Staphylococcal enterotoxins are metabolic products of Staphylococcus aureus that are responsible for the second-most-commonly reported type of food poisoning. Polyphenols are known to interact with proteins to form complexes, the properties of which depend on the structures of both the polyphenols and the protein. In the present study, we investigated the binding of four flavonoid polyphenols to Staphylococcal enterotoxin B (SEB) at pH 7.5 and 25 °C: (-)-epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC), kaempferol-3-glucoside (KAM-G) and kaempferol (KAM). Fluorescence emission spectrometry and molecular docking were applied to compare experimentally determined binding parameters with molecular modeling. EGCG showed an order of magnitude higher binding constant (1.4 × 105 M−1) than the other studied polyphenols. Our blind-docking results showed that EGCG and similar polyphenolic ligands is likely to bind to the channel at the surface of SEB that is responsible for the recognition of the T-cell beta chain fragment and influence the adhesion of SEB to T cells.
COBISS.SI-ID: 4417400
In our present paper, we investigate the structural and dynamic properties of archaeal lipid bilayer which compose membranes of Aeropyrum pernix at two different temperatues. The bilayers were first analyzed using Small-Angle X-Ray Scattering (SAXS), which give us the electron density profiles. They were compared to the electron density profiles derived from MD simulations. The MD simulations showed how the molecules and their moieties are distributed and orientated in the membrane. The extended study (Electroporation of Archaeal Lipid Membranes) of these lipids was already published.
COBISS.SI-ID: 1752879
Anthocyanins are the largest group of water-soluble pigments in the plant kingdom. As with other polyphenols, they express antioxidant activity in vivo. Anthocyanins are associated with reduced risk of some several diseases, such as atherosclerosis and diabetes. Their beneficial health effects depend on the efficiency of their absorption. The intake of anthocyanins from the gastrointestinal lumen into the blood is likely to occur through the epithelium of the stomach, intestine and colon. The mechanisms of absorption differ from site to site, and they depend on the structure of the molecules that are absorbed. In plasma, anthocyanins can be found in their intact form, or as the corresponding phenolic acids and aldehydes, and also as methyl, sulfate and glucuronyl conjugates. Although aglycones can exist in plasma for short times, they are prone to degrade due to their instability; however, binding with proteins might preserve their intact structures. The plasma concentrations of anthocyanins are low, and efficient transport is crucial for their accessibility to tissues. Anthocyanins can cross the blood-brain barrier. However, besides their reduction of oxidative stress, the mechanisms behind their influence on neuronal activity are not completely understood. In this mini-review, we provide a short overview of the bioavailability, metabolic products, and transport processes of anthocyanins.
COBISS.SI-ID: 4332920
The aim of this work is to investigate the effect of electrostatic interactions between the nanoparticles and the membrane lipids on altering the physical properties of the liposomal membrane such as fluidity and bending elasticity. For this purpose, we have used nanoparticles and lipids with different sur- face charges. Positively charged iron oxide (γ − Fe2O3) nanoparticles, neutral and negatively charged cobalt ferrite (CoFe2O4) nanoparticles were encap- sulated in neutral lipid 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine and negatively charged 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine lipid mixture. Membrane fluidity was assessed through the anisotropy measure- ments using the fluorescent probe 1,6-diphenyl-1,3,5-hexatriene. Though the interaction of both the types of nanoparticles reduced the membrane fluidity, the results were more pronounced in the negatively charged liposomesencapsulated with positively charged iron oxide nanoparticles due to strong electrostatic attractions. X-ray photoelectron spectroscopy results also con- firmed the presence of significant quantity of positively charged iron oxide nanoparticles in negatively charged liposomes. The experimental results were supported by the simulation studies using modified Langevin-Poisson-Boltzmann model.
COBISS.SI-ID: 4329848
In this review being published in scientific journal “Comprehensive reviews in food science and food safety” we are focused on sinapic acid. Sinapic acid is widespread secondary metabolite in the plant kingdom (fruits, vegetables, cereal grains, oilseed crops, and some spices and medicinal plants) and as such is common in the human diet. Derivatives of sinapic acid are characteristic compounds in the Brassicaceae family. This review summarizes the results of investigations that show on antioxidant, antimicrobial, anti-inflammatory, anticancer, and anti-anxiety activity of sinapic acid. 4-Vinylsyringol (a decarboxylation product of sinapic acid) is a potent antioxidative and antimutagenic agent which suppresses carcinogenesis and the induction of inflammatory cytokines. Sinapine (sinapoyl choline) is considered to be an acetylcholinesterase inhibitor which might have therapeutic applications in various disease treatments. Mainly due to their antioxidative activity, these compounds have been suggested for potential use in food processing, cosmetics, and the pharmaceutical industry, and this review aims to summarize current knowledge on the natural sources, chemistry, and biological activity of these substances.
COBISS.SI-ID: 4286840