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Abstract
Infections caused by Staphylococcus aureus are currently a worldwide threat affecting millions of individuals. The pathogenicity of S. aureus is associated with numerous virulence factors, including cell surface proteins, polysaccharides, and secreted toxins. The pore-forming α-hemolysin, known as α-toxin, is produced by nearly all virulent strains of S. aureus and is implicated in several diseases including skin and soft tissue infections, atopic dermatitis, and pneumonia. There are currently no vaccines available for the prevention of S. aureus infections and the efficacy of available antibiotics has been fading. In this study we examined the mode of antihemolytic activity of theaflavin-3,3′-digallate against α-hemolysin of methicillin-resistant S. aureus by molecular docking using AutoDock Vina as the molecular docking tool. The theaflavin-3,3′-digallate docked the molecular sequence of the Hla (PDB ID:7ahl). The scores of the top 10 binding modes obtained were between −9.0 and −8.5 kcal mol−1, and the best binding mode was −9.0 kcal mol−1. Direct binding sites of theaflavin-3,3′-digallate to the “stem” domain of Hla were revealed which primarily targeted of the residues Met113, Thr117, Asn139. The disclosure of this potential binding mode warrants further clinical evaluation of theaflavin-3,3′-digallate as an anti-hemolytic compound in order to practically validate our results.
Abstract
Potato mulching practices and their effects often differ, and the results are sometimes contradictory in the literature, as they vary depending on climatic conditions and growing practices. In this study, we analysed 68 peer-reviewed publications to reveal which problems of potato cultivation were intended to be solved by mulching with organic materials. We have found that the main goals of mulching are the preservation of soil moisture, the reduction of soil temperature, and the suppression of weeds, in which mulching provides effective help. In different parts of the world, different organic mulches increased the yield of potatoes in 78% of the studies. Although the occurrence and damage of pests, pathogens and weeds are extremely understudied (16, 18, 29% of the studies), we can conclude that organic mulches effectively reduced their damage.
Abstract
Effect of edible coatings based on zedo gum (ZG) containing thyme (Thymus vulgaris) essential oil (TEO) and cinnamon (Cinnamomum verum) extract (CAE) on the quality and proteolysis of cheddar cheese was investigated. Four treatments were prepared using different coating formulas including: C (coated cheese with paraffin and wax mixture as commercial coating), Z treatment (coated cheese with ZG solution), TEO treatment (coated cheese with TEO), and CAE treatment (coated cheese with CAE). The results showed that the highest moisture content and proteolysis indices were related to sample C; the lowest moisture content and number of starter lactic acid bacteria (SLAB) and the highest protein content, FDM content, proteolysis indices and number of non-starter lactic acid bacteria (NSLAB) were related to sample Z; while the TEO and CAE treatments showed similar values. Also, TEO and CAE had an inhibitory effect on growth of moulds and yeasts, without affecting NSLAB and SLAB. Therefore, instead of commercial coating, zedo gum containing T. vulgaris essential oil or C. verum extract can be used as active coating on cheddar cheese.
Abstract
In this study, we compile the findings to date on using several cellulose-based materials as adsorbents of potentially toxic elements (PTEs) from wastewater. Furthermore, this review discussed the destiny of PTEs-loaded cellulose-based adsorbents and some sustainable methods for their management, hoping to close the pollution loop.
Abstract
Wheat is a cereal of special importance in the world cereal production. Fusarium head blight is one of the most important diseases of wheat caused by phytopathogenic Fusarium species that significantly reduce wheat production. This disease reduces grain yield and quality and causes the presence of harmful mycotoxins. The purpose of this study is to test the effect of Fusarium infection on wheat quality parameters in two wheat varieties Alföld and Mv Karéj. The results showed that Fusarium infection was higher in 2021 (91.47% and 95.20%) compared to 2020 (44.33% and 40.27%) in the two wheat varieties used Alföld and Mv Karéj respectively. In Alföld, Fusarium infection had a negative effect on protein content, test weight, thousand kernel weight, gluten content and Zeleny sedimentation index, whereas falling number was not affected. In Mv Karéj, Fusarium infection had a negative effect on test weight, thousand kernel weight, falling number and Zeleny sedimentation index, whereas protein content and gluten content were not affected. Although Fusarium infection reduced wheat quality, Mv Karéj showed a stable protein and gluten content whereas Alföld showed a stable falling number. Thus, Mv Karéj is more tolerant to Fusarium infection compared to Alföld.
Abstract
The main objectives of the present study were to investigate the physical attributes and chemical characteristics of dried apple cubes. The apple cubes were dried in vacuum and infrared dryers at 40 °C and freeze dryer individually and in combination. The physical properties – texture and rehydration – of vacuum drying-assisted freeze-dried apple dices were close to the freeze-dried products. The hardness of vacuum drying-assisted freeze-dried apples was better, by at least 15.8%, than those dried by infrared-freeze, but rehydration capacities were similar. The freeze-dried control samples achieved a lower water activity (0.145) in comparison with infrared, vacuum, and combined dried ones. The infrared-freeze-dried samples retained 3.6 and 11.6% more polyphenols and antioxidant capacity than samples prepared by the other methods. The ascorbic acid content of the freeze-dried samples was significantly higher by about 59% than that of the hybrid dried samples.
Abstract
The popularity of sweet potatoes in Central Europe has been increasing recently, mainly the high-quality, perfect, fresh tubers are in demand. However, out of class grade tubers could be marketed in dried, grounded form as sweet potato flour.
The aim of this study was to characterise some important nutritional properties of flours of three sweet potato genotypes with different tuber colours (white, purple, and orange) and to investigate how this raw material affects the rheological properties of sweet potato-wheat flour blends.
Dietary fibres are present in sweet potatoes in a significant proportion, orange coloured flour showed the highest values. The main free sugars were sucrose, glucose, and fructose, but sucrose was the dominant one. Antioxidant capacity and total phenolic content also varied considerably, the purple flour had the highest values. Mineral composition showed significant variability, the purple flour contained the highest level of minerals. It was confirmed that adding sweet potato flour to wheat flour affected its rheological properties, however in a varied manner. For the orange flour these properties have lightly decreased, though it had no significant effect on dough quality, while the white and purple flours with a dosage of 5, 10 and 15% could improve the dough behaviour. Thus, sweet potato in this form is a valuable raw material.
Abstract
The aim of our research was to study the water and ethanol extractable polyphenols of stinging nettle (Urtica dioica L.) harvested in different seasons and to determine their antimicrobial activity against certain human pathogenic and food spoiling bacteria and yeasts.
Our results indicate that the spring leaf extracts had higher polyphenol contents than the root one; however, close to the end of the vegetation period these values decreased considerably in both leaves and roots. Detection and quantification of the most abundant phenolic compounds in the spring extracts by HPLC revealed the occurrence of 12 different phenol carboxylic acids and flavonoids. Flavonoid compounds were more abundant than phenol carboxylic acids in the leaves; however, their proportion was equal in the case of the roots. Nettle leaf extracts had remarkable antimicrobial activity, the spring extracts were more efficient than the autumn ones. Escherichia coli and Staphylococcus aureus were sensitive to every leaf extract, while Listeria monocytogenes and Pseudomonas aeruginosa had reduced but remarkable sensitivity patterns. Among the yeasts, Candida glabrata was strongly inhibited by the aqueous leaf extracts. Most of the strains were insensitive to the root extracts, although Enterococcus faecalis was inhibited by the root and not the leaf extracts.
Abstract
As a principal pigment in plants, chlorophyll a (Chl a) is widely used to evaluate quality changes and senescence process during storage of leafy vegetables. The determination of Chl a in plant extracts by spectrophotometric methods using various empirical equations is often unreliable. Considering the sensitivity of fluorescence detection, we report here a simple, inexpensive spectrofluorimetric method that can detect and quantify Chl a in plant extracts. The fluorescence standard used for the quantitative determination of Chl a was isolated in our laboratory from the extract of Anthrospira platensis (Spirulina). The method proved to be reliable, fast, and low cost in a study of the influence of the most commonly used domestic storage conditions on Chl a degradation in fresh-cut arugula.
Abstract
Background
Mansonellosis is a widely neglected helminth disease which is predominantly observed in tropical regions. This study was conducted to assess potential associations of the prevalence of circulating Mansonella perstans-specific cell-free DNA in human serum and HIV infection in Ghanaian individuals.
Methods
For this purpose, serum samples obtained from Ghanaian HIV-patients (n = 989) and non-HIV-infected Ghanaian control individuals (n = 91) were subjected to real-time PCR targeting the ITS-(internal transcribed spacer-)2 sequence of M. perstans and Mansonella sp. Deux.
Results
Mansonella-specific cell-free DNA was detected in serum samples of only 2 HIV-positive and 0 HIV-negative individuals, making any reliable conclusions on potential associations between HIV and mansonellosis in tropical Ghana unfeasible.
Conclusions
Future epidemiological studies on hypothetical associations between mansonellosis and HIV infections should focus more specifically on high-endemicity settings for both Mansonella spp.-infections and HIV-infections, include higher case numbers and be based on real-time PCR from whole blood rather than from serum, in which only circulating parasite DNA but no more cell-bound parasite DNA can be detected. However, the study did not show associations of HIV infections in Ghanaian individuals with Mansonella worm loads high enough to detect cell-free Mansonella DNA in serum by PCR.
