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811.
The present research is based on a survey sent to large, medium and small size companies, located in Portugal and within what are considered the most pollutant industrial sectors. The analyses of the results, processed with the Statistical Package for Social Sciences (SPSS) 11.0, show that generally companies are concerned with the implementation of clean processes, green products and eco-equipment to have a cleaner environment, i.e. a more sustainable society. Statistically, the results show that the 98 potential polluting companies are moderately contributing for a green society (xm=3.1) regarding the ten environmental strategies under research. It can also be concluded that, globally, environmental strategies are directly linked to the companies’ size.  相似文献   
812.
Drug delivery systems, accompanied by nanoparticle technology, have recently emerged as prominent solutions to improve the pharmacokinetic properties, namely bioavailability, of therapeutic and nutraceutical agents. Solid lipid nanoparticles (SLNs) have received much attention from researchers due to their potential to protect or improve drug properties. SLNs have been reported to be an alternative system to traditional carriers, such as emulsions, liposomes, and polymeric nanoparticles. Phenolic compounds are widespread in plant-derived foodstuffs and therefore abundant in our diet. Over the last decades, phenolic compounds have received considerable attention due to several health promoting properties, mostly related to their antioxidant activity, which can have important implications for health. However, most of these compounds have been associated with poor bioavailability being poorly absorbed, rapidly metabolized and eliminated, which compromises its biological and pharmacological benefits. This paper provides a systematic review of the use of SLNs as oral delivery systems of phenolic compounds, in order to overcome pharmacokinetic limitations of these compounds and improved nutraceutical potential. In vitro studies, as well as works describing topical and oral treatments will be revisited and discussed. The classification, synthesis, and clinical application of these nanomaterials will be also considered in this review article.  相似文献   
813.
814.
Million tons of brewer’s spent grain (BSG) are annually produced worldwide as brewing industry by-products. BSG represents a valuable source of phenolic compounds, which have attracted much attention due to their diverse health benefits. Relevant strategies have been developed for their efficient extraction, in order to commercially exploit these resources. This review focuses on the current extraction methods used to obtain phenolic compounds from BSG, ranging from more traditional to advanced techniques. The commonly used methods are the conventional solid–liquid extractions, employing organic solvents, alkaline, and enzymatic reactions. However, the inherent difficulties in screening and obtaining these compounds have led to the development of advanced extraction techniques. Pressurized fluid extraction, supercritical extractions, and microwave-assisted and ultrasound-assisted extractions are some of the novel extraction techniques that have been recently explored. These techniques have been mostly applied for phenolic recovery from barley and malt, as well as other types of cereals. In this review, it is shown that these novel techniques may provide an innovative approach to extract phenolics from BSG or related products, following an in-depth discussion on the major strengths and weaknesses identified in each technique.  相似文献   
815.
Multifunctional hydrogels based on chitosan–quercetin (CHITQ) conjugate are prepared by a thermo‐induced radical procedure in the presence of N‐isopropylacrylamide (NIPAAm), acrylamide (AAm), and N,N′‐methylenebis(acrylamide) (MEBA). At first, quercetin (Q) is grafted onto chitosan backbone with a functionalization degree of 275 mg of Q per gram of conjugate, as calculated by 1H‐NMR analyses to impart antioxidant properties to the polysaccharide. Then, a pH and temperature sensitive hydrogel was obtained by involving CHITQ and NIPAAm in the polymerization reaction. The accessibility of phenolic moieties is modified in response to the hydrogel swelling/deswelling, as confirmed by antioxidant tests performed at different temperatures. Dual stimuli‐responsive hydrogels are proposed for the delivery of caffeine as model drug. The release profiles of caffeine depict a system particularly performing as on/off device at acidic pH with excellent applicability prospects.  相似文献   
816.
The development of immunoproteasome-selective inhibitors is a promising strategy for treating hematologic malignancies, autoimmune and inflammatory diseases. In this context, we report the design, synthesis, and biological evaluation of a new series of amide derivatives as immunoproteasome inhibitors. Notably, the designed compounds act as noncovalent inhibitors, which might be a promising therapeutic option because of the lack of drawbacks and side effects associated with irreversible inhibition. Among the synthesized compounds, we identified a panel of active inhibitors with Ki values in the low micromolar or sub-micromolar ranges toward the β5i and/or β1i subunits of immunoproteasomes. One of the active compounds was shown to be the most potent and selective inhibitor with a Ki value of 21 nm against the single β1i subunit. Docking studies allowed us to determine the mode of binding of the molecules in the catalytic site of immunoproteasome subunits.  相似文献   
817.
818.
819.
The concentration levels, distribution, and seasonal fluctuations of 12 organophosphorus flame retardants and plasticizers (OPs), of which some are reported to be toxic to aquatic organisms, were investigated in lakes from June 2006 to June 2007. Three volcanic lakes located in the Lazio area (Central Italy) and characterized by a different anthropical impact were selected. Analysis of lake water samples showed that in closed ecosystems (hydrogeological systems), such as small volcanic lakes, OP contamination may occur even in the absence of industries and treated or untreated waste discharges. The selected substances were found at ng/L concentrations in all lakes. In the two more anthropized lakes tributyl phosphate and tripropyl phosphate were the most abundant OPs, with peaks of respectively 784 and 951 ng/L. Maximum pollution levels were reached in October-November, and concentrations decreased to a minimum value in March-April. Chlorinated OPs showed the same trend, but their concentrations were 1 order of magnitude lower and the level decreasing was shifted with respectto alkyl OPs. On the contrary, tris(2-butoxyethyl) phosphate concentrations were quite similar among all water samples analyzed, indicating that their sources were different in nature. One of the three lakes is an important source of drinkable water, so nine wells situated in its neighborhood were also examined. No correlation between lake water and groundwater contamination could be found.  相似文献   
820.
A study on the self-assembly of regiochemically differentiated methyl substituted quaterthiophenes is presented. Hierarchical self-assembly of 5,4′,3″,5?-tetramethyl-2,2′:5′,2″:5″,2?-quaterthiophene molecule, 7 leads to unprecedented fluorescent superstructures on glass and mica surfaces made by reiteration of a peculiar V-shaped recurring motif that extended at least for three generations.  相似文献   
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