid technological development that is still taking place today, with increasingly interconnected IT tools, is introducing dramatic changes. The development of computer programs is rapidly transforming traditional processes and the systems that support them. It is therefore natural that the fourth industrial revolution (Industry 4.0) and its impact on Hungarian companies is one of the key topics of our time. We conducted an exploratory quantitative survey, asking 140 managers of Hungarian small, medium and large enterprises about their current situation in the context of Industry 4.0. We sought to find out to what extent the specific R&D and innovation potential of Industry 4.0 is accepted, and whether it has already been introduced in the companies. On a qualitative side, 2 case studies and 3 interviews were conducted, in which structured interviews were used to further explore the issue. We aimed to find out where SMEs stood in terms of digital preparedness and what advantages, possible disadvantages, and goals they managed to identify. Our research showed that an increasing number of companies have already decided to take the first steps towards industrial digitalisation, which will completely transform their internal processes.
Abstract
In the present study, antibiotic resistance profiles and biofilm forming abilities of 9 Listeria monocytogenes isolates obtained from out of 30 retail meat samples were determined, and the effect of commercial white vinegar on these virulence factors in isolates exposed to subMIC concentrations were investigated. All isolates were found to be resistant to cefotixin and oxacillin, 8 isolates (26.6%) to clindamycin, 1 isolate (3.3%) to rifampicin, and 1 (3.3%) isolate was found to show intermediate resistance against clindamycin. Biofilm formation was determined for all the isolates at 22 °C and 37 °C (24 h, 48 h and 72 h). MIC values of white vinegar samples were determined at 3.12% for all isolates. MIC/2 and MIC/4 concentrations of white vinegar increased the biofilm forming capacity of the isolates by 21.2% and 17.1%, respectively. After exposure to MIC/2 concentration of white vinegar for seven days, the antibiotic resistance status of the isolates to tetracycline, rifampicin, and clindamycin changed, and the biofilm forming abilities significantly decreased at 4 °C and 37 °C for 48 h and at 37 °C for 72 h (P < 0.05). The results showed that the use of subMIC concentrations of white vinegar should be avoided in routine sanitation applications.
Abstract
The aims of the present study were to detect Escherichia coli in chicken distributed in Birjand, to investigate the prevalence of ESBL and AmpC beta-lactamases producers among them, and to identify their antibiotic resistance patterns. The study was conducted on 150 chicken samples, and the antimicrobial susceptibility patterns were determined by the Kirby–Bauer disk diffusion method. Phenotypic identification of ESBL and AmpC was performed by the combined disk test (CDT). The specific genes of ESBL and AmpC beta-lactamases were detected using two multiplex PCR (m-PCR) assays. According to our results, 116 out of 150 chicken samples were contaminated with E. coli. Moreover, the highest resistance of E. coli isolates was observed to trimethoprim/sulfamethoxazole (46%), ampicillin (40%), and amoxicillin (29.33%). In the molecular confirmation step, among 17 (11.33%) beta-lactamase producers, five samples contained the bla CTX-M14 gene (3.33%), two samples contained bla DHA (1.33%) and bla CTX-M3 gene (1.33%), and just one sample carried bla CMY-2 gene (0.66%). The bla SHV and bla TEM genes were not detected in any strains isolated from the chicken samples. This study showed the contamination of chicken with antibiotic-resistant E. coli. Therefore, it is recommended that veterinarians be more precautious in prescribing antibiotics.
Abstract
Intermittent fasting (IF) is a dietary strategy that involves alternating periods of abstention from calorie consumption with periods of ad libitum food intake and has been shown to have beneficial effects in many ways. Recent studies have shown that IF attenuates neurodegeneration and improves cognitive decline, enhances functional recovery after stroke as well as attenuates the pathological and clinical features of epilepsy in animal models. Furthermore, IF induced several molecular and cellular adaptations in neurons that overall enhanced cellular stress resistance, synaptic plasticity, and neurogenesis. In this review, the beneficial effects of IF on central neurological disorders are discussed. The information summarised in this review can be used to help contextualise existing research and better guide the development of future IF interventions.
Abstract
Nattokinase (NK) is effective in the prevention and treatment of cardiovascular disease. Cucumber is rich in nutrients with low sugar content and is safe for consumption. The aim of this study was to construct a therapeutic cucumber that can express NK, which can prevent and alleviate cardiovascular diseases by consumption. Because the Bitter fruit (Bt) gene contributes to bitter taste but has no obvious effect on the growth and development of cucumber, so the NK-producing cucumber was constructed by replacing the Bt gene with NK by using CRISPR/Cas9. The pZHY988-Cas9-sgRNA and pX6-LHA-U6-NK-T-RHA vectors were constructed and transformed into Agrobacterium tumefaciens EHA105, which was transformed into cucumber by floral dip method. The crude extract of NK-producing cucumber had significant thrombolytic activity in vitro. In addition, treatment with the crude extract significantly delayed thrombus tail appearance, and the thrombin time of mice was much longer than that of normal mice. The degrees of coagulation and blood viscosity as well as hemorheological properties improved significantly after crude extract treatment. These findings show that NK-producing cucumber can effectively alleviate thrombosis and improve blood biochemical parameters, providing a new direction for diet therapy against cardiovascular diseases.
Abstract
Proper gluten quantitation is essential for providing safe gluten-free food for patients living with celiac disease (CD). However, gluten quantitation faces several challenges: the lack of a reference method and certified reference materials, the variability of methods and the effects of genetic and environmental factors on gluten. Among all these challenges our research group focuses on gluten reference material development. Gluten content is determined by enzyme linked immunosorbent assay (ELISA) methods to obtain comparable data for the selection of cultivars used in our reference material development efforts. As ELISA methods are developed for determining low gluten concentrations, application for these special research purposes requires a 10,000-fold dilution. The formerly performed process was a post-extraction liquid dilution that proved to be sufficient for wheat samples. However, gluten contents of rye and barley samples were found to be overestimated by ELISA methods. One of the suggested reasons is the structural and solubility changes of gluten proteins during the dilution process. Therefore, our present study focuses on the comparison of the original dilution method and a revised version using solid-phase dilution in a gluten-free matrix.
