Search results for "bacteria."

Modification of face masks with zeolite imidazolate framework-8

2022

The worldwide spread of the SARS-CoV-2 virus has continued to accelerate, putting a considerable burden on public health, safety, and the global economy. Taking into consideration that the main route of virus transmission is via respiratory particles, the face mask represents a simple and efficient barrier between potentially infected and healthy individuals, thus reducing transmissibility per contact by reducing transmission of infected respiratory particles. However, long-term usage of a face mask leads to the accumulation of significant amounts of different pathogens and viruses onto the surface of the mask and can result in dangerous bacterial and viral co-infections. Zeolite imidazolat…

Antioxidative and Photo-Induced Effects of Different Types of N-Doped Graphene Quantum Dots.

2022

Due to the increasing number of bacterial infections and the development of resistivity toward antibiotics, new materials and approaches for treatments must be urgently developed. The production of new materials should be ecologically friendly considering overall pollution with chemicals and economically acceptable and accessible to the wide population. Thus, the possibility of using biocompatible graphene quantum dots (GQDs) as an agent in photodynamic therapy was studied. First, dots were obtained using electrochemical cutting of graphite. In only one synthetic step using gamma irradiation, GQDs were doped with N atoms without any reagent. Obtained dots showed blue photoluminescence, with…

A novel TiO2-assisted magnetic nanoparticle separator for treatment and inactivation of bacterial contaminants in aquatic systems

2014

Ferromagnetic nanoparticles (Fe-nanoparticles) have been functionalized with recombinant poly- Glu [glutamic acid]-tagged silicatein, a biomineral-synthesizing enzyme from siliceous sponges that forms the inorganic silica skeleton of those animals. The biocatalytic activity of silicatein was used to form a titania (TiO2) shell around the iron nanoparticle core, using the water-soluble non- natural substrate titanium bis(ammonium lactato)-dihydroxide (TiBALDH). Thereby the diameter of the nanoparticles increases from 7 nm to ≈22 nm. This procedure also allows the layer-by-layer fabrication of titania/silica- Fe-nanoparticles. SEM/EDX analysis confirmed the presence of the Ti and Si signals i…

Synergistic enhancement via plasmonic nanoplate-bacteria-nanorod supercrystals for highly efficient SERS sensing of food-borne bacteria

2017

Bio-sensing techniques utilizing metallic nanoparticles as a probe have gained more and more attention and play today an important role in the detection of bacteria. To date, although several sensing materials have been tested, there is still a long way to go to achieve a fast, low-cost, ultrasensitive and multifunctional substrate suitable for a universal biosensor for detection of bacterial cells. Here, we report a novel probe design based on anisotropic plasmonic nanoparticles organized to a biocompatible 3D bio-inorganic scaffold, i.e., nanoplate-bacteria-nanorod supercrystals (NBNS) with extremely high surface-enhanced Raman spectroscopic (SERS) activity as a model of synergistic plasm…

Biomineralization events in Recent volcanic and sedimentary settings: textural features and isotope signatures.

2008

Planktivorous vendace (Coregonus albula) utilise algae-derived fatty acids for biomass increase and lipid deposition

2018

Spatial and seasonal variation in the abundance and composition of phytoplankton and other basal resources (bacteria, terrestrial detritus) influence the availability of essen-tial polyunsaturated fatty acids (PUFA) for upper trophic levels in lake food webs. We studied accumulation, composition and content of fatty acids in planktivorous ven-dace (Coregonus albula) muscle tissue during the summer feeding period (May to late September) in six boreal lakes. Vendace muscle fatty acid content increased from ~17.7 mg/g DW to ~28.1 mg/g DW from spring to summer, corresponding to a ~59% increase in total fatty acids. PUFA accounted for 45%–65% of all fatty acids, and the most abundant fatty acid …

Preliminary results for application of culture-independent molecular methods to olive brines bacterial communities.

2006

Transformation of green table olives requires a brining stage during which olives ferment. In naturally transformed olives, both flavour improvement and debittering are associated to fermentation. Because of brine features, naturally occurring bacteria and yeasts are progressively selected by the high salt concentration, low pH and phenolic compounds with antimicrobial activity. The establishment of an adequate fermenting microflora is essential to obtain a good and safe product; then, during transformation, control of chemical and microbiological parameters is crucial. Currently, microflora is periodically monitored by plate-counting of main groups. These routine analyses, however, don’t s…

Influence of citrates nanoparticles on morphological traits of bacterial cells pseudomonas syringae pv. atrofaciens

2020

Electron microscope investigations have revealed disintegration of the cell wall of Pseudomonas syringae pv. atrofaciens and subsequent killing of bacterial cells after application of 1% solutions of the citrates of Ag-Cu nanoparticles, the complex Co-Cu-Zn-Fe-Mn-Mo-Mg (Avatar-1) and iodine-selenium. In field conditions, it was revealed that pre-sowing treatment of wheat seeds with the aforementioned 1% solutions significantly inhibited the development of basal glume rot in cereals with artificial infection of Pseudomonas syringae рv. аtrofaciens. Consequently, reduction of the typical symptoms of basal glume rot of cereals and the percentage of isolated cells of Pseudomonas syringae рv. аt…

Identification of phytopathogenic bacteria in maize seeds in Ukraine

2018

The main bacterial diseases of maize: bacterial wilt of maize (Pantoea stewartii subsp. stewartii), goss’s bacterial wilt (Clavibacter michiganensis subsp. nebraskensis), seed rot-seedling blight of maize (Bacillus subtilis), bacterial spot of maize (Pseudomonas syringae pv. syringae), bacterial leaf spot of maize (Pantoea agglomerans) and bacterial stalk rot of maize caused by several causative agents, were described. The causative agents of these diseases are often stored and transmitted with seeds, so seed analysis for the presence of phytopathogenic bacteria is an important step in the pathogen control system. For analysis, the corn seeds that were grown in the Poltava and Kiev regions …

Stochastic model for a biological complex system: analysis of the bacterial growth in food products

2012

The Physics of Complex Systems has recently taken a more and more important role in the description of natural systems because of the interactions, both deterministic and noisy, between such systems and the environment. In particular the noise plays a relevant role in biological systems, whose dynamics is strongly influenced by environmental variables subject to random fluctuations. In this work a stochastic model is exploited to reproduce the growth of bacteria in food of animal origin. Specifically the dynamics of a bacterial species, Listeria monocytogenes, is analyzed in the presence of lactic acid bacteria (LAB) during the period of the fermentation of meat products. The model, based o…