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The effects of oxyanions selenite (SeO32-) in soils are of high concern in ecotoxicology and microbiology as they can react with mineral particles and microorganisms. This study investigated the evolution of the actinomycete Kitasatospora sp. SeTe27 in response to selenite. To this aim, we used the Adaptive Laboratory Evolution (ALE) technique, an experimental approach that mimics natural evolution and enhances microbial fitness for specific growth conditions. The original strain (wild type; WT) isolated from uncontaminated soil gave us a unique model system as it has never encountered the oxidative damage generated by the prooxidant nature of selenite. The WT strain exhibited a good basal level of selenite tolerance, although its growth and oxyanion removal capacity were limited compared to other environmental isolates. Based on these premises, the WT and the ALE strains, the latter isolated at the end of the laboratory evolution procedure, were compared. While both bacterial strains had similar fatty acid profiles, only WT cells exhibited hyphae aggregation and extensively produced membrane-like vesicles when grown in the presence of selenite (challenged conditions). Conversely, ALE selenite-grown cells showed morphological adaptation responses similar to the WT strain under unchallenged conditions, demonstrating the ALE strain improved resilience against selenite toxicity. Whole-genome sequencing revealed specific missense mutations in genes associated with anion transport and primary and secondary metabolisms in the ALE variant. These results were interpreted to show that some energy-demanding processes are attenuated in the ALE strain, prioritizing selenite bioprocessing to guarantee cell survival in the presence of selenite. The present study indicates some crucial points for adapting Kitasatospora sp. SeTe27 to selenite oxidative stress to best deal with selenium pollution. Moreover, the importance of exploring non-conventional bacterial genera, like Kitasatospora, for biotechnological applications is emphasized.
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Actinobacteria , Selenio , Ácido Selenioso/toxicidad , Selenito de Sodio/metabolismo , Selenito de Sodio/toxicidad , Actinobacteria/genética , Actinobacteria/metabolismo , Bacterias/metabolismo , Selenio/metabolismo , Oxidación-ReducciónRESUMEN
In this study, the potential of cactus pear pruning waste (CPPW) as a low-cost adsorbent biomass for phosphorus (P) removal from aqueous solutions was investigated in batch mode. Biomass samples derived from cactus pear were collected and analyzed to investigate their properties when enriched with either calcium (Ca) or iron (Fe). The examination focused on the capacity of these samples to remove P. The P removal capacities were determined to be 2.27 mg g-1, 1.33 mg g-1, and 1.87 mg g-1 for Ca2+-enriched, Fe2+-loaded, and Fe3+-loaded biomass respectively. Among the various models studied, the Langmuir isotherm model was identified as the most appropriate for accurately describing the P adsorption the enriched biomass. The kinetics of the adsorption process were analyzed by applying the pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. The pseudo-second-order model provided the best fit to the experimental data. Furthermore, the desorption and regeneration process was investigated, revealing minimal P desorption (less than 8%) from Ca or Fe-loaded biomass, indicating the strong stability of the biomass-cation-P system. The estimated cost ranged from 8 to 161 euros per tonne, with an additional 230 euros when considering the pruning costs inherent to the crop. These costs fall below the threshold (320 euros per tonne) for the economically viable P reuse at the farm level. Consequently, CPPW, when reduced to powder and loaded with ions, emerges as an affordable adsorbent with good removal performance, offering a promising avenue for direct utilization in agriculture as both soil conditioner and fertiliser.
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Tomato fruits defined as "golden" refer to a food product harvested at an incomplete ripening stage with respect to red tomatoes at full maturation. The aim of this study is to explore the putative influence of "golden tomato" (GT) on Metabolic Syndrome (MetS), especially focusing on the effects on redox homeostasis. Firstly, the differential chemical properties of the GT food matrix were characterized in terms of phytonutrient composition and antioxidant capacities with respect to red tomato (RT). Later, we assessed the biochemical, nutraceutical and eventually disease-modifying potential of GT in vivo in the high-fat-diet rat model of MetS. Our data revealed that GT oral supplementation is able to counterbalance MetS-induced biometric and metabolic modifications. Noteworthy is that this nutritional supplementation proved to reduce plasma oxidant status and improve the endogenous antioxidant barriers, assessed by strong systemic biomarkers. Furthermore, consistently with the reduction of hepatic reactive oxygen and nitrogen species (RONS) levels, treatment with GT markedly reduced the HFD-induced increase in hepatic lipid peroxidation and hepatic steatosis. This research elucidates the importance of food supplementation with GT in the prevention and management of MetS.
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The raw cladode of Opuntia ficus indica (OFI) was evaluated as a sustainable biosorbent for the removal of heavy metals (Ni, Pb, Cu, and Cd) from aqueous solutions. The functional groups of OFI were identified by employing DRIFT-FTIR and CP-MAS-NMR techniques before and after contact with the ions in an aqueous media, showing a rearrangement of the biomass structure due to the complexation between the metal and the functional groups. The adsorption process was studied in both single- and multi-component systems under batch conditions at different pHs (4.0, 5.0, and 6.0), different metal concentrations, and different biomass amounts. The results show that the raw OFI had a removal capacity at room temperature of over 80% for all metals studied after only 30 min of contact time, indicating a rapid adsorption process. Biosorption kinetics were successfully fitted by the pseudo-second-order equation, while Freundlich correctly modelled the biosorption data at equilibrium. The results of this work highlight the potential use of the untreated cladode of OFI as an economical and environmentally friendly biosorbent for the removal of heavy metals from the contaminated aqueous solution.
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Edible insects have the potential to become one of the major future foods. In fact, they can be considered cheap, highly nutritious, and healthy food sources. International agencies, such as the Food and Agriculture Organization (FAO), have focused their attention on the consumption of edible insects, in particular, regarding their nutritional value and possible biological, toxicological, and allergenic risks, wishing the development of analytical methods to verify the authenticity, quality, and safety of insect-based products. Edible insects are rich in proteins, fats, fiber, vitamins, and minerals but also seem to contain large amounts of polyphenols able to have a key role in specific bioactivities. Therefore, this review is an overview of the potential of edible insects as a source of bioactive compounds, such as polyphenols, that can be a function of diet but also related to insect chemical defense. Currently, insect phenolic compounds have mostly been assayed for their antioxidant bioactivity; however, they also exert other activities, such as anti-inflammatory and anticancer activity, antityrosinase, antigenotoxic, and pancreatic lipase inhibitory activities.
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Insectos Comestibles , Animales , Vitaminas/análisis , Antioxidantes/farmacología , Insectos/química , Polifenoles/farmacología , Polifenoles/análisisRESUMEN
The identification of a product, with its geographical origin, is a guaranty of the value of the foodstuff and protection from potential fraud. Extra virgin olive oil is produced or marketed as a single variety or a blend of two or more cultivars, often of different geographic origins. Therefore, to study a possible link between the soil and olive oil, we accounted crucial to analyse the behaviour of olive of different cultivars. We studied Rare Earth Elements (REE) amounts and their relationship to trace their distribution from soil to the olive pulp (Olea europea L.). The results obtained pointed out that the different cultivars of Olea did not drive significant differences in reciprocal ratios of REE in the uptake from the soil up to olive (except for Eu). However soil-plant Rare Earth relationships depend exclusively on the soil REE composition. This method can be the starting point to enforcing the laws, in fact, it is important to develop analytical methods to measure the authenticity of the samples, and to verify the geographical origin even when olive oil is blended.
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Even though petroleum-based plastics are advantageous in complying with the performance requirements in many applications, these are related, throughout their life cycle, to several environmental problems, including greenhouse gas emissions and persistence in marine and terrestrial environments. Therefore, the preservation of natural resources and climate change is considered worldwide, the main reason for which is necessary to reduce consumption and dependence on fossil-based materials. Biopolymers (PLA, PHAs, etc.) are examples of plastics whose use is grown exponentially over the years because of the improvements of their physical and mechanical properties using additives of various nature and depending on the scope of application. This review aims to discuss various ways of biopolymer degradation, to evaluate if they represent a new Frontier in eco-sustainability or rather a re-proposal of old problems. Related to this topic, we also have focussed our attention on the different methods for the quantitative analysis of bioplastics, or their degradation by-products, comparing and evaluating the advantages and disadvantages of each technique.
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Sustainable agricultural, food-related strategies and geographic traceability require understanding of the plant physiological response to stress potentially generated by contaminated soils. Here, we have investigated the effect of contaminated substrate on growth of Vitis vinifera L. plants analysing the distribution of full Rare Earth Elements (REE) spectra in different parts of the plant. Experiments were carried out using pristine plants growing in a handmade substrate (blank experiment) and in REE artificially-enriched soil (spiked experiment). Our results show that both plant mass and REE amount in leaves are not influenced by the substrate enrichment while roots are by one-order of magnitude enriched for three-orders of magnitude enhancement of the soil substrate. This clearly indicates that soil contamination does not significantly influence the REE amount in the aerial parts. However, the spectra of REE normalized changes when the soil is enriched. We found that Light-REE (from La to Gd) are by more than one order of magnitude enriched compared to Heavy-REE (from Tb to Lu plus Y) in spiked experiment showing the specific response of Vitis vinifera L. to the stress generated by soil contamination. We propose that REE distribution spectra is a marker of Vitis vinifera L. substrate of growth and providing a new tool for tracing the geographical origin of agri-food products.
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Metales de Tierras Raras , Contaminantes del Suelo , Vitis , Metales de Tierras Raras/análisis , Hojas de la Planta/química , Suelo , Contaminantes del Suelo/análisisRESUMEN
Citrus fruit processing wastewaters (CWWs), being rich in organic matter, may be a valuable resource for agricultural irrigation and, possibly, for the improvement of soil organic carbon (TOC). This issue is becoming crucial for soils of arid and semiarid environments increasingly experiencing water scarcity and continuous decline of TOC towards levels insufficient to sustain crop production. However, before using CWWs in agriculture their effects on the soil living component have to be clarified. Therefore, in this study we assessed the impact of CWWs on soil chemical and biochemical properties. Under laboratory conditions, lemon, orange and tangerine wastewaters were separately added to a sandy clay soil reaching 1/3, 2/3 and 3/3 of its 50% water holding capacity. Then soils were incubated for 56 days at 22-24 °C in the dark and analyzed for total and extractable organic C, microbial biomass C and N, and the main microbial groups at days 7, 28 and 56, while microbial respiration kinetics was fitted to a first-order decay model by nine distinct daily rates measurements throughout incubation. During the first 3 days following the addition of CWWs, soil pH decreased by 2-3 units; however, afterwards the soil recovered its initial pH values. Total and extractable C pools, as well as microbial biomass C and N, were stimulated by CWWS with such a stimulation depending on CWWs type and added dose. Also microbial respiration kinetics was greatly affected by CWWs, although the effects were generally ephemeral at the lowest two doses, whereas at the highest dose still persisted up to day 56, especially in orange and lemon wastewaters. The concomitant general increase of both microbial and metabolic quotients after the addition of CWWs suggested that also under stress conditions, soil microorganisms were able to immobilize C. Both bacteria and fungi were stimulated by CWWs but the latter, at the beginning of incubation, were more favored probably due to a transient soil acidification by CWWs. In conclusion, CWWs when added to a sandy-clay soil increased total and labile C pools, stimulated soil microbial activity and biomass, i.e. improved the overall biological soil fertility, thus suggesting a possible role of CWWs in sustainable agriculture. However, soil electrical conductivity has to be monitored when CWWs are applied recurrently.
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Citrus , Microbiota , Agricultura , Biomasa , Carbono , Nitrógeno/análisis , Suelo , Microbiología del Suelo , Aguas ResidualesRESUMEN
The effective control of the plum fruit moth, Grapholita funebrana (Lepidoptera: Tortricidae) still represents a difficult challenge for organic plum farming. Little information is available on the susceptibility of plum cultivars to this moth pest. We investigated the roles of several fruit parameters (i.e., shape, volume, hardness, fruit colour, and physiochemical properties) on the susceptibility of four different plum cultivars (Angeleno, Friar, President and Stanley) to G. funebrana attack. Field data demonstrated the importance of some fruit parameters (i.e., elongation index, sugar degree, titratable acidity, cover colour percentage) on susceptibility to G. funebrana infestation. Under laboratory conditions, colour and shape had a significant role in determining the time spent on false fruits, i.e., female moths preferred yellow and rounded fruits over elongated red or green fruits. Angeleno (yellow and rounded fruits) and Stanley (green and elongated fruits) were the most and least susceptible cultivars, respectively. Overall, this study adds useful knowledge about plum cultivar susceptibility to G. funebrana. Information reported here may be useful to improve integrated pest management strategies both in conventional and organic orchards because the use of less susceptible cultivars may reduce insecticidal treatments, limiting the development of resistance in target insects and the harmful side effects on beneficial species.
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We have compared the anti-proliferative activity in vitro, of R2SnGala (1-3) [Râ¯=â¯Me, n-Bu, Ph] and novel R3SnGala (4, 5) [Râ¯=â¯Me, n-Bu] with D-(+)-Galacturonic acid [HGala; Galaq-, qâ¯=â¯(2) and (1) for R2SnGala and R3SnGala, respectively] compounds, towards human tumor cell lines of intestinal carcinoma (HCT-116) and breast adenocarcinoma (MCF-7). The new synthesized 4 and 5 compounds were characterized, in solution, by 1H, 13C and 119Sn NMR, that showed that HGala acts as monoanionic moiety and evidenced the dynamic behavior of the compounds, due to inter-conversions involving the anomeric carbon atom of the ligand. Cell viability, apoptosis induction and cell cycle distribution were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay and flow cytometry, respectively. The cytotoxicity of the compounds, in the micro-submicromolar range, changed in the order of the organotin(IV) moieties, according to 5â¯>â¯3â¯>â¯2, while 1 and 4, containing MenSn(IV) (nâ¯=â¯2,3) moieties, were ineffective. Compound 5 showed peculiar cytotoxic effects. It did not cause time dependent inhibition of cell growth nor accumulated into the cells. Cell death induced by the active 2, 3, and 5, was shown to be apoptotic by measuring the exposure of phosphatidylserine to the outer membrane and the loss of mitochondrial potential. All the cytotoxic compounds induced an accumulation of cells in the subG0/G1phase, while only 2 and 3 perturbed the cell cycle confining viable cells in G0/G1phase. Finally, none of the compounds investigated affected the viability of normal intestinal or liver cells, indicating selectivity towards tumor cells.
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Adenocarcinoma , Antineoplásicos , Apoptosis/efectos de los fármacos , Neoplasias de la Mama , Ácidos Hexurónicos , Neoplasias Intestinales , Compuestos Orgánicos de Estaño , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Células CACO-2 , Supervivencia Celular/efectos de los fármacos , Células HCT116 , Ácidos Hexurónicos/química , Ácidos Hexurónicos/farmacología , Humanos , Neoplasias Intestinales/tratamiento farmacológico , Neoplasias Intestinales/metabolismo , Neoplasias Intestinales/patología , Células MCF-7 , Compuestos Orgánicos de Estaño/síntesis química , Compuestos Orgánicos de Estaño/química , Compuestos Orgánicos de Estaño/farmacologíaRESUMEN
The knowledge of a chemistry relationship between the soil and the agricultural products is an important tool for the quality assessment of food. We studied YLOID (Y, La and lanthanoids), recognized as very useful tracers due their coherent and predictable behavior, to trace and evaluate their distribution from soil to the grape in Vitis vinifera L. Because much of the world's viticulture is based on grafting, and rootstocks have proved affect vine growth, yield, fruit and wine quality, we carried out experimental trials to analyse the YLOID distribution of two different red cultivars, grafted onto six different rootstocks, on the same soil. The YLOID amounts, the relationship Heavy vs Light YLOID and the pattern of YLOID were calculated. The results showed that the different grafting combinations were not able to induce significant differences in YLOID uptake from the soil maintaining the same fingerprint (with the exception of Eu).
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Elementos de la Serie de los Lantanoides/análisis , Suelo/química , Vitis/química , Itrio/análisis , Agricultura , Frutas/química , GeografíaRESUMEN
BACKGROUND: Olive biophenols are emerging as a valued class of natural products finding practical application in the food, pharmaceutical, beverage, cosmetic and nutraceutical industries due to their powerful biological activity which includes antioxidant and antimicrobial properties. Olive mill waste water (OMWW), a by-product in olive oil manufacturing, is rich in biophenols such as hydroxytyrosol and tyrosol. The amount of biophenols depends on the cultivar, the geographical area of cultivation, and the seasonal conditions. The goal of this study was to develop a straightforward method to assess the economic value of OMWW via quantification of hydroxytyrosol and tyrosol. RESULTS: The amount of hydroxytyrosol and tyrosol phenolic compounds in the OMWW from four different cultivars grown in four different regions of Sicily was analyzed using liquid-liquid and solid-liquid analytical protocols developed ad hoc. Results showed significant differences amongst the different cultivars and their geographical origin. In all samples, the concentration of hydroxytyrosol was generally from 2 to 10 times higher than that of tyrosol. In general, the liquid-liquid extraction protocol gave higher amounts of extracted biophenols. The cultivar Cerasuola had the highest amount of both hydroxytyrosol and tyrosol. The cultivar Nocellara Etnea had the lowest content of both biophenols. CONCLUSIONS: A quick method to assess the economic value of olive mill waste water via quantification of hydroxytyrosol and tyrosol in olive phenolic enriched extracts is now available.
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In this work, an ad hoc method to identify and quantify polyphenols from caper berries was developed on high-performance liquid chromatography/electrospray ionisation source/mass spectrometry (HPLC-ESI-MS). The method was applied during fermentation carried out with Lactobacillus pentosus OM13 (Trial S) and without starter (Trial C). A total of five polyphenols were identified. All samples contained high concentrations of rutin. Epicatechin was found in untreated fruits, on the contrary quercetin was detected during fermentation. Trial S was characterised by a more rapid acidification and lower levels of spoilage microorganisms than Trial C. L. pentosus dominated among the microbial community of both trials and the highest biodiversity, in terms of strains, was displayed by Trial C. Aureobasidium pullulans was the only yeast species found. The analytical method proposed allowed a high polyphenolic compound recovery from untreated and processed caper berries in short time. The starter culture reduced the bitter taste of the final product.
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Capparis/química , Fermentación , Frutas/química , Lactobacillus/metabolismo , Polifenoles/análisis , Cromatografía Líquida de Alta Presión , Espectrometría de Masas , Rutina/análisis , LevadurasRESUMEN
In this paper, the authors provide data on a culinary-medicinal, host-specific variety of P. eryngii species-complex that is known in Italy as "cardoncello". A species description, the techniques of isolation of a new strain (C-142-c), and the preparation of the substratum are illustrated. Data on the productivity of substratum inoculated with C-142-c strain and the nutritional value of cultivated "cardoncello" mushrooms are also provided.
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Dieta , Valor Nutritivo , Pleurotus , Agaricales , Humanos , Italia , Fitoterapia , Pleurotus/clasificación , Especificidad de la EspecieRESUMEN
Very low concentrations (pg mL(-1) or sub-pg mL(-1) level) along with the high salinity are the main problems in determining trace metal contents in seawater. This problem is mainly considered for investigations of naturally occurring YLOID (Y and Lanthanides) and Zr and Hf in order to provide precise and accurate results. The inductively coupled plasma mass spectrometry (ICP-MS), both in high and low resolution, offers many advantages including simultaneous analyses of all elements and their quantitative determination with detection limits of the order of pg mL(-1). However in the analysis of YLOID in seawater, a better determination needs an efficient combination of ICP-MS measurement with a pre-concentration technique. To perform an ultra-trace analysis in seawater, we have validated an analytical procedure involving an improved modified co-precipitation on iron hydroxides to ensure the simultaneous quantitative recovery of YLOID, Zr and Hf contents with measurement by a quadrupole ICP-MS. The validity of the method was assessed through a series of co-precipitation experiments and estimation of several quality control parameters for method validation, namely working range and its linearity, detection limit, quantification limit, precision and spike recoveries, and the methodological blank choice, are introduced, evaluated and discussed. Analysis of NASS-6, is the first report on the latest seawater reference material for YLOID, hafnium and zirconium.
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Compuestos Férricos/química , Hafnio/aislamiento & purificación , Elementos de la Serie de los Lantanoides/aislamiento & purificación , Agua de Mar/química , Oligoelementos/aislamiento & purificación , Itrio/aislamiento & purificación , Circonio/aislamiento & purificación , Floculación , Límite de Detección , Control de Calidad , Espectrofotometría AtómicaRESUMEN
A fast and accurate measurement of soil carbon is needed in current scientific issues. Today there are many sensors suitable for these purposes, but choosing the appropriate sensor depends on the spatial scale at which the studies are conducted. There are few detailed studies that validate these types of measures allowing their immediate use. Here it is validated the quick use of a sensor in execution at Pantelleria, chosen for size, use and variability of the parameter measured, to give an operational tool for carbon stocks studies. The DRIFT sensor used here has been validated in the first 60 cm of the soil of the whole island, and it has shown predictivity higher than 90%.
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Polyphenols are potent antioxidants found in extra virgin olive oil (EVOO); antioxidants have been shown to reverse age- and disease-related learning and memory deficits. We examined the effects of EVOO on learning and memory in SAMP8 mice, an age-related learning/memory impairment model associated with increased amyloid-ß protein and brain oxidative damage. We administered EVOO, coconut oil, or butter to 11 month old SAMP8 mice for 6 weeks. Mice were tested in T-maze foot shock avoidance and one-trial novel object recognition with a 24 h delay. Mice which received EVOO had improved acquisition in the T-maze and spent more time with the novel object in one-trial novel object recognition versus mice which received coconut oil or butter. Mice that received EVOO had improve T-maze retention compared to the mice that received butter. EVOO increased brain glutathione levels suggesting reduced oxidative stress as a possible mechanism. These effects plus increased glutathione reductase activity, superoxide dismutase activity, and decreased tissue levels of 4-hydroxynoneal and 3-nitrotyrosine were enhanced with enriched EVOO (3 × and 5 × polyphenols concentration). Our findings suggest that EVOO has beneficial effects on learning and memory deficits found in aging and diseases, such as those related to the overproduction of amyloid-ß protein, by reversing oxidative damage in the brain, effects that are augmented with increasing concentrations of polyphenols in EVOO.
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Mantequilla , Grasas Insaturadas en la Dieta/administración & dosificación , Aprendizaje por Laberinto/fisiología , Memoria/fisiología , Aceites de Plantas/administración & dosificación , Animales , Encéfalo/metabolismo , Aceite de Coco , Ratones , Ratones Mutantes , Aceite de Oliva , Estrés Oxidativo/fisiologíaRESUMEN
The bioadhesive properties of a novel chemical hydrogel based on a polymer of protein-like structure, have been investigated by using ATR FT-IR spectroscopy. In particular, the copolymer PHG obtained by partial derivatization of PHEA with GMA was chemically crosslinked by UV irradiation at 313 nm. Crosslinked PHG was treated with water to obtain a swelled sample, named PHG-UV gel, that was brought into contact with a phosphate buffer/citric acid solution at pH 7.0 in the absence or in the presence of mucin at various concentrations (0.01, 0.1 and 1 wt.-%). Preliminary dynamic swelling studies have evidenced the occurrence of an interaction between the PHG-UV gel and the glycoprotein. This result was confirmed by ATR FT-IR measurements. A diffusion model using a solution of Ficks' second law was employed to determine the diffusion coefficient of water into PHG-UV gel as a consequence of adsorption and/or interdiffusion which occur at the PHG-UV gel/mucin solution interface. Experimental results suggest a potential use of PHG-UV gel to prepare bioadhesive devices.
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Adhesivos/química , Hidrogeles/química , Poliaminas/química , Hidrogeles/síntesis química , Hidrólisis , Fotoquímica , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Rayos UltravioletaRESUMEN
An insoluble material of polysaccharidic nature has been obtained by thermal alkali treatment of the filamentous fungus Phomopsis sp. FT-IR spectrum of the resulting material as well as its nitrogen content suggest that chitosan and glucans are the main components of the biomaterial. Information on Lewis base sites has also been obtained and used as a guideline in the evaluation of the complexing ability against a number of metal ions in aqueous media at pH in the range 4--6. Results indicate that after 24h contact time, up to 870 micromol/g of lead, 390 micromol/g of copper, 230 micromol/g of cadmium, 150 micromol/g of zinc and 110 micromol/g of nickel ions are adsorbed into the material. After approximately 10 min, about 70% of the overall adsorption process has already been completed. Adsorbed metal ions can be recovered by washing with dilute acid. Experiments have been extended to a real wastewater effluent confirming the potential of this biomaterial as a depolluting agent.