The present study aimed to evaluate acetylcholinesterase (AChE) inhibitory and antioxidant activities of Lamiaceae medicinal plants growing wild in Croatia. Using Ellman's colorimetric assay all ...tested ethanolic extracts and their hydroxycinnamic acid constituents demonstrated in vitro AChE inhibitory properties in a dose dependent manner. The extracts of Mentha x piperita, M. longifolia, Salvia officinalis, Satureja montana, Teucrium arduini, T. chamaedrys, T. montanum, T. polium and Thymus vulgaris at 1 mg/mL showed strong inhibitory activity against AChE. The antioxidant potential of the investigated Lamiaceae species was assessed by DPPH• scavenging activity and total antioxidant capacity assays, in comparison with hydroxycinnamic acids and trolox. The extracts differed greatly in their total hydroxycinnamic derivatives content, determined spectrophotometrically. Rosmarinic acid was found to be the predominant constituent in most of the investigated medicinal plants (by RP-HPLC) and had a substantial influence on their AChE inhibitory and antioxidant properties, with the exception of Teucrium species. These findings indicate that Lamiaceae species are a rich source of various natural AChE inhibitors and antioxidants that could be useful in the prevention and treatment of Alzheimer's and other related diseases.
Two decades ago, halogen bonding attracted considerable attention as a new type of non-covalent interaction and has now emerged as an important supramolecular tool for crystal engineering, ...demonstrating its ability to self-assemble low affinity entities. Specific features of halogen bonds have been subsequently harnessed in biological and material sciences to give rise to elegant functional systems with a wide range of applications. In this highlight, we focused on new concepts in polymer science, electrochemistry, electronic and sensing materials. Recent findings on the use of halogenated compounds for transmembrane transport are also discussed, together with a short summary of the current understanding of the nature of the halogen bond, in the light of modern computational tools and energy decomposition.
This review highlights recent developments of halogen bonding in materials and biological sciences with a short discussion on the nature of the interaction.
Flavonoids are widely used as phytomedicines. Here, we report on flavonoid phytomedicines with potential for development into prophylactics or therapeutics against coronavirus disease 2019 ...(COVID-19). These flavonoid-based phytomedicines include: caflanone, Equivir, hesperetin, myricetin, and Linebacker. Our in silico studies show that these flavonoid-based molecules can bind with high affinity to the spike protein, helicase, and protease sites on the ACE2 receptor used by the severe acute respiratory syndrome coronavirus 2 to infect cells and cause COVID-19. Meanwhile, in vitro studies show potential of caflanone to inhibit virus entry factors including, ABL-2, cathepsin L, cytokines (IL-1β, IL-6, IL-8, Mip-1α, TNF-α), and PI4Kiiiβ as well as AXL-2, which facilitates mother-to-fetus transmission of coronavirus. The potential for the use of smart drug delivery technologies like nanoparticle drones loaded with these phytomedicines to overcome bioavailability limitations and improve therapeutic efficacy are discussed.
•Physicochemical and Mechanical properties of chitosan-gelatin based films containing Quercetin-starch (Q) were investigated.•Quercetin-starch improved antioxidant property as well as antibacterial ...property.•Ch-ge-Q films protected foods from UV radiation.•Quercetin-starch improved mechanical properties of the film as well as WVP.
Ecofriendly chitosan-gelatin (Ch-ge) bio-composite films containing Quercetin-starch (Q) were synthesized using solution casting method. Physicochemical characteristics and mechanical properties of the resulting chitosan-gelatin containing Quercetin-starch films (Ch-ge-Q) were studied using UV, FTIR, XRD and SEM techniques. The films were also investigated for their swelling, water-vapor permeability (WVP), water solubility properties. The FTIR spectra confirmed the chemical interactions between the chitosan-gelatin and Q. Surface morphology of prepared film was analyzed by the SEM imaging while XRD spectra suggest the expanded crystallinity of the film with the addition of Q. The film also showed enhanced barrier property against UV rays. The reduction of water-vapor permeability and increase in tensile strength while a decrease in elongation at break has been observed in the Ch-ge-Q film compared to Ch-ge film. The antibacterial activity of Ch-ge-Q film against both gram positive (B. substilis) and gram negative (E. coli) bacteria suggested the Q loaded Ch-ge films as more feasible antibacterial candidate especially against the strain E. coli. The antioxidant activity of the Ch-ge-Q film was evaluated using the DPPH and ABTS as standards and corresponded to 81.45% of DPPH and 72.2% of ABTS scavenging activities. It was observed that the film containing Quercetin-starch presented superior antioxidant activity results in comparison to Ch-ge film promising its application in food packaging.
Aerobic Copper-Catalyzed Organic Reactions Allen, Scott E; Walvoord, Ryan R; Padilla-Salinas, Rosaura ...
Chemical reviews,
08/2013, Letnik:
113, Številka:
8
Journal Article
Recenzirano
Odprti dostop
Information about copper-catalyzed oxidation chemistry that uses aerobic oxygen as an oxidant is presented. Special attention is given to stoichiometric reactions with copper.
DNA nanotechnology enables engineering of molecular-scale devices with exquisite control over geometry and site-specific functionalization. This capability promises compelling advantages in advancing ...nanomedicine; nevertheless, instability in biological environments and innate immune activation remain as obstacles for in vivo application. Natural particle systems (i.e., viruses) have evolved mechanisms to maintain structural integrity and avoid immune recognition during infection, including encapsulation of their genome and protein capsid shell in a lipid envelope. Here we introduce virus-inspired enveloped DNA nanostructures as a design strategy for biomedical applications. Achieving a high yield of tightly wrapped unilamellar nanostructures, mimicking the morphology of enveloped virus particles, required precise control over the density of attached lipid conjugates and was achieved at 1 per ∼180 nm2. Envelopment of DNA nanostructures in PEGylated lipid bilayers conferred protection against nuclease digestion. Immune activation was decreased 2 orders of magnitude below controls, and pharmacokinetic bioavailability improved by a factor of 17. By establishing a design strategy suitable for biomedical applications, we have provided a platform for the engineering of sophisticated, translation-ready DNA nanodevices.
The radical intermediates formed upon UVA irradiation of titanium dioxide suspensions in aqueous and non-aqueous environments were investigated applying the EPR spin trapping technique. The results ...showed that the generation of reactive species and their consecutive reactions are influenced by the solvent properties (e.g., polarity, solubility of molecular oxygen, rate constant for the reaction of hydroxyl radicals with the solvent). The formation of hydroxyl radicals, evidenced as the corresponding spin-adducts, dominated in the irradiated TiO2 aqueous suspensions. The addition of 17O-enriched water caused changes in the EPR spectra reflecting the interaction of an unpaired electron with the 17O nucleus. The photoexcitation of TiO2 in non-aqueous solvents (dimethylsulfoxide, acetonitrile, methanol and ethanol) in the presence of 5,5-dimethyl-1-pyrroline N-oxide spin trap displayed a stabilization of the superoxide radical anions generated via electron transfer reaction to molecular oxygen, and various oxygen- and carbon-centered radicals from the solvents were generated. The character and origin of the carbon-centered spin-adducts was confirmed using nitroso spin trapping agents.
The increasing acceptance of ready to eat food generates demand on development of active and intelligent food packaging material. Even though many polymers have been used for the packaging, they have ...limitations for broad applications. Among the various polymers, Poly Vinyl Alcohol is a promising film forming polymer with highly flexible, emulsifying and adhesive properties. A variety of nano-fabrication techniques have already been reported to improve the mechanical and antimicrobial properties of PVA to exploit its wider applications. In the present study, starch-PVA based composite films incorporated with zinc oxide nanoparticles and phytochemicals were prepared by solvent casting technique. The films were characterized by XRD, FT-IR, UV–Vis spectrometry and SEM. The developed nanocomposite films were demonstrated to have enhanced water barrier, mechanical and antimicrobial properties. The unique features of the nanocomposite with its pH indication property demonstrated in the study indicate its potential usage in food packaging applications.
•pH sensing antimicrobial wraps were prepared and characterized.•Films were found to be water resistant with excellent UV-light barrier properties.•Microbial barrier ability also makes it suitable for packaging foods.
The fruits of Chinese hawthorn (Crataegus pinnatifida) have been used as the functional food and folk medicine due to potent antioxidant activity. In this study, polyphenols were extracted from the ...fruits of Chinese hawthorn and further added into chitosan-gelatin blend films to develop active packaging. The microstructure, physical, mechanical, barrier and antioxidant properties of the films were investigated in details. Results showed epicatechin, chlorogenic acid and procyanidin B2 were the main polyphenols in the extract of hawthorn fruits. The inner microstructure of chitosan-gelatin blend films became more compact when the extract was incorporated. The intermolecular interactions between film matrix and the extract were through hydrogen bonding and electrostatic interactions. The incorporation of the extract remarkably increased the thickness, tensile strength and elongation at break of chitosan-gelatin blend films. However, the moisture content, water vapor permeability and light transmittance of chitosan-gelatin blend films were significantly reduced by the addition of the extract. Moreover, chitosan-gelatin blend films containing the extract exhibited potent free radical scavenging ability. Our results suggest Chinese hawthorn fruit extract can be used as a natural antioxidant to improve the mechanical, barrier and antioxidant properties of chitosan-gelatin blend films.
•Chinese hawthorn fruit extract was added into chitosan-gelatin blend films.•Film matrix interacted with extract via hydrogen bond and electrostatic interactions.•The extract addition enhanced the mechanical and barrier properties of the films.•Films containing the extract showed dose-dependent free radical scavenging ability.
Chemical oxidation processes have been widely applied to water treatment and may serve as a tool to minimize the release of micropollutants (e.g. pharmaceuticals and endocrine disruptors) from ...municipal wastewater effluents into the aquatic environment. The potential of several oxidants for the transformation of selected micropollutants such as atenolol, carbamazepine, 17α-ethinylestradiol (EE2), ibuprofen, and sulfamethoxazole was assessed and compared. The oxidants include chlorine, chlorine dioxide, ferrate
VI, and ozone as selective oxidants versus hydroxyl radicals as non-selective oxidant. Second-order rate constants (
k) for the reaction of each oxidant show that the selective oxidants react only with some electron-rich organic moieties (ERMs), such as phenols, anilines, olefins, and deprotonated-amines. In contrast, hydroxyl radicals show a nearly diffusion-controlled reactivity with almost all organic moieties (
k
≥
10
9
M
−1 s
−1). Due to a competition for oxidants between a target micropollutant and wastewater matrix (i.e. effluent organic matter, EfOM), a higher reaction rate with a target micropollutant does not necessarily translate into more efficient transformation. For example, transformation efficiencies of EE2, a phenolic micropollutant, in a selected wastewater effluent at pH 8 varied only within a factor of 7 among the selective oxidants, even though the corresponding
k for the reaction of each selective oxidant with EE2 varied over four orders of magnitude. In addition, for the selective oxidants, the competition disappears rapidly after the ERMs present in EfOM are consumed. In contrast, for hydroxyl radicals, the competition remains practically the same during the entire oxidation. Therefore, for a given oxidant dose, the selective oxidants were more efficient than hydroxyl radicals for transforming ERMs-containing micropollutants, while hydroxyl radicals are capable of transforming micropollutants even without ERMs. Besides EfOM, ammonia, nitrite, and bromide were found to affect the micropollutant transformation efficiency during chlorine or ozone treatment.
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