Cláudia Nunes

Cláudia Nunes
University of Aveiro | UA · CICECO - Centre for Research in Ceramics and Composite Materials

PhD

About

140
Publications
21,061
Reads
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2,248
Citations
Additional affiliations
January 2015 - December 2017
University of Aveiro
Position
  • PostDoc Position

Publications

Publications (140)
Article
Full-text available
Carbonaceous materials derived from biomass have been used as sustainable platforms for the growth of ZnO particles aiming the production of functional composite fillers. Kidney-bean pods were pyrolyzed by applying an experimental design that demonstrates that the specific surface area (SBET) of biochar is improved with increasing pyrolysis tempera...
Article
Wildfires are a social and environmental concern to the world due to their many adverse effects, including risk to the public health and security, economic damages in prevention and fight, ecosystems pollution, land usage sustainability, and biodiversity. In the Mediterranean region, these events have increased in the last years. Although several s...
Article
Polysaccharides from pomegranate peel (Wonderful and Purple Queen® varieties) were extracted by hot water and fractionated using ethanol. Three fractions (F1-F2-F3) were obtained for each sample. Polysaccharides’ yield was higher for Purple Queen®: 13% dw. Polysaccharides of the three fractions were characterized by size exclusion chromatography (S...
Article
Microalgae are emerging as sustainable sources of a wide range of high-value compounds. However, the knowledge about microalgae polar lipids is still limited, despite their interest due to their chemical diversity and bioactivity. This study shows, for the first time, the polar lipidome of the haptophyte microalga Chrysotila pseudoroscoffensis unve...
Article
Interest in producing films from renewable and biodegradable polymers, such as polysaccharides, has increased in recent years with the aim of reducing the environmental pollution caused by petroleum-based plastics. Additionally, combining the thermoplastic property of starch with the antioxidant and antimicrobial activities of chitosan is of great...
Article
Full-text available
Carbon nanostructures are widely used as fillers to tailor the mechanical, thermal, barrier, and electrical properties of polymeric matrices employed for a wide range of applications. Reduced graphene oxide (rGO), a carbon nanostructure from the graphene derivatives family, has been incorporated in composite materials due to its remarkable electric...
Article
Impacts of nanoplastics (NPPs) on leaf decomposers and food quality were assessed. • NPPs (0-25 µg L-1) impacted leaf mass loss, fungal sporulation and abundance. • NPPs (100 nm) had a pronounced impact on food quality. • Food quality did not impact the feeding behaviour of invertebrates. • Basal trophic levels are more impacted by low concentratio...
Chapter
Seaweeds are a source of several compounds with bioactive properties. The research about these compounds has been increasing mainly to develop edible and biodegradable films to extend shelf life of food products maintaining the safety and preserving the quality of raw and pre-cooked food products, while reducing food and packaging waste. Therefore,...
Article
Hydrogels have been used in combination with cells for several biomedical and biotechnological applications. Nevertheless, the use of bulk hydrogels has exhibited severe limitations in diffusion of oxygen, nutrients, and metabolites. Here, a support for cell culture is reported where glucose is generated in situ by the own hydrogel degradation, all...
Article
Full-text available
With the knowledge of bacterial gene systems encoding proteins that target dietary carbohydrates as a source of nutrients and their importance for human health, major efforts are being made to understand carbohydrate recognition by various commensal bacteria. Here, we describe an integrative strategy that combines carbohydrate microarray technology...
Article
Full-text available
Magnetic nanoparticles (NP), such as magnetite, have been the subject of research for application in the biomedical field, especially in Magnetic Hyperthermia Therapy (MHT), a promising technique for cancer therapy. NP are often coated with different compounds such as natural or synthetic polymers to protect them from oxidation and enhance their co...
Article
Porphyridium purpureum is a red saline microalga rich in protein and floridean starch with the ability to excrete high amounts of sulfated polysaccharides (sEPS) into the growth medium. This microalga has been used for feeding fish in aquaculture. P. purpureum is easily cultivated and could change its growth rate and composition in response to envi...
Article
Mucilage extracted from chia seed (Salvia hispanica L.) (MCHs) has come to prominence in recent studies due to its attractive biological activities, improving the interest in developing Salvia hispanica as an industrial crop for sustainable source of bioactive polysaccharide. In this work, chia mucilage properties were evaluated, including physicoc...
Article
Electric field-based technologies for extraction processes have been gaining importance due to sustainability concerns. This work aims to assess the potential of ohmic heating as an efficient and feasible tool for the extraction of different biocompounds from Gracilaria vermiculophylla and its effect on the extracts' composition. Different ratios o...
Article
Acrylamide (AA) is a food contaminant in thermally processed products that is object of tight control. A simple and easy-to-apply methodology for routine monitoring of AA levels in food products could allow producers to be players in the control of their own products. In this work, a simple methodology for AA quantification without derivatization w...
Article
Full-text available
Bionanocomposite materials have been designed as a promising route to enhance biopolymer properties, especially for food packaging application. The present study reports the preparation of bionanocomposite films of alginate with different loadings of pure reduced graphene oxide (rGO) or of mixed zinc oxide-rGO (ZnO-rGO) fillers by solvent casting....
Article
Cinnamon is a spice widely used as a flavouring agent in foodstuffs. Despite its commercial availability and low cost, C. burmannii aqueous extracts obtained by decoction originate high viscous solutions (1545 cP) when compared with C. verum (51 cP), preventing its broad use by food industry. Following the hypothesis that cinnamon polysaccharides a...
Article
Full-text available
The diversity of zinc oxide (ZnO) particles and derived composites applications is highly dependent on their structure, size, morphology, defect amounts, and/or presence of dopant molecules. In this work, ZnO nanostructures are grown in situ on graphene oxide (GO) sheets by an easily implementable solvothermal method with simultaneous reduction of...
Article
The incorporation of carbon-based nanomaterials into biopolymer matrix, to provide mechanical reinforcement and to obtain electrically conductive bionanocomposites, requires the homogeneous dispersion of the fillers. Herein it is investigated the influence of surfactant structures on the dispersibility of multiwalled carbon nanotubes (MWNT) within...
Article
Full-text available
Several classes of polysaccharides have been described to have hypocholesterolemic potential, namely cholesterol bioaccessibility and bioavailability. This review will highlight the main mechanisms by which polysaccharides are known to affect cholesterol homeostasis at the intestine, namely the effect (i) of polysaccharide viscosity and its influen...
Article
Full-text available
Chitosan-genipin films have been proposed for preservation of white wine, maintaining their varietal key odorants and organoleptic characteristics of sulfur dioxide treated wines. Nevertheless, these wines showed aroma notes that slightly distinguish them. It is possible that during the contact of films with wine for at least 2 months, after fermen...
Article
A levan-type fructooligosaccharide was produced by a Paenibacillus strain isolated from Brazilian crude oil, the purity of which was 98.5% after precipitation with ethanol and dialysis. Characterization by FTIR, NMR spectroscopy, GC-FID and ESI-MS revealed that it is a mixture of linear β(2 → 6) fructosyl polymers with average degree of polymerizat...
Article
Starch, due to its thermoplastic capacity, is being explored for developing food packaging bioplastics. Nevertheless, it gives rise to brittle and hydrophilic materials. To overcome these drawbacks, in this work, the influence of potato peel phenolic extracts (PhE) on physicochemical and mechanical properties of starch-based films was studied. PhE...
Article
Full-text available
Bivalves are widely distributed through diverse habitats, including estuaries and coastal lagoons which are extremely productive ecosystems, and play important roles in trophic webs and in ecosystems’ biological processes. Bivalves, as well as other marine resources, have been a part of the humans’ diet since mankind started fishing. These resource...
Article
Longan (Dimocarpus longan Lour.) is a seasonal tropical fruit used by Chinese medicine in both fresh and dried pulp forms. Their polysaccharides have been reported to have activity. However, their composition and immune activity have not yet been disclosed. To fulfil this aim, hot water-soluble polysaccharides of fresh and dried longan pulp were fr...
Article
Full-text available
Reduced graphene oxide (rGO) is a promising graphene-based material, with transversal applicability to a wide range of technological fields. Nevertheless, the common use of efficient—but hazardous to environment and toxic—reducing agents prevents its application in biological and other fields. Consequently, the development of green reducing strateg...
Article
Full-text available
Apple concentrate juice industry generates a flavored coproduct (apple aroma) recovered in the evaporation process, which is poorly valuated due to the lack of chemical characterization and standardization. In this study, industry apple aroma was characterized, allowing for the identification of 37 compounds, the majority esters (20), alcohols (7),...
Article
There is currently a demand for flexible biomedical sensors. Characteristics as soft, thin, elastic, flexible and comfortable to the contact with skin should be matched with performance and ultimately made of sustainable, and biocompatible materials. In this work, chitosan as a flexible biodegradable polymeric matrix was combined with ferroelectric...
Article
The Front Cover shows a flexible functional biocomposite film composed of chitosan biopolymer and BaTiO3 particles, which was prepared by environmentally benign methodologies. This film is flexible, and its elasticity can be tailored by the addition of BaTiO3 particles. The dielectric permittivity increases with the barium titanate content. The evi...
Article
Food processing wastes together with the perishable foodstuff loss promote environmental and societal concerns. Food byproducts can have value as a source of functional molecules for developing active packaging without food waste, under a circular economy. Nevertheless, the often-associated extraction/chemical processes compromise the sustainabilit...
Article
Full-text available
This review aims to showcase the current use of graphene derivatives, graphene-based nanomaterials in particular, in biopolymer-based composites for food packaging applications. A brief introduction regarding the valuable attributes of available and emergent bioplastic materials is made so that their contributions to the packaging field can be unde...
Article
Full-text available
Polar lipids from microalgae have aroused greater interest as a natural source of omega-3 (n-3) polyunsaturated fatty acids (PUFA), an alternative to fish, but also as bioactive compounds with multiple applications. The present study aims to characterize the polar lipid profile of cultured microalga Emiliania huxleyi using hydrophilic interaction l...
Article
The small amount of proteins in starch-rich food industry byproducts can be an advantage to crosslink with genipin and tailor the performance of biobased films. In this work, genipin was combined with non- purified starch recovered from industrial potato washing slurries and used for films production. Starch recovered from potato washing slurries c...
Article
Agrofood byproducts may be exploited as a source of biomolecules suitable for developing bioplastic materials. In this work, the feasibility of using starch, oil, and waxes recovered from potato chips byproducts for films production was studied. The recovered potato starch-rich fraction (RPS) contained an amylopectin/amylose ratio of 2.3, gelatiniz...
Article
Genipin crosslinking increases the acidic stability of chitosan-based materials, opening an opportunity to explore new applications. In this work, the viability of using chitosan-genipin solutions on cellulose-based materials coating was studied. Non-calendered paper and cardboard were used as raw materials. Different number of chitosan-genipin coa...
Article
Isochrysis galbana (I. galbana) is a microalgae species rich in biomolecules of high commercial value and industrial relevance. Despite the numerous studies done on the extraction of different compounds from microalgae, the complete valorization of the biomass under the biorefinery concept is scarce or even inexistent. The mixture of different comp...
Article
Full-text available
Cell wall modification is integral to many plant developmental processes where cells need to separate, such as abscission. However, changes in the cell wall composition during natural fruit abscission are poorly understood. In olive (Olea europaea L), some cultivars such as ‘Picual’ undergo massive natural fruit abscission after fruit ripening. Thi...
Article
Chitosan-genipin (Ch-Ge) films have been proposed as wine preservative due to their capacity to uptake iron ions. The wine is an aqueous acidic solution of water and ethanol, whose acidity derives from tartaric acid. This acid has been shown to form negatively charged iron-tartrate complexes able to interact with the positively charged amine groups...
Article
In this work, the extraction and purification of carotenoids from the fruit Bactris gasipaes was developed. Ethanolic and aqueous solutions of ionic liquids (ILs), and surfactants were evaluated on the extraction of these pigments. Thus, we developed an optimized sustainable downstream process mediated by the best solvent with further isolation of...
Article
Sustainably made, flexible and biocompatible composites, having environmentally friendly compositions and multifunctional capabilities, are promising materials for several emerging biomedical applications. Here, the development of flexible and multifunctional chitosan-based bionanocomposites with a mixed reduced graphene oxide-iron oxide (rGO-Fe3-x...
Article
Chlorella vulgaris is a green microalga approved for human consumption with high biological value due to its high protein content and polyunsaturated fatty acids composition. Moreover, this microalga is rich in starch and structural polysaccharides that could have potential to be valued as food ingredients. To fulfill this hypothesis, starch digest...
Article
The extracellular polysaccharides produced by cyanobacteria have distinctive characteristics that make them promising for applications ranging from bioremediation to biomedicine. In this study, a sulfated polysaccharide produced by a marine cyanobacterial strain and named cyanoflan was characterized in terms of morphology, chemical composition, and...
Article
Full-text available
Commercial production of microalgal biomass for food and feed is a recent worldwide trend. Although it is common to publish nutritional data for microalgae grown at the lab-scale, data about industrial strains cultivated in an industrial setting are scarce in the literature. Thus, here we present the nutritional composition and a microbiological an...
Article
The relevance of microalgae biotechnology for producing high-value compounds with biomedical application, such as polysaccharides, has been increasing. Despite this, the knowledge about the composition and structure of microalgae polysaccharides is still scarce. In this work, water-soluble polysaccharides from Nannochloropsis oculata were extracted...
Article
MO245 exopolysaccharide (EPS) was produced in laboratory conditions from Vibrio genus microorganism isolated from bacterial mats found in Moorea Island. Its structure consists of a linear tetrasaccharide repeating unit →4)-β-D-GlcpA-(1→4)-α-D-GalpNAc-(1→3)-β-D-GlcpNAc-(1→4)-β-D-GlcpA-(1→ containing covalently-linked 5% of glucose, galactose, and rh...
Poster
Marine bivalves are distributed worldwide through diverse habitats, including estuaries andcoastal lagoons, and play important roles in the trophic webs, as they can connect primary producers to consumers, and are able to control several ecosystem’ processes, like the oxygen penetration in the sediments. As well as other seafood, bivalves are highl...
Article
Full-text available
The nutritional value and developmental variations of cultured fish were assessed for European seabass and gilthead seabream specimens reared in semi-intensive aquaculture systems in two Portuguese estuaries. Quantification of total protein and of carbohydrate and fatty acid profiles was carried out to determine differences between the composition...
Article
Chitosan is a biopolymer obtained by deacetylation of chitin extracted from sub-products of the food industry and it is rich in nitrogen content. Pyrolyzed chitosan– and chitosan-periodic mesoporous organosilica (PMO)– based porous materials with different pore structures and chemical features are prepared using different dry methods and ensuing py...
Article
Marine environments are an enormous source of materials with biological interest, such as sulphated polysaccharides, which have relevant biological activities. In this study the potential of salt pan brine water as an easily accessible source of sulphated polysaccharides was evaluated. This water revealed to have a high quantity of polymeric materi...
Article
S-metolachlor (SMOC) and terbuthylazine (TBA) are herbicides that commonly appear as active ingredients (a.i.) in the composition of plant protection products. In a previous work, experimental bioassays were performed using those chemicals to find suitable molecular biomarkers to assess its toxicity to the non-target species Scrobicularia plana. Th...
Article
Marine environments have a high quantity and diversity of sulfated polysaccharides. In coastal regions brown algae are the most abundant biomass producers and their cell walls have fucosecontaining sulfated polysaccharides (FCSP), known as fucans and/or fucoidans. These sulfated compounds have been widely researched for their biomedical properties,...
Article
High hydrostatic pressure (HHP) applied to wine in flexible plastic bottles has been studied as an enological practice for red wine aging, due to the oxidative reactions that can be promoted by this technology. To evaluate the effect of HHP on wine phenolic composition, a red wine treated with HHP was compared with different conventional wine aging...
Article
Chitosan-based functional materials are emerging for food applications. The covalent bonding of molecular entities demonstrates to enhance resistance to the typical acidity of food assigning mechanical and moisture/gas barrier properties. Moreover, the grafting to chitosan of some functional molecules, like phenolic compounds or essential oils, giv...
Poster
Full-text available
Biobased materials arise has potential solution to minimize the environmental impact caused by the disposal of synthetic polymers into landfills. Starch is an abundant thermoplastic biopolymer that allows the production of bioplastics with notable renewability and biodegradability. However, starch-based materials are hygroscopic and have poor mecha...
Poster
Full-text available
The incorporation of cinnamon cassia into food products has revealed that it has thickening properties due to the presence of soluble polysaccharides, namely highly branched arabinoxylans. The high viscosity conferred to food products by cinnamon cassia could be a technological problem in food industry. Therefore is important to have a treatment to...
Article
Chitosan-genipin films present a bluish-green color due to the conjugated double bonds formed when monomeric or dimeric genipin residues bridge chitosan. This phenomenon limits their use when colorless materials are required. In this work, a two-step oxidation strategy was developed aiming to remove color from chitosan-genipin films while preservin...
Article
Chitosan and its derivatives have been proposed for application in beverages either as natural preservatives or active packaging due to their antimicrobial and antioxidant properties. In addition, these positive charged polysaccharides have been also useful for beverages clarification and encapsulation of bioactive compounds. This review gives an o...
Article
Full-text available
The present study aims to assess the plastic response of Zostera noltei meadows traits under spatio-temporal shifts in salinity combined with sediment environmental variables (temperature; pH; loss-on-ignition (LOI); carbon (C) and nitrogen (N) pools (top 5 cm)). Z. noltei biomass, C and N pools, leaf photosynthetic performance and esterified fatty...
Article
Full-text available
The objective of this work was to characterize the thistle flower in relation to the composition of phenolic compounds and antioxidant activity, as well as the evaluation of the stability of the phenols along the digestive tract. In addition, the effect of drying temperature was evaluated and the composition in polysaccharides was also studied. For...
Chapter
During last years, scientific research on high hydrostatic pressure (HHP) as a nonthermal processing technology for preservation or aging of wine has increased substantially. HHP between 200 and 500 MPa is able to inactivate bacteria and yeasts in red and white wines, suggesting that it may be used for wine preservation. However, these treatments h...