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Lanthanide phosphonate coordination polymers
No full textIn recent years, coordination polymers (CPs) have emerged as versatile scaffolding materials built from various metal ions and organic ligands, and these materials are highly investigated for their use in numerous applications. In particular, coordination polymers including lanthanide ions (Ln) are very promising because these ions transfer some interesting luminescence features to the frameworks, such as sharp emission, long lifetimes, large Stokes’ shift and high color purity. Although much research focusses on carboxylate-type ligands for the preparation of coordination polymers owing to their ability to form porous structures, organophosphonates appear to be promising ligands as well. In fact they display higher coordination versatility and they are able to bridge a large number of metal cations enhancing the metal density and allowing for the introduction of multiple functionalities in the heterometallic structures. Moreover, thanks to the proton exchange properties of the phosphonate groups, these materials can display remarkable proton conduction properties. In the current review, lanthanide phosphonates assembling 1-, 2- and 3-dimensional (D) coordination polymers are described, and their value in different applications will be outlined. From the literature survey, it emerges that 1D structures with an extended hydrogen bonding network were the most promising materials for proton conduction, while 2D structures were mainly investigated for their luminescent and magnetic properties. In many examples the luminescence of 3D lanthanide coordination polymers could be changed by incorporating small molecules or metal ions, which opens up new possibilities for their use as straightforward sensor materials.Peer-reviewed version: [https://riofh.iofh.bg.ac.rs/handle/123456789/1018
Study of two edible Polygonoideae Plants: antimicrobial activity, prebiotic properties and valorization potential of solid waste remaining after extract production
No full textThe Effects of rGO Content and Drying Method on the Textural, Mechanical, and Thermal Properties of rGO/Polymer Composites
No full textComposite hydrogels samples consisting of poly(methyl methacrylate/butyl acrylate/2-hydroxyethylmethacrylate) (poly-OH) and up to 60% reduced graphene oxide (rGO) containing rGO were synthesized. The method of coupled thermally induced self-assembly of graphene oxide (GO) platelets within a polymer matrix and in situ chemical reduction of GO was applied. The synthesized hydrogels were dried using the ambient pressure drying (APD) and freeze-drying (FD) methods. The effects of the weight fraction of rGO in the composites and the drying method on the textural, morphological, thermal, and rheological properties were examined for the dried samples. The obtained results indicate that APD leads to the formation of non-porous xerogels (X) of high bulk density (D), while FD results in the formation of highly porous aerogels (A) with low D. An increase in the weight fraction of rGO in the composite xerogels leads to an increase in D, specific surface area (SA), pore volume (Vp), average pore diameter (dp), and porosity (P). With an increase in the weight fraction of rGO in A-composites, the D values increase while the values of SP, Vp, dp, and P decrease. Thermo-degradation (TD) of both X and A composites takes place through three distinct steps: dehydration, decomposition of residual oxygen functional group, and polymer chain degradation. The thermal stabilities (TS) of the X-composites and X-rGO are higher than those of the A-composites and A-rGO. The values of the storage modulus (E') and the loss modulus (E") of the A-composites increase with the increase in their weight fraction of rGO
Molecular Approaches for Detection of Trichoderma Green Mold Disease in Edible Mushroom Production
No full textSimple Summary The green mold disease caused by the pathogenic fungi Trichoderma spp. is the most harmful disease for edible mushroom production. This disease's harmful effect is due to the belated detection of the green mold disease, which occurs when the damage to the yield is irreversible. Severe epidemics of green mold started during the 1980s and 1990s in Europe and America and triggered the development of molecular approaches for the monitoring and detection of Trichoderma. The most promising molecular tools are nucleic acid (NA)-based methods. In this review, we discuss the currently most-used molecular methods for green mold detection and introduce an NA-based isothermal amplification methodology suitable for the development of point-of-need (PON) devices for field applications in detecting this disease. Due to the evident aggressive nature of green mold and the consequently huge economic damage it causes for producers of edible mushrooms, there is an urgent need for prevention and infection control measures, which should be based on the early detection of various Trichoderma spp. as green mold causative agents. The most promising current diagnostic tools are based on molecular methods, although additional optimization for real-time, in-field detection is still required. In the first part of this review, we briefly discuss cultivation-based methods and continue with the secondary metabolite-based methods. Furthermore, we present an overview of the commonly used molecular methods for Trichoderma species/strain detection. Additionally, we also comment on the potential of genomic approaches for green mold detection. In the last part, we discuss fast screening molecular methods for the early detection of Trichoderma infestation with the potential for in-field, point-of-need (PON) application, focusing on isothermal amplification methods. Finally, current challenges and future perspectives in Trichoderma diagnostics are summarized in the conclusions
INNOVATIVE INGREDIENTS FOR YOGURT PRODUCTION IN FUNCTION OF THE DEVELOPMENT OF THE AGRI-FOOD SECTOR
No full textMushroom beta-glucan and polyphenol formulations as natural immunity boosters and balancers: nature of the application
No full textMushrooms are experiencing a kind of renaissance as a part of the contemporary human diet. These valuable organisms are more than food, they fit in perfectly as a novel market group known as nuts-mycoceuticals. Immune-balancing mushroom dietary fibers and secondary metabolites such as polyphenols are the main focus of the healthcare industry. Wellness and cosmetic companies arc increasingly using mushroom extracts rich in these ingredients. This review considers the basic molecular immunomodulatory mechanisms of action of the most commonly used mushroom dietary fibers, beta-glucans. The literature data on their bioavailability, metabolic transformations, preclinical and human clinical research, and safety are discussed. Immunomodulatory mechanisms of polyphenol ingredients are also considered. These molecules present great potential in the design of the new immunity balancer formulations according to their widespread structural diversity. Finally, we draw attention to the perspectives of modern trends in mushroom nutraceutical and cosmeceutical formulations to strengthen and balance immunity
Anion-Induced Structural Diversity and Optical Chromism in a Series of Cyano-Bridged Heterometallic 3d-4f Coordination Polymers
No full textThe self-assembly reaction of the neutral dicyano-bis(1,10-phenanthroline) iron(II) complex with lanthanide ions (Ln = Eu(III), Gd(III), Er(III)) provided two different classes of heterometallic cyano-bridged 3d-4f architectures depending on the nature of the counteranion, irrespective of the size of the 4f metal ion. Tetranuclear oligomers with a squared Fe(2)Ln(2) core were isolated when using nitrate salts, whereas unusual 1D polymeric chains were obtained when resorting to triflate salts under the same synthetic conditions. It is shown that the different structural motifs have a remarkable impact on the thermal stability and the optical properties of the compounds, which display a notable optical ipsochromism of the parent Fe(II) complex upon coordination with the Ln ion. This effect is significantly more pronounced in the polymeric chain than in the Fe(2)Ln(2) oligomer both in solution and in the solid state. Structural evidence suggests that this behavior is likely related to the geometry of the CN-Ln bridge. On the other hand, more extended pi-stacking interactions in the oligomer give rise to a broad charge-transfer absorption (600-1500 nm), making this compound promising as NIR absorber. Density Functional Theory calculations and electrochemical studies demonstrate that the observed negative chromism originates from the stabilization of a mixed metal/cyanide character HOMO with respect to a phenanthroline-centered LUMO
Effect of Beetroot Powder Incorporation on Functional Properties and Shelf Life of Biscuits
No full textThe demand for ready-to-use functional foods is high, which encourages manufacturers to develop new, nutritionally valuable products. As an excellent source of biologically active compounds, beetroot (Beta vulgaris L.) is considered to have highly beneficial effects on health. This research aimed to evaluate the impact of replacing spelt flour (SF) with 15%, 20% and 25% beetroot powder (BP). The physicochemical and functional properties of biscuits baked at different temperatures (150 and 170 degrees C) were followed at the beginning, and after 3 and 6 months of storage as standard conditions. Moisture content and water activity (aw) gave insight into the biscuits' shelf life. The value of aw from 0.35 to 0.56 indicated appropriate storability. Dietary fiber content in fresh biscuits ranged from 6.1% to 7.6%, protein from 9.2% to 8.9% and sugar from 30.6% to 35.9%. The content of betalain, total polyphenols and flavonoids, and antioxidant activity (DPPH, FRAP) increased with beetroot powder content incorporated. A slight decrease of all the mentioned parameters during the storage indicated satisfied retention of bioactive molecules. The content of prevalent phenolic compounds gallic and protocatechuic acid, identified by HPLC, decreased from 22.2-32.0 and 21.1-24.9 in fresh biscuits to 18.3-23.4 and 17.3-20.3 mg/100 g upon six months of storage, respectively. An increase of the L* and a* and a decrease of the b* coordinate values, compared with the control sample without beetroot values, was noticed as well as the expected level of their change during the storage. The obtained results indicated that biscuits enriched with beetroot powder showed a significantly improved functional, nutritional and antioxidant potential during storage
The Influence of Biopolymer Coating Based on Pumpkin Oil Cake Activated with Mentha piperita Essential Oil on the Quality and Shelf-Life of Grape
No full textThis work aimed to determine the influence of biopolymer coatings based on pumpkin oil cake, with and without the addition of Mentha piperita essential oil, on the quality and shelf-life of the Afus Ali variety of grapes, stored at room temperature and in the refrigerator. Furthermore, a 10% (w/w) aqueous solution of composite pumpkin oil cake (PuOC) with the addition of 30% glycerol was prepared at 60 degrees C and pH 10. The active biopolymer coating was prepared similarly by adding 1% (v/v) Mentha piperita essential oil. The quality of packed grapes was tested by determining the dry matter content, total sugar content, total acidity, alcohol content, total phenolic compounds content, and total flavonoid content, as well as by determining the antioxidant activity, through the application of the DPPH, FRAP and ABTS tests. Additionally, microbiological parameters were investigated: total aerobic microbial count, yeasts, and molds. The obtained results proved that in all tested samples, over a certain period of time, the content of dry matter, content of phenolic and flavonoids substances and sugar content decreased as a consequence of the spoilage of grapes, that is, the consumption of sugar for the production of alcohol, which consequently leads to the total acidity increasing. The application of lower storage temperatures and active coating (with Mentha piperita essential oil) had a positive effect on all inevitable reactions. Grapes' antioxidant potential may be enhanced or maintained by applying PuOC coating with or without Mentha piperita essential oil, which is best observed in the case of the DPPH test. The uncoated sample stored at room temperature had the largest decrease in DPPH values during storage, with changes ranging from 2.119 mg/g to 1.471 mu mol mg/g. The samples, coated with PuOC and PuOC with the addition of essential oil, had uniform DPPH values throughout the entire storage period. Additionally, regarding phenolic content, at the end of storage period the highest phenolic content was observed in samples with active coating stored at room temperature (734.746 +/- 2.462) and at refrigerator temperature (680.827 +/- 0.448) compared with untreated samples and with samples with plain PuOC coating. The presence of active essential oil in the applied coating significantly affected the microbiological profile of grapes during the storage period. Besides the positive impact of the applied lower storage temperature, the effectiveness of the applied active packaging is even greater (microbiological results were in the order of PuOC+essential oil LT PuOC LT Control). The developed artificial neural networks were found to be adequate for modeling the microbiological profile, antioxidant activity, phenolic and flavonoid content