Cláudia Nunes

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

Rice husks are a low value byproduct, even though it possesses molecules with great potential, such as arabinoxylans, proteins, and silica. These molecules can be used to improve mechanical and physicochemical properties of materials for food packaging. In this work, hydrothermal treatment was used for a sustainable extraction of the valuable molec...

Damaged yacon roots, often discarded, are a rich source of sweet carbohydrates. In this context, yacon roots from the Hualqui and Crespo varieties were characterized and processed into low-calorie and low-glycemic syrups for sugar reduction in foods. Syrups were obtained using, as technological adjuvants, lemon juice and its most relevant component...

An innovative biorefinery approach was developed to obtain multiple high-value compounds from a marine bacterium. Bio-based solvents as sustainable alternatives to develop more sustainable downstream processes.

Polysaccharides offer great potential for the development of flexible and sustainable electronics thanks to their inherent biocompatibility and biodegradability. Chitosan is a promising material for biomedical applications, but its electromechanical...

Responsive magnetic nanomaterials offer significant advantages for innovative therapies, for instance, in cancer treatments that exploit on‐demand delivery on alternating magnetic field (AMF) stimulus. In this work, biocompatible magnetic bionanocomposite films are fabricated from chitosan by film casting with incorporation of magnetite nanoparticl...

In this study, the chemical composition and antioxidant profile of five edible macroalgae, Fucus vesiculosus, Palmaria palmata, Porphyra dioica, Ulva rigida, and Gracilaria gracilis, cultivated in fully controlled closed systems, were determined. Protein, carbohydrates, and fat contents ranged between 12.4% and 41.8%, 27.6% and 42.0%, and 0.1% and...

Fucoidan has been reported to present diverse bioactivities, but each extract has specific features from which a particular biological activity, such as immunomodulation, must be confirmed. In this study a commercially available pharmaceutical-grade fucoidan extracted from Fucus vesiculosus, FE, was characterized and its anti-inflammatory potential...

Chitooligosaccharides have been suggested as cholesterol reducing ingredients mostly due to their ability to sequestrate bile salts. The nature of the chitooligosaccharides-bile salts binding is usually linked with the ionic interaction. However, at physiological intestinal pH range (6.4 to 7.4) and considering chitooligosaccharides pKa, they shoul...

Brown macroalgae are an important source of polysaccharides, mainly fucose-containing sulphated polysaccharides (FCSPs), associated with several biological activities. However, the structural diversity and structure–function relationships for their bioactivities are still undisclosed. Thus, the aim of this work was to characterize the chemical stru...

Fucus vesiculosus is a brown seaweed with applications in the food, pharmaceutic, and cosmetic industries. Among its most valuable bioactive compounds are the pigment fucoxanthin and polysaccharides (e.g., fucoidans). In this study, we profiled the photosynthetic pigments and carbohydrates of F. vesiculosus from six locations along the Ílhavo Chann...

Coccolithophore microalgae, such as Emiliania huxleyi (EHUX) and Chrysotila pseudoroscoffensis (CP), are composed of calcium carbonate (CaCO3) and contain bioactive compounds that can be explored to produce sustainable food packaging. In this study, for the first time, these microalgae were incorporated as fillers in starch-based films, envisioning...

Chlorella vulgaris is a green microalga with a high chlorophyll content, representing a valuable source of green pigments for food applications. As the application of whole biomass can promote an unpleasant fish-like flavor, the use of chlorophyll extract can overcome this drawback. However, chlorophylls tend to easily degrade when out of the chlor...

Over the last years, foods are being tailored in their compositional profiles and structural properties to promote or enhance human health and well-being over and above simple nutrition. In this context, there is a need for a detailed understanding of the physical, biochemical and sensorial properties of the food categories involved since any modif...

Seaweeds are an abundant source of bioactive compounds and hydrocolloids that can be used in several industries, especially in the food industry. They can be directly consumed as a whole, used as an ingredient, or a source of several compounds that can enrich the nutrient content and sensory experience of foods. The demand for more sustainable pack...

Calcium carbonate (CaCO3) is used as a filler to improve the stiffness and processability of plastics at low cost. However, its high density limits the quantity to be used. In this work, the feasibility of using starch consolidation of eggshells-derived CaCO3 (ES) to develop lightweight fillers for low density polyethylene (LDPE)-based materials wa...

Chitosan–genipin (Ch-Ge) films have been proposed for the replacement of sulfur dioxide (SO2) in white wines preservation to circumvent the adverse health consequences caused by SO2 intake. To assess the effects of different-sized Ch-Ge films (25 and 100 cm2) on wine composition compared to SO2-treated and untreated wines, nuclear magnetic resonanc...

A handful of sea slugs of the order Sacoglossa are able to steal chloroplasts—kleptoplasts—from their algal food sources and maintain them functionally for periods ranging from several weeks to a few months. In this study, we investigated the role of kleptoplast photosynthesis on mucus production by the tropical sea slug Elysia crispata. Animals re...

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...

Chitooligosaccharides have been described as hypocholesterolemic compounds, although their structure-function relationships are not fully known. Targeting to understand their mechanisms of action, in this work, commercial chitooligosaccharides (average degree of polymerization of 10, 90% deacetylation, 20 mV surface charge potential and 2.4 cP visc...

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...

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...

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...

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...

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...

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...

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,...

Seaweeds are an abundant source of bioactive compounds and hydrocolloids that can be used in several industries, especially in the food industry. They can be directly consumed as a whole, used as an ingredient, or a source of several compounds that can enrich the nutrient content and sensory experience of foods. The demand for more sustainable pack...

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...

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...

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...

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...

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...

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...

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...

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....

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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),...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...