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According to circular bioeconomy principles, the use of kiwi peels to remove Direct Blue 78 (DB) from water is investigated during this work, proposing food waste as a recyclable adsorbent substrate. Direct Blue 78 (DB) was adopted as a model pollutant, employing its visible spectrum to monitor its adsorption. The adsorption process was thus fully characterized, investigating the roles of ionic strength, pH values, adsorbent/pollutant amounts, and temperature. The thermodynamics, kinetics, and adsorption isotherms were also studied. To extend the kiwi peels' lifetime, quite complete desorption was obtained by adopting hot water as a safe and eco-friendly strategy. Despite the relatively low kiwi peels' maximum adsorption capacity (6 mg g-1) for DB when adsorbed in the presence of NaCl, 10 cycles of adsorption/desorption were attempted, proposing the recycling of both the dye and kiwi peels as dictated by circular economy principles. Dyeing experiments were also performed, evidencing the dye's ability to color cotton fabrics after its recycling. Finally, the removal of other textile dyes, Direct Red 83 : 1 and Direct Yellow 86, was demonstrated in a mixture with DB. A preliminary investigation was performed to find the best working conditions for inducing the solid-state dye photodegradation, proposing a possible alternative for the adsorbent regeneration.
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In this work, the great performance of chitosan-based films blended with TiO2 (CH/TiO2) is presented to adsorb the hazardous pollutant 2,4-dinitrophenol (DNP) from water. The DNP was successfully removed, with a high adsorption %: CH/TiO2 exhibited a maximum adsorption capacity of 900 mg/g. For pursuing the proposed aim, UV-Vis spectroscopy was considered a powerful tool for monitoring the presence of DNP in purposely contaminated water. Swelling measurements were employed to infer more information about the interactions between chitosan and DNP, demonstrating the presence of electrostatic forces, deeply investigated by performing adsorption measurements by changing DNP solutions' ionic strength and pH values. The thermodynamics, adsorption isotherms, and kinetics were also studied, suggesting the DNP adsorption's heterogeneous character onto chitosan films. The applicability of pseudo-first- and pseudo-second-order kinetic equations confirmed the finding, further detailed by the Weber-Morris model. Finally, the adsorbent regeneration was exploited, and the possibility of inducing DNP desorption was investigated. For this purpose, suitable experiments were conducted using a saline solution that induced the DNP release, favoring the adsorbent reuse. In particular, 10 adsorption/desorption cycles were performed, evidencing the great ability of this material that does not lose its efficiency. As an alternative approach, the pollutant photodegradation by using Advanced Oxidation Processes, allowed by the presence of TiO2, was preliminary investigated, opening a novel horizon in the use of chitosan-based materials for environmental applications.
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Quitosano , Contaminantes Ambientales , Contaminantes Químicos del Agua , 2,4-Dinitrofenol , Agua , Quitosano/química , Adsorción , Termodinámica , Cinética , Contaminantes Químicos del Agua/química , Concentración de Iones de HidrógenoRESUMEN
The development of food packaging materials that reduce the production of plastic, preserving at the same time the quality of food, is a topic of great interest today for the scientific community. Therefore, this article aims to report the effectiveness of an eco-friendly packaging material based on alginic acid and grape pomace extract from Vitis vinifera L. (winemaking by-products) for storing red meat in a domestic refrigerator. Specifically, biogenic amines are considered "sentinels" of the putrefactive processes, and their presence was thus monitored. For this purpose, an experimental analytical protocol based on the use of solid-phase microextraction coupled with gas chromatography-mass spectrometry was developed during this work for the determination of six biogenic amines (butylamine, cadaverine, isobutylamine, isopentylamine, putrescine, and tyramine). Moreover, by combining the analytical results with those of pH and weight loss measurements, differential scanning calorimetry, and microbiological analysis, it was proved that the studied materials could be proposed as an alternative packaging material for storing foods of animal origin, thus lowering the environmental impact according to sustainability principles.
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Vitis , Animales , Vitis/química , Alginatos , Aminas Biogénicas , Carne/análisis , Extractos VegetalesRESUMEN
Water-resistant and environmentally friendly sodium-alginate-based films have been investigated to develop functional materials to extend the food's shelf-life. A water-stable alginate-based film was prepared, employing both the internal and external gelation approach in the presence of CaCl2. To apply this film to food packaging and thus preserve food quality, the aim of this work is to perform a chemical and physical characterization of the proposed materials, evidencing the main features and stability under different work conditions. Water contact angle measurements showed a value of 65°, suggesting an important reduced hydrophilic character of the obtained alginate films due to the novel CaCl2-induced compacted polymer network. The film's stability was thus checked through swelling measurements in water after varying pH, temperature, and ionic strength. The film was stable at high temperatures and not pH-responsive. Only highly concentrated salt-based solutions negatively affected the proposed packaging, causing a large swelling. Furthermore, a water-based polyphenolic extract from grape (Vitis vinifera L.) pomace waste was embedded inside the films in different amounts in order to confer additional properties. The extract's polyphenolic content (evaluated from HPLC/MS-MS measurements) endowed the films' UV-light screening and enhanced antioxidant properties. These important findings suggest the additional potential role of these films in protecting food from light deterioration. The stability of these hybrid films was also checked by observation, as the polyphenols' presence did not largely alter the alginate network that occurred yet was water-resistant under the described work conditions.
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Alginatos , Vitis , Alginatos/química , Embalaje de Alimentos , Agua , Extractos Vegetales/farmacología , Cloruro de Calcio , SodioRESUMEN
FINEAU (2021-2024) is a trans-disciplinary research project involving French, Serbian, Italian, Portuguese and Romanian colleagues, a French agricultural cooperative and two surface-treatment industries, intending to propose chènevotte, a co-product of the hemp industry, as an adsorbent for the removal of pollutants from polycontaminated wastewater. The first objective of FINEAU was to prepare and characterize chènevotte-based materials. In this study, the impact of water washing and treatments (KOH, Na2CO3 and H3PO4) on the composition and structure of chènevotte (also called hemp shives) was evaluated using chemical analysis, X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, X-ray computed nanotomography (nano-CT), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, solid state NMR spectroscopy and thermogravimetric analysis. The results showed that all these techniques are complementary and useful to characterize the structure and morphology of the samples. Before any chemical treatment, the presence of impurities with a compact unfibrillated structure on the surfaces of chènevotte samples was found. Data indicated an increase in the crystallinity index and significant changes in the chemical composition of each sample after treatment as well as in surface morphology and roughness. The most significant changes were observed in alkaline-treated samples, especially those treated with KOH.
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Cannabis/química , Productos Agrícolas/química , Residuos/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Europa (Continente) , Humanos , Cinética , Ensayo de Materiales , TermogravimetríaRESUMEN
Due to the negative effects of emerging contaminants on the environment, that can potentially induce deleterious effects in aquatic and human life, this paper focuses on the removal from the water of Furosemide, through the adsorption process. Indeed, only a few papers are available in the literature about the Furosemide adsorption and, chitosan films are thus proposed for this purpose as safe, sustainable, and recyclable adsorbent materials. In the present work, the effects on the adsorption process of several experimental parameters such as the pH values, ionic strength, amount of adsorbent/pollutant, and temperature values were investigated. The kinetics models, isotherms of adsorption, and the thermodynamic parameters were studied showing that the Furosemide physisorption occurred on the heterogeneous Chitosan surface, endothermically (ΔH° = +31.27 ± 3.40 kJ mol-1) and spontaneously (ΔS° = +150.00 ± 10.00 J mol-1 K-1), following a pseudo-second-order kinetic model. The 90% of the pollutant was adsorbed in 2 h, with a maximum adsorption capacity of 3.5 mg × g-1. Despite these relatively low adsorption capacities, experiments of desorption were performed and 100% of adsorbed Furosemide was recovered by using concentrated NaCl solutions, proposing a low-cost and green approach, with respect to the previous literature relative to the Furosemide adsorption, fundamental for the pollutant recovery and adsorbent reuse.
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Quitosano/química , Furosemida/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Adsorción , Humanos , Concentración de Iones de Hidrógeno , Cinética , Temperatura , TermodinámicaRESUMEN
In this work, for the first time, snail slime from garden snails "Helix Aspersa Müller", has been used to induce the formation of eco-friendly gold nanoparticles (AuNPs-SS) suitable for biomedical applications. An AuNPs-SS comprehensive investigation was performed and AuNPs with an average particle size of 14 ± 6 nm were observed, stabilized by a slime snail-based organic layer. Indeed, as recognized in high-resolution MALDI-MS analyses, and corroborated by FESEM, UV-Vis, ATR-FTIR, and XPS results, it was possible to assess the main presence of peptides and amino acids as the main components of the slime, that, combined with the AuNPs confers on them interesting properties. More specifically, we tested, in vitro, the AuNPs-SS safety in human keratinocytes and their potential effect on wound healing as well as their anti-inflammatory properties in murine macrophages. Moreover, the AuNPs-SS treatment resulted in a significant increase of the urokinase-type plasminogen activator receptor (uPAR), essential for keratinocyte adhesion, spreading, and migration, together with the reduction of LPS-induced IL1-ß and IL-6 cytokine levels, and completely abrogated the synthesis of inducible nitric oxide synthase (iNOS).
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Oro , Nanopartículas del Metal , Animales , Antiinflamatorios/farmacología , Humanos , Ratones , Moco , Caracoles , Cicatrización de HeridasRESUMEN
Since several years the inclusion of organic compounds (guests) within the hydrophobic cavity (host) of cyclodextrins (CDs) has been the subject of many investigations. Interestingly, the formation of inclusion complexes could affect the properties of the guest molecules and, for example, the influence of the delivery system can be a method to improve/change the photochemical behavior of the guest. In particular, very recent studies have shown the protective role of CDs preventing the degradation of the encapsulated guest. Starting from this consideration, in this work, only the structure and complexation mode of the inclusion complexes involving 4-thiothymidine (S(4)TdR, a known photosensitizer) and five CDs, namely 2-hydroxypropyl-α-cyclodextrin (2-HP-α-CD), 2-hydroxypropyl-ß-cyclodextrin (2-HP-ß-CD), 2-hydroxypropyl-γ-cyclodextrin (2-HP-γ-CD), heptakis-(2,6-di-O-methyl)-ß-cyclodextrin (DIMEB CD) and heptakis-(2,3,6-tri-O-methyl)-ß-cyclodextrin (TRIMEB CD) were investigated by different spectroscopic techniques (UV-vis, FTIR-ATR, (1)H NMR) and cyclic voltammetry analysis (CV). This work is necessary for a prospective research on the photoreactivity of S(4)TdR in aqueous environment and in the presence of CDs to prevent its degradation under irradiation. UV-vis, FTIR-ATR and CV measurements suggested the formation of supramolecular structures involving the employed CDs and mainly the pyrimidine ring of S(4)TdR. (1)H NMR analyses confirmed such indication, unveiling the presence of inclusion complexes. The strongest and deepest interactions were suggested when TRIMEB and DIMEB CDs were studied. The S(4)TdR affinity towards CDs was also evaluated by using the Benesi-Hildebrand (B-H) equation at 25 °C employing CV and (1)H NMR methods. The stoichiometry of the interaction was also inferred and it appears to be 1:1 for all examined CDs.
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The photoreactivity of 4-thiothymidine (S(4)TdR) under visible light in the presence of Rose Bengal (RB), acting as a photosensitizer, was investigated in aqueous solutions at pH 7 and 12, using UV-vis, FTIR-ATR and (1)H-NMR spectroscopic techniques, time resolved absorption spectroscopy and electrospray ionization mass spectrometry (ESI-MS). Evidence for the generation of thymidine (TdR) as the main product, after one hour of irradiation, was obtained from UV-Vis data, that suggested 4-thiothymidine photodegradation to be faster at basic pH, and confirmed by FTIR-ATR and (1)H-NMR data. Clues for the presence of a further product, likely corresponding to a dimeric form of S(4)TdR, were obtained from the latter techniques. Besides indicating the presence of thymidine, the ESI-MS and MS/MS spectra of the reaction mixtures enabled the identification of the additional product as a S-S bridged covalent dimer of 4-thiothymidine. The concentration of the dimeric species could be estimated with the aid of (1)H-NMR data and was found to be lower than that of thymidine in pH 7 reaction mixtures and almost negligible in the pH 12 ones. From a mechanistic point of view, time-resolved absorption spectroscopy measurements provided direct evidence that the formation of the two products cannot be ascribed to a photoinduced electron transfer involving S(4)TdR and the excited triplet state of RB. Rather, their generation can be interpreted as the result of a bimolecular reaction occurring between singlet state oxygen ((1)O2), photogenerated by RB, and S(4)TdR, as demonstrated by the direct detection of (1)O2 through IR luminescence spectroscopy. More specifically, a sequential reaction pathway, consisting in the generation of an electrophilic hydroxylated form of S(4)TdR and its subsequent, rapid reaction with S(4)TdR, was hypothesized to explain the presence of the S-S bridged covalent dimer of 4-thiothymidine in the reaction mixtures. The described processes make S(4)TdR an interesting candidate in the role of molecular probe for the detection of (1)O2 under different pH conditions.
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Fotólisis , Fármacos Fotosensibilizantes/química , Rosa Bengala/química , Oxígeno Singlete/química , Timidina/análogos & derivados , Luz , Modelos Moleculares , Oxidación-Reducción , Tionucleósidos/química , Timidina/químicaRESUMEN
Nanostructured films based on Au nanorods (NRs) have been obtained by layer-by-layer (LbL) assembly driven by electrostatic interaction between metal nanoparticles and polyelectrolytes. Multilayer films have been fabricated by using LbL assembly of poly(sodium styrenesulfonate) (PSS) and positively charged Au NRs on a polyelectrolyte-modified substrate. The effect of fabrication parameters, including the nature of the substrate, the polyelectrolyte initial anchoring layer, and the number of layers has been investigated by means of UV-vis absorbance spectroscopy and atomic force microscopy (AFM). The results demonstrated the dependence of morphology and plasmonic features in the multilayered nanostructured architectures from the nature of the anchoring polyelectrolyte on the substrate, the number of layers, and the kind of NR mutual assembly. In addition, a study of the electrochemical activity at the solid/liquid interface has been carried out in order to assess charge transport through the NR multilayer by using two molecular probes in solution, namely, potassium ferricyanide, a common and well-established redox mediator with reversible behavior, and cytochrome C, a robust model redox protein. The presented systematic study of the immobilization of Au NRs opens the venue to several application areas, such as (bio)chemical sensing.
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Oro/química , Nanotubos/química , Microscopía de Fuerza Atómica , Nanotecnología , Poliestirenos/químicaRESUMEN
Due to the pollution problem, the use of more sustainable materials with a reduced environmental impact, spanning across biocompatible and biodegradable polymers, is growing worldwide in many different fields, particularly when referring to applications in Life Sciences. Accordingly, with the aim of developing multifunctional materials for potential cosmetic/biomedical purposes, this work reports the physical and chemical characterization of chitosan-based films blended with snail slime, exhibiting antioxidant and sunscreen features. A suitable formulation for preparing free-standing chitosan platforms, mixing low molecular weight chitosan, lactic acid, glycerol, and snail slime into an appropriate ratio, is thus described. The results obtained by morphological analysis and ATR-FTIR spectroscopy, XRD, swelling analysis (also when varying pH, ionic strength, and temperature), and WVTR measurements evidence a uniform distribution of snail slime inside the chitosan network, forming more compacted structures. At first, the UV-Vis analysis is used to investigate the theoretical Sun Protection Factor, finding that these innovative platforms can be used for preventing sunburn. Then, the antioxidant features are investigated using the ABTS assay, displaying a snail slime-mediated and dose-dependent boosted activity.
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Quitosano , Quitosano/química , Antioxidantes , Polímeros , Protectores Solares , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Interfacing intact and metabolically active photosynthetic bacteria with abiotic electrodes requires both establishing extracellular electron transfer and immobilizing the biocatalyst on electrode surfaces. Artificial approaches for photoinduced electron harvesting through redox polymers reported in literature require the separate synthesis of artificial polymeric matrices and their subsequent combination with bacterial cells, making the development of biophotoanodes complex and less sustainable. Herein, we report a one-pot biocompatible and sustainable approach, inspired by the byssus of mussels, that provides bacterial cells adhesion on multiple surfaces under wet conditions to obtain biohybrid photoanodes with facilitated photoinduced electron harvesting. Purple bacteria were utilized as a model organism, as they are of great interest for the development of photobioelectrochemical systems for H2 and NH3 synthesis, biosensing, and bioremediation purposes. The polydopamine matrix preparation strategy allowed the entrapment of active purple bacteria cells by initial oxygenic polymerization followed by electrochemical polymerization. Our results unveil that the deposition of bacterial cells with simultaneous polymerization of polydopamine on the electrode surface enables a 5-fold enhancement in extracellular electron transfer at the biotic/abiotic interface while maintaining the viability of the cells. The presented approach paves the way for a more sustainable development of biohybrid photoelectrodes.
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During the last decades, the demand for processes developed according to the Circular Economy Principles has increased, searching for an alternative life for wastes. For this purpose, a one-pot green approach is exploited during this work to synthesize gold nanoparticles (AuNPs) by using grape pomace waste from Vitis vinifera. A raw aqueous extract of grape seeds, skin, and stems is used for AuNPs synthesis. UV-Vis, XPS, SEM, and ATR-FTIR spectroscopies demonstrate the main role of the extract's polyphenolic components in stabilizing nanoparticles. XRD, DLS, and Zeta Potential analyses were used to characterize AuNPs. Moreover, the ionic strength, pH, and temperature role was investigated through the Surface Plasmon Resonance (SPR) band observation to assess AuNPs' stability and photostability. For foreseeing the as-synthesized AuNPs' potential use in cosmetic and biomedical fields as multifunctional platforms, their antioxidant, and skin-lightening properties were tested, together with their sunscreen ability. A preliminary in-vitro evaluation is reported about the AuNPs' cytoprotective effects against H2O2 oxidative stress-induced in normal human dermal fibroblasts. Briefly, the possibility of reusing the grape pomace waste after the AuNPs synthesis as an adsorbent for the efficient removal of emergent contaminants is preliminarily discussed in the paper, further valorizing the use of waste according to a bio circular approach.
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Due to their properties, snail slime-based products have been appreciated and used worldwide. So, as an alternative and innovative use of snail slime, it was adopted to induce gold nanoparticles' formation, conferring them interesting properties. By a simple, one-pot, and eco-friendly approach, 14 ± 6 nm wide hybrid gold nanoparticles, having an inorganic metallic core decorated by the slime's main components, were obtained. Among their several properties, their antioxidant and tyrosinase inhibition activity were investigated through the DPPH and ABTS and the tyrosinase assays, respectively. After assessing their non-cytotoxicity in our previous work, the results revealed positive responses, enabling their use as a potential novel multifunctional ingredient in cosmetics. Interestingly, the gold nanoparticle photostability, investigated by means of a solar simulator lamp, suggests using them in commercial cosmetic sunscreen products as a potential alternative to the commonly used inorganic sunscreen ingredients. The theoretical Sun Protection Factor was evaluated, obtaining values in the range 0-12. The proposed environmentally friendly and cost-effective protocol for nanoparticle synthesis, following the principles of Green Chemistry, opens a hugely attractive space toward the study of snail slime-based gold nanoparticles as a potential multipurpose platform in cosmetics.
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Antioxidantes/farmacología , Cosméticos/química , Inhibidores Enzimáticos/farmacología , Oro/química , Nanopartículas del Metal/química , Monofenol Monooxigenasa/antagonistas & inhibidores , Moco , Caracoles , Protectores Solares/farmacología , AnimalesRESUMEN
The aim of this paper is to present and characterize Polyamidoamine-based hydrogels (PAA) as scaffolds to host photoactive Chlorophyll a (Chl a) from Spirulina (Arthrospira platensis) sea-weed Extract (SE), for potential applications in Photodynamic Therapy (PDT). The pigment extracted from SE was blended inside PAA without further purification, according to Green Chemistry principles. A comprehensive investigation of this hybrid platform, PAA/SE-based, was thus performed in our laboratory and, by means of Visible absorption and emission spectroscopies, the Chl a features, stability and photoactivity were studied. The obtained results evidenced the presence of two main Chl a forms, monomeric and dimeric, interacting with hydrogel polyamidoamines network. To better understand the nature of this interaction, the spectroscopic investigation of this system was performed both before and after the solidification of the hydrogel, that occurred at least in 24 h. Then, focusing the attention on solid scaffold, the 1Chl aâ fluorescence lifetime and FTIR-ATR analyses of PAA/SE were carried out, confirming the findings. The swelling and Point Zero Charge (PZC) measurements of solid PAA and PAA/SE were additionally performed to investigate the hydrogel behavior in water. Chl a molecules blended in PAA were (photo) stable and photoactive, and this latter feature was demonstrated showing that the pigment induced, when swelled in water and under irradiation, the formation of singlet oxygen (1O2), measured by direct and indirect methods.
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Fotoquimioterapia , Spirulina , Clorofila , Clorofila A , Hidrogeles , Extractos Vegetales/farmacología , PoliaminasRESUMEN
Extra virgin olive oil (EVOO) is well known for containing relevant amounts of healthy phenolic compounds. The European Food Safety Authority (EFSA) allowed a health claim for labelling olive oils containing a minimum amount of hydroxytyrosol (OHTyr) and its derivatives, including tyrosol (Tyr). Therefore, harmonized and standardized analytical protocols are required in support of an effective application of the health claim. Acid hydrolysis performed after extraction and before chromatographic analysis has been shown to be a feasible approach. Nevertheless, other fast, green, and easy methods could be useful for on-site screening and monitoring applications. In the present research, a natural deep eutectic solvent (NADES) composed of lactic acid and glucose was used to perform a liquid/liquid extraction on EVOO samples, followed by UV-spectrophotometric analysis. The spectral features of the extracts were related with the content of total OHTyr and Tyr, determined by the acid hydrolysis method. The second derivative of spectra allowed focusing on three single wavelengths (i.e., 299 nm, 290 nm, and 282 nm) significantly related with total OHTyr, total Tyr, and their sum, respectively. In particular, the sum of OHTyr and Tyr could be determined with a root mean square error of prediction of 29.5 mg kg-1, while the limits of quantitation and detection were respectively 11.8 and 4.9 mg kg-1. The proposed method, therefore, represents an easy screening tool, with the use of a green, food-derived solvent, and could be considered as an attempt to pave the way for food grade analytical chemistry.
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This study is aimed to validate water-insoluble cyclodextrin-epichlorohydrin polymer (ß-EPI) use to remove, by adsorption, sulfamethoxazole (SMX) from water and then release it via an environmentally friendly treatment so that the adsorbent can be recycled according to one of the objectives of the European Project Life "Clean up" (LIFE 16 ENV/ES/000169). SMX adsorption experiments on ß-EPI polymer in-batch were performed, varying different experimental parameters of the process, such as contact time, pH values, and so on. The adsorption process, exothermic and driven by enthalpy, occurs both through the formation of inclusion and association complexes, involves mainly hydrophobic and hydrogen bonds, has a rate-controlling step depending on both pollutant concentration and adsorbent dose and can be described by the Freundlich and Dubinin-Radushkevich models which confirm the polymer surface heterogeneity and the physical nature of the adsorption. The presence of salts gives rise to a general decrease in the SMX sorption, mainly in the case of bromide, which was used to promote the SMX desorption and regenerate the adsorbent. The overall results indicate that ß-EPI polymer is not only capable of removing SMX by adsorption with short contact times and a qmax = 10 mg/g but it is also easily regenerated using a 0.5 M solution of sodium bromide without any loss in the adsorption performance and with obvious economic and environmental advantages. The polymer as synthesized, with SMX adsorbed and regenerated was characterized by FT-IR, SEM and DSC.
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Ciclodextrinas , Contaminantes Químicos del Agua , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Sales (Química) , Espectroscopía Infrarroja por Transformada de Fourier , Sulfametoxazol , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
Chronic wounds result from the failure of the normal wound healing process. Any delay during the tissue repair process could be defined as chronic wound healing, potentially having a highly detrimental impact on human health. To face this problem, in the last years, the use of different technologies alternative to therapeutic agents is gaining more attention. The Helix aspersa snail slime-based products are increasingly being used for skin injury, thanks to their ability to make tissue repair processes faster. To date, a comprehensive overview of pure snail slime metabolome is not available. Besides, Au nanoparticles (AuNPs) technology is spreading rapidly in the medical environment, and the search for AuNPs "green" synthetic routes that involve natural products as precursor agents is demanded, alongside with a deep comprehension of the kind of species that actively take part in synthesis and product stabilization. The aim of this work is to characterize the metabolic profile of a pure snail slime sample, by an untargeted high-resolution mass spectrometry-based analysis. In addition, insights on AuNPs synthesis and stabilization by the main components of pure snail slime used to induce the synthesis were obtained. The untargeted analysis provided a large list of important classes of metabolites, that is, fatty acid derivatives, amino acids and peptides, carbohydrates and polyphenolic compounds that could be appreciated in both samples of slime, with and without AuNPs. Moreover, a direct comparison of the obtained results suggests that mostly nitrogen and sulfur-bearing metabolites take part in the synthesis and stabilization of AuNPs.
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Antiinfecciosos/química , Oro/química , Nanopartículas del Metal/química , Moco/química , Cicatrización de Heridas/efectos de los fármacos , Aminoácidos/química , Aminoácidos/metabolismo , Animales , Antiinfecciosos/farmacología , Carbohidratos/química , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Tecnología Química Verde , Humanos , Metaboloma , Péptidos/química , Péptidos/metabolismo , Polifenoles/química , Polifenoles/metabolismo , Piel , Caracoles , Espectrometría de Masas en Tándem/métodosRESUMEN
This paper accounts the first example about the development of a self-assembled supramolecular system based on the use of green-synthetized gold nanoparticles (AuNPs) and chitosan (CH), for solubilizing ellagic acid (EA) in water. AuNPs were synthetized by using Punica granatum Juice (PGJ) and, after their synthesis, in order to adsorb ellagic acid on the nanoparticles surface (AuNPs/CH/EA), the chitosan wrapping was performed (AuNPs/CH). For this purpose, chitosan having high viscosity, low and medium molecular weights were used and compared to check the best condition of work. The stability of the proposed system, before and after the addition of ellagic acid, under different conditions of work, i.e. solution pH, temperature and light irradiation were investigated demonstrating the stability of the proposed functional ingredient. The supramolecular system exhibited wide ranging properties such as antioxidant, skin lightening and sunscreen. More specifically, the % of antioxidant activity occurred around 80% and 60% from the DPPH and ABTS assays respectively; the tyrosinase inhibition was around of 50% and the Sun Protection Factor was found to be 20. Thanks to the multi-properties of the proposed functional ingredient it should exhibit several advantageous in cosmetic applications. The ingredient could be a valid alternative to the traditional nanostructured TiO2 and ZnO offering the possibility to have at the same time several properties due to the use of AuNPs (having light absorption and scattering ability, are biocompatible showing low toxicity) and EA. If these positive aspects are associated with the use of an eco-friendly and low-cost protocol for AuNPs synthesis, according to the Green Chemistry principles, a great interesting space is opened towards the study of PGJ-based AuNPs, as multifunctional platform in cosmetic.
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Antioxidantes/química , Quitosano/química , Ácido Elágico/química , Oro/química , Tecnología Química Verde/métodos , Nanopartículas del Metal/químicaRESUMEN
Seafood, a delight for many people, is sold in the market as a wide variety of products. However, seafood industries produce many by-products; for example, during the processing, the heads and shells of shellfish are generated as waste. This results in the generation of a large amount of shell waste that is accumulated over time, inducing a major environmental concern. Effective solutions for recycling shell waste should be taken into consideration, and the extraction of commercially useful substances like chitin and its derivates, such as chitosan, could be a valid solution for reducing the seafood waste's environmental impact. Thus, during this work, we propose the use of chitosan as biowaste, to induce the formation of solid films useful for decontaminating water from emerging pollutants. In particular, ketoprofen was used as a model contaminant, and a high percentage of removal, at least 90%, was obtained in a short time under our experimental conditions. Thus, a comprehensive investigation into the adsorption of ketoprofen onto chitosan film was performed, detailing the nature of the adsorption by studying the effects of pH, temperature changes, and electrolyte presence in the solutions containing the pollutant. The process was found to be pH-dependent, involving meanly electrostatic interactions between the pollutant molecules and chitosan. The endothermic character of the adsorption was inferred. The kinetics of the process was investigated, showing that the pseudo second-order kinetic model best fit the experimental data. A recycling process of the adsorbent was proposed; therefore, the adsorbed pollutant can be recovered by reusing the same adsorbent material for further consecutive cycles of adsorption without affecting the efficiency for ketoprofen removal from water.