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1.
Plants (Basel) ; 13(13)2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38999585

RESUMEN

Solidago canadensis L. (Canadian goldenrod) is a widely distributed invasive herb from the Asteraceae family. It contains compounds that can change the soil structure and its nutritional components and thus affect indigenous species' growth, germination, and survival. Consequently, it can pose a major ecological threat to biodiversity. On the other hand, many studies show that this species, due to its chemical properties, can be used for many positive purposes in pharmacy, agriculture, medicine, cosmetic industry, etc. S. canadensis contains a diverse array of bioactive compounds that may be responsible for antioxidant, antimicrobial, and anticancer activities. Many studies have discussed the invasiveness of S. canadensis, and several chemical and genetic differences between this plant in native and introduced environments have been discovered. Previous ecological and environmental evaluations of the potential of S. canadensis as an ecosystem services provider have come out with four promising groups of its products: active extracts, essential oil, fuel, and others. Although identified, there is a need for detailed validation and prioritisation of ecosystem services. This article aims to overview the S. canadensis invasive features, emphasising chemical characterisation and its potential for providing ecosystem services. Moreover, it identifies scenarios and proposes a methodology for estimating S. canadensis use in bioeconomy.

2.
Environ Technol ; : 1-13, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783406

RESUMEN

The manufacture of foundry metal parts generates various types of mineral wastes. Studies mentioned in the literature are mainly interested in the characterisation of foundry sands and their recycling way. The other wastes (finer than sand) are not dealt and are currently stored in landfills without any recycling solution. This paper aims to fill this gap and reports the complete characterisation of foundry wastes (FW) we carried out to find a way of recycling these materials. FWs were characterised by X-ray fluorescence, X-ray diffraction, scanning electron microscopy and thermogravimetry analyses (TGAs). Leaching tests complying with the NF EN 12457-2 standard were also carried out to evaluate the pollution degree of the different waste products. The results of this work that foundries do not produce just one type of waste, but several. Five types of waste were thus analysed and the results indicated in the first step that each sand was unique and in a second one that the two foundries present a certain similarity with regard to their materials. This complete characterisation study will provide a better understanding of their chemical composition and degree of pollution, so that they can be used more effectively in cement blends, which will be the subject of the rest of this study. The reuse of FW in concrete and mortars is possible and can reduce the environmental impact caused by their storage in landfills.

3.
Food Chem ; 441: 138338, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38194794

RESUMEN

This study focuses on the characterisation and incorporation of Moringa oleifera leaf powder (MOP) from Luanda (Angola) and its extract (MOE) in fortified chocolate mousse. Dark green (DG) leaves presented superior nutritional values compared to other leaves. DG contained a higher concentration of mineral salts (10 ± 1 mg/100 g of dry leaves), phenolic compounds (267 ± 4 mg GAE/g), vitamins (1.9 ± 0.2 mg/g of dry extract) and strong antioxidant capacity (IC50, 115 ± 8 µg/mL). Therefore, DG leaves were used to fortify the chocolate mousse. The leaves were prepared in three samples: control, 2 % MOP (w/w) and 2 % MOE (v/v). Textural and rheological analysis of chocolate mousse samples revealed a pseudoplastic profile for all samples, with decreased texture attributes and viscosity due to the incorporation. The sensory evaluation demonstrated that MOP and MOE samples presented 93 % and 88 % resemblance to the original product regarding general acceptance, respectively.


Asunto(s)
Chocolate , Moringa oleifera , Extractos Vegetales , Polvos , Hojas de la Planta , Vitaminas
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 291: 122375, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36680833

RESUMEN

In this study the chemical characterisation of 24 commercial spray-paints in different colours as used in contemporary public murals, street art, and graffiti is presented. The analyses were focused on the identification of the binding media, pigments, and additives. In addition, four spray-paint samples were analysed in the form of bi-layered paint films to explore the possibility of determining the composition of multi-layered samples. The aim of the study was to provide a useful diagnostic tool for the conservation of spray-paints and the removal of overpaintings from both commissioned murals and any other form of cultural heritage. To achieve this goal, a multi-analytical approach was developed using Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) for the identification of the main binder, pigments, and fillers/extenders, while Raman spectroscopy and Scanning Electron Microscopy/Energy Dispersive X-ray Spectroscopy (SEM/EDS) were used as complementary tools for the determination of organic and inorganic pigments, and fillers. Five kinds of binders were detected in this work: (1) acrylic resins combined with nitrocellulose, (2) acrylic resins modified with styrene and combined with nitrocellulose, (3) alkyd resins modified with styrene and combined with nitrocellulose, (4) combined acrylic and alkyd resins modified with styrene and blended with nitrocellulose, and (5) combined polystyrene and acrylic resins. Also, a wide variety of organic pigments and inorganic components were detected.

5.
Front Pharmacol ; 13: 933669, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35784681

RESUMEN

Two polysaccharide fractions from Pogostemon cablin (Blanco) Benth. (P. cablin) (designated as PCB-1 and PCB2-1) were isolated by water extraction and purified by Sepharose chromatography. The chemical properties of the polysaccharides were characterised, and their antioxidant activities were evaluated. The sugar content of the crude polysaccharide (PCB), PCB-1, and PCB2-1 was 58.74, 90.23 and 88.61%, respectively. The molecular weights of PCB-1 and PCB2-1 were determined to be 97.8 and 12.8 kDa, respectively. Monosaccharide composition analysis showed that all the three polysaccharides consisted of mannose, rhamnose, galacturonic acid, galactose, glucose, and arabinose, but with varying molar ratios. The polysaccharides exhibited significantly high antioxidant activities in vitro based on the scavenging activity against hydroxyl radicals, metal ion-chelating and ferric-reducing abilities. In vivo experiments in an oxidatively damaged mice model showed that PCB-1 increased the levels of antioxidant enzymes, including superoxide dismutase, catalase, and glutathione peroxidase, and inhibited malondialdehyde formation in the serum and liver. These findings suggest that PCB-1 has significant potential as an antioxidant in functional foods.

6.
Bull Environ Contam Toxicol ; 108(3): 526-531, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33893519

RESUMEN

We report the chemical characterisation and toxic effects of municipal solid waste landfill leachates on the embryonic development of Danio rerio. The results of the Fourier transform infrared spectroscopy (FTIR) revealed the presence of nitrogen-containing groups and aromatic functional groups associated with highly toxic pollutants such as ammonia and heavy metal-humic complexes. Mortalities of up to 93 and 100% were observed in 1:64 and 1:32 landfill leachate dilutions, v/v, respectively. The hatching percentages of the fish were also severely affected, with very low percentages ranging from 0 to 33.3% for 1:32, 1:64 and 1:128 dilutions, v/v. Morphologically, a developmental arrest was evident for all treatments. This study reveals the high toxicity of landfill leachates that could contaminate the aquifer of the Yucatan Peninsula and threaten the health of living organisms.


Asunto(s)
Eliminación de Residuos , Contaminantes Químicos del Agua , Animales , Desarrollo Embrionario , México , Residuos Sólidos , Instalaciones de Eliminación de Residuos , Contaminantes Químicos del Agua/análisis , Pez Cebra
7.
EFSA J ; 19(8): e06768, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34377190

RESUMEN

The EFSA has updated the Guidance on risk assessment of the application of nanoscience and nanotechnologies in the food and feed chain, human and animal health. It covers the application areas within EFSA's remit, including novel foods, food contact materials, food/feed additives and pesticides. The updated guidance, now Scientific Committee Guidance on nano risk assessment (SC Guidance on Nano-RA), has taken account of relevant scientific studies that provide insights to physico-chemical properties, exposure assessment and hazard characterisation of nanomaterials and areas of applicability. Together with the accompanying Guidance on Technical requirements for regulated food and feed product applications to establish the presence of small particles including nanoparticles (Guidance on Particle-TR), the SC Guidance on Nano-RA specifically elaborates on physico-chemical characterisation, key parameters that should be measured, methods and techniques that can be used for characterisation of nanomaterials and their determination in complex matrices. The SC Guidance on Nano-RA also details aspects relating to exposure assessment and hazard identification and characterisation. In particular, nanospecific considerations relating to in vitro/in vivo toxicological studies are discussed and a tiered framework for toxicological testing is outlined. Furthermore, in vitro degradation, toxicokinetics, genotoxicity, local and systemic toxicity as well as general issues relating to testing of nanomaterials are described. Depending on the initial tier results, additional studies may be needed to investigate reproductive and developmental toxicity, chronic toxicity and carcinogenicity, immunotoxicity and allergenicity, neurotoxicity, effects on gut microbiome and endocrine activity. The possible use of read-across to fill data gaps as well as the potential use of integrated testing strategies and the knowledge of modes or mechanisms of action are also discussed. The Guidance proposes approaches to risk characterisation and uncertainty analysis.

8.
Artículo en Inglés | MEDLINE | ID: mdl-33848802

RESUMEN

A high-performance thin-layer chromatography with microchemical derivatization and bioassay guided detection was used for bioanalytical profiling of selected marigold plant extracts. Anisaldehyde/sulfuric acid reagent and thymol/sulfuric acid reagent were used to visualize separated components on the chromatograms. Antioxidant activity and α-amylase inhibition were assessed with 2 bioassays, DPPH assay to detect free radical scavengers and starch-iodineassay method to detect compounds that inhibit α-amylase. The highest antioxidant activity of 10.12 µg of gallic acid equivalents (GAE) per 20 µL of extract was measured in extract from Tagetes flowers and the lowest in the extract from Calendula leaves with 5.10 µg of GAE. Multiple zones of α-amylase inhibition were detected. A detailed analysis of the ATR-FTIR spectra from the bands at RF = 0.24 suggest that faradiol esters and saturated fatty acids esters, palmitic acid, myristic acid, and lauric acid are responsible for α-amylase inhibition, unsaturated fatty acids for the band at RF = 0.51 and phytoecdysteroids for the band at RF = 0.53.

9.
Sci Total Environ ; 782: 146402, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33839660

RESUMEN

Fjord systems in higher latitudes are unique coastal water ecosystems that facilitate the study of dissolved organic matter (DOM) dynamics from surface to deeper waters. The current work was undertaken in the Trondheim fjord characterized by North Atlantic waters, and compared DOM fractions from three depths - surface (3 m), intermediate (225 m) and deep (440 m) in four seasons, from late spring to winter in 2017. The high-resolution mass spectrometry data showed that DOM composition varies significantly in different seasons rather than in different depths in the fjord systems. The bacterial community composition was comparable except at spring surface and summer intermediate depths. Bacterial production was minimal below the euphotic layer, even with sufficient availability of inorganic nutrients. The bacterial production rate in the surface waters was about 7 times and over 50 times higher than that of the aphotic zone in the winter and the summer seasons, respectively. The surface heterotrophic microbial communities might have rapidly consumed the available labile DOM, with the production of more refractory DOM limiting bacterial production in aphotic layers. The greater number of CRAM-like formulas determined in the surface waters compared to other depths supports our hypothesis. The refractory DOM sequestered in the water column may either be exported into sediments attached to particulate matter and marine gels, or may escape into the atmosphere as carbon dioxide/monoxide during the photochemical oxidation pathways, suggesting that it is involved in climate change scenarios.

10.
Eur J Pharm Biopharm ; 163: 252-265, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33745980

RESUMEN

Lipid-based nanoparticles for RNA delivery (LNP-RNA) are revolutionizing the nanomedicine field, with one approved gene therapy formulation and two approved vaccines against COVID-19, as well as multiple ongoing clinical trials. As for other innovative nanopharmaceuticals (NPhs), the advancement of robust methods to assess their quality and safety profiles-in line with regulatory needs-is critical for facilitating their development and clinical translation. Asymmetric-flow field-flow fractionation coupled to multiple online optical detectors (MD-AF4) is considered a very versatile and robust approach for the physical characterisation of nanocarriers, and has been used successfully for measuring particle size, polydispersity and physical stability of lipid-based systems, including liposomes and solid lipid nanoparticles. However, the unique core structure of LNP-RNA, composed of ionizable lipids electrostatically complexed with RNA, and the relatively labile lipid-monolayer coating, is more prone to destabilization during focusing in MD-AF4 than previously characterised nanoparticles, resulting in particle aggregation and sample loss. Hence characterisation of LNP-RNA by MD-AF4 needs significant adaptation of the methods developed for liposomes. To improve the performance of MD-AF4 applied to LNP-RNA in a systematic and comprehensive manner, we have explored the use of the frit-inlet channel where, differently from the standard AF4 channel, the particles are relaxed hydrodynamically as they are injected. The absence of a focusing step minimizes contact between the particle and the membrane, reducing artefacts (e.g. sample loss, particle aggregation). Separation in a frit-inlet channel enables satisfactory reproducibility and acceptable sample recovery in the commercially available MD-AF4 instruments. In addition to slice-by-slice measurements of particle size, MD-AF4 also allows to determine particle concentration and the particle size distribution, demonstrating enhanced versatility beyond standard sizing measurements.


Asunto(s)
Portadores de Fármacos/química , Lípidos/química , Nanopartículas/química , ARN/administración & dosificación , ARN/química , Fraccionamiento de Campo-Flujo/métodos , Humanos , Nanomedicina/métodos , Tamaño de la Partícula , Preparaciones Farmacéuticas/administración & dosificación , Preparaciones Farmacéuticas/química
11.
Small ; 17(15): e2004630, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33475244

RESUMEN

Would an engineered nanomaterial (ENM) still have the same identity once it reaches a secondary target tissue after a journey through several physiological compartments? Probably not. Does it matter? ENM pre-treatments may enhance the physiological relevance of in vitro testing via controlled transformation of the ENM identity. The implications of material transformation upon reactivity, cytotoxicity, inflammatory, and genotoxic potential of Ag and SiO2 ENM on advanced gastro-intestinal tract cell cultures and 3D liver spheroids are demonstrated. Pre-treatments are recommended for certain ENM only.


Asunto(s)
Nanoestructuras , Dióxido de Silicio , Técnicas In Vitro , Hígado
12.
Sci Total Environ ; 749: 141413, 2020 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-32814204

RESUMEN

Accounting for up to three quarters of the wastewater volume resulting from domestic activities but containing only a third of its organic content, greywater is seen as an alternative water source for non-potable reuse. This unique study explores the question whether consumers' product selection could affect the treatability and reuse of bathroom greywater. Fifty five personal care and household products (PCHP) were analysed for their effects on a range of water quality parameters including their aquatic and soil toxicity using Microtox® and MicroResp™. The organic content of these PCHPs varied considerably, not only from one category to another (0.2 gTOC.L-1 for hair conditioners to 2.7 gTOC.L-1 for toothpastes), but also within each category (0.1 gTOC.L-1 to 3.6 gTOC.L-1 amongst the shampoos). As expected, the PCHPs' macronutrient content was low, suggesting some limitation towards biological treatment of bathroom greywater. Regarding the impact of product selection on toxicity towards aquatic and soil microorganisms, the results revealed a higher sensitivity of Vibrio fischeri to the individual PCHPs than the MicroResp™ soil microorganisms. In the latter case, 75% of the products caused a stimulation response from the microorganisms although some decreases in basal respiration were observed for specific PCHPs within product categories. However, based solely on MicroResp™, the short-term discharge of treated bathroom greywater, regardless of consumer product selection, is unlikely to have a negative impact on soil microbial activity. Overall, the work has demonstrated the importance of consumer choice on the pollution load and treatability of greywater. However, no clear link between greywater characteristics and factors that normally determine consumer product selection (branding, type) were identified. This means it is not currently possible for consumers to actively manage the issue through choice such that process designers and technology developers must ensure technologies are sufficiently robust to manage the potential variations that could occur.


Asunto(s)
Cosméticos , Contaminantes Químicos del Agua , Suelo , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
13.
Chemosphere ; 241: 124964, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31604195

RESUMEN

Around former glass factories in south eastern Sweden, there are dozens of dumps whose radioactivity and physico-chemical properties were not investigated previously. Thus, radiometric and physico-chemical characteristics of waste at Madesjö glass dump were studied to evaluate pre-recycling storage requirements and potential radiological and environmental risks. The material was sieved, hand-sorted, leached and scanned with X-Ray Fluorescence (XRF). External dose rates and activity concentrations of Naturally Occurring Radioactive Materials from 238U, 232Th series and 40K were also measured coupled with a radiological risk assessment. Results showed that the waste was 95% glass and dominated by fine fractions (<11.3 mm) at 43.6%. The fine fraction had pH 7.8, 2.6% moisture content, 123 mg kg-1 Total Dissolved Solids, 37.2 mg kg-1 Dissolved Organic Carbon and 10.5 mg kg-1 fluorides. Compared with Swedish EPA guidelines, the elements As, Cd, Pb and Zn were in hazardous concentrations while Pb leached more than the limits for inert and non-hazardous wastes. With 40K activity concentration up to 3000 Bq kg-1, enhanced external dose rates of 40K were established (0.20 µSv h-1) although no radiological risk was found since both External Hazard Index (Hex) and Gamma Index (Iγ) were <1. The glass dump needs remediation and storage of the waste materials under a safe hazardous waste class 'Bank Account' storage cell as a secondary resource for potential future recycling.


Asunto(s)
Fenómenos Químicos , Vidrio/análisis , Contaminantes Radiactivos/análisis , Residuos Radiactivos/análisis , Residuos/análisis , Residuos Peligrosos , Radioisótopos de Potasio/análisis , Reciclaje , Espectrometría por Rayos X , Suecia , Torio/análisis , Uranio/análisis
14.
Int J Pharm ; 577: 118901, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31846726

RESUMEN

In dry powder inhalation (DPI), larger carrier particles, typically lactose, are blended with micronised active pharmaceutical ingredient (API) particles to improve handling, processability and inhalable fraction. Alternative carrier materials were researched for years, but did not enter the market yet. In this study, a common lactose carrier for DPI formulations and a spray granulated mannitol carrier were compared to evaluate if the particle engineered mannitol can be considered a serious alternative. Blends with five different API concentrations (0.1 to 4%) were prepared with two APIs. Physical carrier and blend characterisation regarding particle size, morphology, density, shear cell testing and dosing behaviour were performed. Aerodynamic assessment was done using two different inhaler devices (one capsule-based inhaler and one reservoir-based inhaler). In addition, the influence of different flow rates was examined. Results indicated that uniform dosing in metered mass and delivered dose over this API concentration range was achieved due to good flowability of the blends. Furthermore, linear dose delivery could be seen over the added API concentrations. Impaction analysis showed that the respirable fractions of mannitol blends were comparable (for salbutamol sulphate blends) or higher (for budesonide blends) than with a standard lactose carrier.


Asunto(s)
Administración por Inhalación , Budesonida/administración & dosificación , Portadores de Fármacos , Inhaladores de Polvo Seco/estadística & datos numéricos , Lactosa/administración & dosificación , Manitol/administración & dosificación , Fenómenos Mecánicos , Albuterol/administración & dosificación , Tamaño de la Partícula
15.
J Sci Food Agric ; 98(3): 1088-1094, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28722782

RESUMEN

BACKGROUND: In this work different formulations of blueberry liquor were tested and characterised based on their physico-chemical and sensory characteristics. RESULTS: Three factors were evaluated: the distillate used to produce the liquor (wine spirit or grape marc spirit); the sweetener (white sugar or honey) and the fruit quantity (two doses). For each liquor, pH, total acidity, dry soluble solids content, dry extract, alcoholic strength, reducing sugars, colour intensity, methanol content, acetaldehyde and fusel alcohols were determined. Sensory tests were carried out with a trained panel. CONCLUSION: The three factors studied significantly influenced the physico-chemical features of the liquors, being the quantity of fruit the most discriminating factor, except for the volatile compounds which were mainly influenced by the distillate. As regards the sensory analysis, it was found that the most appreciated liquor was that prepared with wine spirit, sugar and a lower dose of blueberry, and the less appreciated formulation was the one made with grape marc spirit, honey and a lower quantity of blueberry. © 2017 Society of Chemical Industry.


Asunto(s)
Bebidas Alcohólicas/análisis , Arándanos Azules (Planta)/química , Manipulación de Alimentos/métodos , Adulto , Arándanos Azules (Planta)/microbiología , Destilación , Femenino , Fermentación , Frutas/química , Frutas/microbiología , Humanos , Masculino , Persona de Mediana Edad , Edulcorantes/análisis , Gusto , Vitis/química , Vitis/microbiología , Compuestos Orgánicos Volátiles/análisis , Levaduras/metabolismo , Adulto Joven
16.
Eur J Pharm Biopharm ; 114: 119-134, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28126392

RESUMEN

This study was aimed at preparing, characterising and evaluating in situ gel formulations based on a blend of two hydrophilic polymers i.e. poloxamer 407 (P407) and poloxamer 188 (P188) for a sustained ocular delivery of ketorolac tromethamine (KT). Drug-polymer interaction studies were performed using DSC and FT-IR. The gelation temperature (Tsol-gel), gelation time, rheological behaviour, mucoadhesive characteristics of these gels, transcorneal permeation and ocular irritation as well as toxicity was investigated. DSC and FT-IR studies revealed that there may be electrostatic interactions between the drug and the polymers used. P188 modified the Tsol/gel of P407 bringing it close to eye temperature (35°C) compared with the formulation containing P407 alone. Moreover, gels that comprised P407 and P188 exhibited a pseudoplastic behaviour at different concentrations. Furthermore, mucoadhesion study using mucin discs showed that in situ gel formulations have good mucoadhesive characteristics upon increasing the concentration of P407. When comparing formulations PP11 and PP12, the work of adhesion decreased significantly (P<0.001) from 377.9±7.79mNmm to 272.3±6.11mNmm. In vitro release and ex vivo permeation experiments indicated that the in situ gels were able to prolong and control KT release as only 48% of the KT released within 12h. In addition, the HET-CAM and BCOP tests confirmed the non-irritancy of KT loaded in situ gels, and HET-CAM test demonstrated the ability of ocular protection against strongly irritant substances. MTT assay on primary corneal epithelial cells revealed that in situ gel formulations loaded with KT showed reasonable and acceptable percent cell viability compared with control samples.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/farmacocinética , Ketorolaco Trometamina/administración & dosificación , Ketorolaco Trometamina/farmacocinética , Poloxámero/química , Animales , Antiinflamatorios no Esteroideos/efectos adversos , Bovinos , Córnea/efectos de los fármacos , Composición de Medicamentos , Excipientes , Geles , Ketorolaco Trometamina/efectos adversos , Absorción Cutánea , Temperatura , Adhesivos Tisulares
17.
Part Fibre Toxicol ; 13(1): 50, 2016 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-27613375

RESUMEN

BACKGROUND: The rapid production and incorporation of engineered nanomaterials into consumer products alongside research suggesting nanomaterials can cause cell death and DNA damage (genotoxicity) makes in vitro assays desirable for nanosafety screening. However, conflicting outcomes are often observed when in vitro and in vivo study results are compared, suggesting more physiologically representative in vitro models are required to minimise reliance on animal testing. METHOD: BASF Levasil® silica nanoparticles (16 and 85 nm) were used to adapt the 3D reconstructed skin micronucleus (RSMN) assay for nanomaterials administered topically or into the growth medium. 3D dose-responses were compared to a 2D micronucleus assay using monocultured human B cells (TK6) after standardising dose between 2D / 3D assays by total nanoparticle mass to cell number. Cryogenic vitrification, scanning electron microscopy and dynamic light scattering techniques were applied to characterise in-medium and air-liquid interface exposures. Advanced transmission electron microscopy imaging modes (high angle annular dark field) and X-ray spectrometry were used to define nanoparticle penetration / cellular uptake in the intact 3D models and 2D monocultured cells. RESULTS: For all 2D exposures, significant (p < 0.002) increases in genotoxicity were observed (≥100 µg/mL) alongside cell viability decreases (p < 0.015) at doses ≥200 µg/mL (16 nm-SiO2) and ≥100 µg/mL (85 nm-SiO2). In contrast, 2D-equivalent exposures to the 3D models (≤300 µg/mL) caused no significant DNA damage or impact on cell viability. Further increasing dose to the 3D models led to probable air-liquid interface suffocation. Nanoparticle penetration / cell uptake analysis revealed no exposure to the live cells of the 3D model occurred due to the protective nature of the skin model's 3D cellular microarchitecture (topical exposures) and confounding barrier effects of the collagen cell attachment layer (in-medium exposures). 2D monocultured cells meanwhile showed extensive internalisation of both silica particles causing (geno)toxicity. CONCLUSIONS: The results establish the importance of tissue microarchitecture in defining nanomaterial exposure, and suggest 3D in vitro models could play a role in bridging the gap between in vitro and in vivo outcomes in nanotoxicology. Robust exposure characterisation and uptake assessment methods (as demonstrated) are essential to interpret nano(geno)toxicity studies successfully.


Asunto(s)
Pruebas de Micronúcleos , Modelos Biológicos , Nanopartículas/toxicidad , Piel/efectos de los fármacos , Humanos , Técnicas In Vitro , Microscopía Electrónica de Transmisión
18.
Food Chem ; 194: 650-8, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26471604

RESUMEN

Pressurised water extraction (PWE) of polysaccharides from blackcurrant fruits was investigated using a response surface methodology (RSM). The optimal conditions for PWE were: time 51min, pressure 1.6MPa, and temperature 52°C. Under these conditions, the experimental yield of Ribes nigrum L. polysaccharides (RNLP) was 11.68±0.12%, which closely agreed with the predicted value (11.77%). After preliminary purification with D4006 macroporous resin, RNLP I was obtained and its chemical characterisation was undertaken by GC, HPLC, and IR spectroscopy. RNLP I was composed of rhamnose, arabinose, xylose, mannose, galactose, and glucose with a molar ratio of 2.89:14.82:1.02:1.00:2.53:6.39 and its molecular weight was 1.49×10(4)kDa. The antioxidant activity of RNLP I was evaluated by free radical scavenging assays and a reducing power assay in vitro. RNLP I showed strong DPPH and superoxide radical scavenging activities and reducing power.


Asunto(s)
Extractos Vegetales/química , Polisacáridos/química , Presión , Ribes , Agua/química , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Peso Molecular , Monosacáridos , Oxidación-Reducción , Espectrofotometría Infrarroja , Temperatura
19.
Waste Manag ; 41: 12-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25882791

RESUMEN

The development and deployment of thermochemical waste-to-energy systems requires an understanding of the fundamental characteristics of waste streams. Despite Australia's growing interest in gasification of waste streams, no data are available on their thermochemical properties. This work presents, for the first time, a characterisation of green waste and municipal solid waste in terms of chemistry and energy content. The study took place in Brisbane, the capital city of Queensland. The municipal solid waste was hand-sorted and classified into ten groups, including non-combustibles. The chemical properties of the combustible portion of municipal solid waste were measured directly and compared with calculations made based on their weight ratios in the overall municipal solid waste. The results obtained from both methods were in good agreement. The moisture content of green waste ranged from 29% to 46%. This variability - and the tendency for soil material to contaminate the samples - was the main contributor to the variation of samples' energy content, which ranged between 7.8 and 10.7MJ/kg. The total moisture content of food wastes and garden wastes was as high as 70% and 60%, respectively, while the total moisture content of non-packaging plastics was as low as 2.2%. The overall energy content (lower heating value on a wet basis, LHVwb) of the municipal solid waste was 7.9MJ/kg, which is well above the World Bank-recommended value for utilisation in thermochemical conversion processes.


Asunto(s)
Fuentes Generadoras de Energía , Eliminación de Residuos/métodos , Residuos Sólidos/análisis , Queensland
20.
Carbohydr Polym ; 117: 364-369, 2015 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-25498647

RESUMEN

Extracted pectins have been utilised in a number of applications in both the food and pharmaceutical industries where they are generally used as gelling agents, thickeners and stabilisers, although a number of pectins have been shown to be bioactive. These functional properties will depend upon extraction conditions. A statistical experimental design approach was used to study the effects of extraction conditions pH, time and temperature on pectins extracted from Cucumis melo Inodorus. The results show that the chemical composition is very sensitive to these conditions and that this has a great influence on for example the degree of branching. Higher temperatures, lower pHs and longer extraction times lead to a loss of the more acid labile arabinofuranose residues present on the pectin side chain. The fitting of regression equations relating yield and composition to extraction conditions can therefore lead to tailor-made pectins for specific properties and/or applications.


Asunto(s)
Cucumis melo/química , Extracción Líquido-Líquido/métodos , Pectinas/química
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