Sol–gel synthesis and thermal behavior of bioactive ferrous citrate–silica hybrid materials

Imbalance of the iron level in the body causes several diseases. In particular, the low level of iron, during pregnancy, is responsible for the iron deficiency anemia, and even of neurodegenerative diseases. Although the treatment of iron deficiency anemia with oral iron supplements has been known, this problem still afflicts many people. The aim of this work was the development of a system able to release ferrous ions in a controlled manner. Controlled drug release for medical applications, indeed, appears to be a very interesting alternative to a systemic therapy because it is assurance of treatment continuity and drug stability and optimizes drug absorption. For this purpose, ferrous citrate (Fe(II)C) was synthesized by a redox reaction between iron powder and citric acid. Fourier transform infrared spectroscopy (FTIR), 1,10-phenanthroline and sodium thiocyanate colorimetric assays confirmed that only Fe(II)C was obtained by redox reaction. Afterward, obtained Fe(II)C was embedded within a SiO2 matrix in different mass percentage, by means of a sol–gel route. FTIR spectroscopy and simultaneous thermogravimetry/first-order derivative of thermogravimetry were used to confirm the Fe(II)C presence in the silica matrix and to investigate the thermal behavior of the sol–gel materials, respectively. The bioactivity test carried out by soaking the synthesized drug delivery systems in a simulated body fluid showed that the biological properties of the silica matrix are not modified by the presence of Fe(II)C

Exclusive semileptonic BB-meson decays using lattice QCD and unitarity

We present the results of the application of the Dispersion Matrix approach to exclusive semileptonic $B$-meson decays. This method allows to determine the hadronic form factors in a non-perturbative and completely model-independent way. Starting from lattice results available at large values of the momentum transfer, the behaviour of the form factors in their whole kinematical range is obtained without introducing any parameterization of their momentum dependence. We will focus on the determination of the Cabibbo-Kobayashi-Maskawa matrix elements $\vert V_{cb} \vert$ and $\vert V_{ub} \vert$ through the analysis of $B_{(s)} \to D_{(s)}^{(*)} \ell \nu$ and $B_{(s)} \to \pi(K) \ell \nu$ decays. New theoretical determinations of the Lepton Flavour Universality ratios relevant for these transitions will be also presented.Comment: 8 pages, 5 figures, 2 tables; contribution to QCD@Work - International Workshop on QCD - Theory and Experiment, 27 - 30 June 2022, Lecce (Italy). arXiv admin note: substantial text overlap with arXiv:2205.1395

The DM approach to semileptonic heavy-to-heavy and heavy-to-light BB decays

We present the results of the application of the Dispersion Matrix approach to semileptonic heavy-to-heavy and heavy-to-light $B$-meson decays. This method allows to determine the hadronic form factors in a non-perturbative and model-independent way. Starting from the available lattice results at large values of the momentum transfer, we obtain the behaviour of the form factors in their whole kinematical range without introducing any parameterization of their momentum dependence. We will focus on the determination of the Cabibbo-Kobayashi-Maskawa matrix elements $\vert V_{cb} \vert$ and $\vert V_{ub} \vert$ through the analysis of $B \to D^{(*)} \ell \nu$, $B_s \to D_s^{(*)} \ell \nu$, $B \to \pi \ell \nu$ and $B_s \to K \ell \nu$ decays. New theoretical determinations of the Lepton Flavour Universality ratios relevant for these transitions will be also presented, by focusing in particular on the $R(D_{(s)}^{(*)})$ ratios.Comment: 9 pages, 3 figures. Proceedings for the 39th International Symposium on Lattice Field Theory (Lattice 2022). arXiv admin note: substantial text overlap with arXiv:2209.15413, arXiv:2205.13952; text overlap with arXiv:2211.0723

Surface Characterization of Composite Catalysts Prepared by Sol-Gel Route

The aim of this work is to synthesize Nb-V oxide catalysts by sol gel route starting from metal alkoxides using different H2O/V ratios. Dried samples are characterized by X-ray diffraction (XRD), atomic absorption, and Brunauer-Emmett-Teller (BET) analysis. Calcination of dried materials up to 600°C in flowing air has been followed with Thermogravimetry-Fourier-transform infrared spectroscopy (TG-FTIR) spectroscopic analysis. The catalytic properties of calcined materials are tested in the oxidative dehydrogenation of ethane at 600°C. An improvement of the catalytic performances of vanadium for the gel prepared with the higher H2O/V ratio is found with respect to those of the supported catalyst due to the better interaction between vanadium and niobium

Waste recovery and circular economy: a resource from orange peels deriving from production of orange juice

In the perspective of bio-sustainable development and renewable resource technologies, by-products and waste from agro-industrial sector represent a relatively cheap source of material suitable for several aims, which would reduce both the amount of waste and the related costs of disposal, while producing added-value nutritional products. The processing waste of oranges find various fields of application, in fact in addition to their use in agriculture as a fertilizer, orange peels can be used to produce candied fruit. Moreover, in a very recent application with the aim to recover these industrial residues, a chemical process that allows the processing of orange peel waste has been developed. This process is useful for obtaining a purified cellulose suitable for spinning, thus creating a truly innovative and sustainable fabric (Orange Fiber). In this work, the orange peels obtained from industrial processing waste were subjected to a first hydroalcoholic extraction which allowed to obtain an extract rich in essential oils that could be used in the food sector to produce liqueurs and/or aromas, but also in the cosmetic or pharmacological sectors. Subsequently, the peels after hydroalcoholic extraction were dried and this residue represents a valuable product rich in dietetic fiber useful in nutraceutical and pharmaceutical fields. Moreover, the same product could be used as fertilizer in agriculture. In lights of this, citrus fruit processing waste can be considerate as a sustainable and renewable energy source

Various applications of processing of olive leaves waste extracted with RSLDE: a green technology

There is no waste in nature. Everything that is produced has a purpose and everything that becomes waste can be transformed into a new resource, triggering a virtuous circuit that feeds itself. The circular economy of waste means a system in which the production-consumption-disposal process is overcome to replace it with a circular model, where the final waste product is re-introduced into the circulation as a secondary raw material. The logic to follow is that after consumption and before any disposal, it is necessary to activate virtuous processes such as reduce, reuse and recycling. This work focuses on the possible uses of a vegetable waste matrix, such as olive leaves. The olive tree (Olea europaea) is a fruit tree, cultivated for more than 3,500 years for its fruits and edible oil. However, just like oil, olive leaf contains a high amount of polyphenols, in particular oleuropein, one of the most powerful natural antioxidants known and hydroxytyrosol, which also has powerful antiseptic properties. Therefore, olive leaf extracts, thanks to the presence of oleuropein associated with hydroxytyrosol, represent a powerful natural antioxidant, a valid ally of the cardiovascular system. In addition, olive leaves are an excellent regulator of the digestive system: they regulate intestinal transit and above all eliminate fungi and other unwanted parasites from our body. Starting from these premises, in this work, a green extraction technique such as rapid solid liquid dynamic extraction (RSLDE) is compared with conventional maceration to obtain an olive leaf extract rich in antioxidants to be used in various sectors

Synthesis by sol-gel technique and Antibacterial activity of bioactive hydrid SiO2 inorganic matrix by different structures of Ferrous citrate (Fe(II)C): comparative study

Abstract. The aim of this work was to characterize and compare three different structures of Ferrous citrate (Fe(II)C), amorphous, semi-crystalline and crystalline incorporated into a SiO2 inorganic matrix by sol-gel technique. On this system thus obtained, colorimetric assay was carried out to confirm the only presence of Fe2+; Fourier transform infrared spectroscopy (FTIR) confirmed not only the Fe(II)C presence in the silica matrix but also showed us the interactions among different components in the hybrid materials. The bioactivity of the synthesized hybrid materials was evaluated by the formation of a layer of hydroxyapatite on the surface of samples soaked in SBF using FTIR spectroscopy. Finally, the antibacterial properties of the hybrid materials were investigated

Comparative Studies on Different Citrus Cultivars: A Revaluation of Waste Mandarin Components

Peel, pulp and seed extracts of three mandarin varieties, namely Phlegraean mandarin (Citrus reticulata), Kumquat (Citrus japonica), and Clementine (Citrus clementina) were compared and characterised in terms of photosynthetic pigment content, total polyphenols amount, antioxidant activity and vitamin C to assess the amount of functional compounds for each cultivar. The highest polyphenols content was found in the Phlegraean mandarin, especially in peel and seeds, whereas Kumquat exhibited the highest polyphenols amount in the pulp. The antioxidant activity was higher in the peel of Phlegraean mandarin and clementine compared to Kumquat, which showed the highest value in the pulp. The antioxidant activity peaked in the seeds of Phlegraean mandarin. The vitamin C in the Phlegraean mandarin was the highest in all parts of the fruit, especially in the seeds. Total chlorophyll content was comparable in the peel of different cultivars, in the pulp the highest amount was found in clementine, whereas kumquat seeds showed the greatest values. As regards total carotenoids, peel and pulp of clementine exhibited higher values than the other two cultivars, whereas the kumquat seeds were the richest in carotenoids. Among the analysed cultivars Phlegraean mandarin may be considered the most promising as a source of polyphenols and antioxidants, compared to the clementine and Kumquat, especially for the functional molecules found in the seeds. Moreover, regardless of cultivars this study also highlights important properties in the parts of the fruit generally considered wastes

Extraction and purification of phycocyanin from Arthrophira platensis microalgae using a green solid-liquid extraction technology (RSLDE)

Abstract. Spirulina is a blue alga belonging to the class of Cyanobacteria. This alga is characterized by a high content of phycocyanin, a blue photosynthetic pigment belonging to the phycobiliprotein family. Phycocyanin has a lot of industrial applications, in fact, it is used as a natural dye both in the cosmetic industry and in the food and textile sectors. It is also used in the biomedical field as a fluorescent marker. Anti-inflammatory, nephroprotective and hepatoprotective properties are also reported, probably related to its antioxidant activity. However, the extraction of phycobiliproteins from cyanobacteria is a very complicated procedure due to the extreme resistance of the wall of the cellular aggregates that make up spirulina. In literature, several procedures have been used to cause rupture of cell envelopes, through cycles of freezing/thawing, sonication and rupture of the cell wall with lysozyme. However, all these methods for cell breakdown do not guarantee a high quality of the extract, due to the complexity of the mixture obtained. In order to improve the yield of recovery of phycocyanin and to reduce the extraction process time, in this work, in combination with some experimental procedures for rupture of the membrane, a green extraction technique was used, the rapid solid liquid dynamic extraction (RSLDE). This technique can generate a pressure and a consequent depression on the matrix to be extracted. The extract obtained was immediately frozen at -20°C and then lyophilized. Analyzes such as UV-VIS spectrophotometric analysis and acrylamide gel electrophoresis were performed on the sample of lyophilizate to evaluate the efficiency of the extraction and purity of phycocyanin