Asymmetrical membranes have been reported as ideal wound dressings for skin regeneration. The usual methods (dry/wet-phase inversion) to produce those specific membranes are time consuming, and in majority of the cases demand the use of harmful organic solvents. In this study, supercritical carbon dioxide (scCO2)-assisted phase inversion method was applied to prepare poly(vinyl alcohol)/chitosan (PVA/CS) asymmetrical membranes. This technique can tailor the final structure of the dressing by tuning the processing conditions allowing the development of high porous materials with optimized morphology, mechanical properties and hydrophilicity. The PVA/CS dressings produced are recovered in a dry state but can form a hydrogel due to their high water uptake ability maintaining the moisturized environment needed for wound healing. The dressing presents a top thin layer of about 15 µm that allows gaseous exchange while barricading the penetration of microorganisms, and a sponge bottom layer that is able to remove excess exudates. A mathematical model based on Fick׳s second law of diffusion was developed to describe the pharmacokinetic release profile of a small drug (ibuprofen) from the swollen membrane in physiological conditions that mimic the wound. In vitro studies revealed that the dressings had excellent biocompatibility and biodegradation properties adequate for skin wound healing.

The design of small interfering RNA (siRNA) delivery materials showing efficacy in vivo is at the forefront of nanotherapeutics research. Polyurea (PURE-type) dendrimers are ‘smart’ biocompatible 3D polymers that unveil a dynamic and elegant back-folding mechanism involving hydrogen bonding between primary amines at the surface and tertiary amines and ureas at the core. Similarly, to a biological proton pump, they are able to automatically and reversibly transform their conformation in response to pH stimulus. Here, we show that PURE-G4 is a useful gene silencing platform showing no cellular toxicity. As a proof of concept we investigated the PURE-G4-siRNA dendriplex, which was shown to be an attractive platform with high transfection efficacy. The simplicity associated with the complexation of siRNA with polyurea dendrimers makes them a powerful tool for efficient cytosolic siRNA delivery.

Gold nanoparticles (AuNPs) are the most investigated nanomaterials for theragnosis applications. In a research field where live cell assays, as well as the tracking of nanomaterials into a cell's environment, are of extremely importance, water-soluble AuNPs have been intensively studied to overcome the toxic effects exerted by coatings. Unfortunately, AuNPs fluorescent tagging often fails due to self-quenching and a careful design must be carried out to maintain optoelectronic properties and biocompatibility. In this work, the synthesis of fluorescent gold nanoprobes, able to enter the cell's environment (biotags) and target the cell nucleus, was designed and the particles tracked by confocal laser scanning microscopy. The coating of AuNPs with maleimide poly(ethylene glycol) and fluorescent oligoaziridine biocompatible oligomers, resulted in robust, optically active biotags that open novel insights into cancer theragnosis.

This work proposes melanin as a new nanocarrier for pH-responsive drug release. Melanin is an abundant natural polymer that can be easily extracted from cuttlefish as nanoparticles with a suitable size range for drug delivery. However, despite its high potentiality, the application of this biopolymer in the pharmaceutical and biomedical fields is yet to be explored. Herein, melanin nanoparticles were impregnated with metronidazole, chosen as model antibiotic drug, using supercritical carbon dioxide. The drug release profile was investigated at acidic and physiologic pH, and the dominant mechanism was found to follow a non-Fickian transport. Drug release from melanin shows a strong pH dependency, which allied to its biocompatibility and lack of cytotoxicity envisages its potential application as nanocarrier in formulations for colon and intestine targeted drug delivery.

he well-known correlation between diet and physiology demonstrates the great possibilities of food to maintain or improve our health, increasing the interest in finding new products with positive physiological effects. Nowadays, one of the top research areas in Food Science and Technology is the extraction and characterization of new natural ingredients with biological activity that can be further incorporated into a functional food, contributing to consumer's well-being. Furthermore, there is a high demand for effective encapsulation methodologies to preserve all the characteristics of bioactive compounds until the physiological action site is reached. Scope and approach: In this review, the relevance of developing standard approaches for the extraction of the highly diverse bioactive compounds was described, as it defines the suitability of the following steps of separation, identification and characterization. Special attention was also dedicated to the encapsulation techniques used on hydrophilic and/or lipophilic compounds (e.g., emulsification, coacervation, supercritical fluid, inclusion complexation, emulsification-solvent evaporation and nanoprecipitation). Key findings and conclusions: Some useful conclusions regarding the selection of the best extraction methodology (Soxhlet extraction, ultrasound-assisted extraction, supercritical fluid extraction, accelerated solvent extraction, or shake extraction) were achieved, considering important aspects such as cost, required technical skills, extract integrity, green chemistry principles, solvent type, sample size, pH, temperature and pressure. In addition, this comprehensive review allowed defining the best protective approach to solve the limitations related to the extremely low absorption and bioavailability of bioactive phytochemicals, overcoming problems related to their low solubility, poor stability, low permeability and metabolic processes in the GI tract.

Bactrocera oleae (Rossi) (Diptera: Tephritidae) oviposition preference to Portuguese olive cultivars with different susceptibilities (cvs. Cobrançosa, Madural, and Verdeal Transmontana) was studied by physical and chemical parameters. Physical parameters, maturation indices, infestation levels, and fatty acids profiles were recorded.Verdeal Transmontana olives revealed higher susceptibility to olive fly attack, while cv. Cobrançosa was the less affected cultivar. A faster maturation in cv. Cobrançosa and a slower one in cv. Verdeal Transmontana were observed. Verdeal Transmontana olives reported higher volume and lower elongation, while both olives and leaves reported higher lightness, all possible attractive cues for olive fly. Fatty acids composition revealed a characteristic profile in each cultivar with constant differences during crop season.Overall, maturation process influenced biometrical data and color of olive cultivars. The slower maturation process characteristic from cv. Verdeal Transmontana could modulate the composition and physical appearance of olives, therefore interfering with olive fly females oviposition preference.

In the last years, botanicals have become increasingly available in the EU market in the form of plant food supplements (PFS), which are legally considered as foods under Directive 2002/46/EC and consequently not submitted to safety assessment prior to commercialisation. A concern related with PFS regards its botanical composition since unintentional swap of plants has been reported and also because adulterations by the substitution of higher cost botanicals for closely related, but cheaper species, can occur. Thus, there is a need for reliable methodologies to authenticate botanicals in commercialised PFS. Recently, molecular biology techniques have been suggested for this purpose. However, difficulties in recovering DNA from some PFS samples have been described (1). Thus, as part of a study for the botanical authentication of PFS, this work aimed at assessing the interference of pharmaceutical excipients on the recovery/amplification of DNA. Different PFS (tablets and capsules) were submitted to DNA extraction and amplified by real-time polymerase chain reaction (PCR) targeting universal eukaryotic and plant genes using species-specific primers for Hypericum DNA barcode loci. However, some samples gave consistently negative PCR amplifications irrespective of the target gene or DNA extraction method used, raising the question of whether some excipients could interfere with DNA extraction from PFS. To address this question, model mixtures of pharmaceutical excipients and water as control, were spiked with known amounts of template maize DNA. Each mixture was then submitted to DNA extraction and maize DNA quantified by real-time PCR. The use of either 10% talc or 0.5 % dyes (iron oxide or titanium dioxide) completely adsorbed DNA, resulting in negative PCR amplifications. The use of 1% talc or 10% silica, both frequently used as diluents in PFS, allowed recovering very low amounts of maize DNA (7.1 % and 2.5%, respectively). The results showed a clear adsorption phenomena that justify the hampering effect on DNA extraction from PFS explaining the inability of recovering DNA from some samples reported in previous works. Thus, a strategy to release plant DNA from excipients, allowing its extraction and further analysis was also assayed. Hypericum species were not detected in four PFS, although being described on the label.

Plant food supplements (PFS) have been regarded with special interest since they are concentrated sources of nutrients or other substances with a nutritional or physiological effect, contributing to a better homeostatic balance. Weight-loss PFS, one of the most consumed PFS, may include Cynara scolymus (artichoke) as an ingredient due to its antioxidant, diuretic, choleretic and hepatoprotective properties [1]. Considered as foods under the EU Directive 2002/46/EC, the PFS are not usually subjected to any safety assessment prior to their commercialisation. This can lead to adulteration issues, such as accidental swap of plants or deliberate substitution of higher cost botanicals by other similar, but cheaper species. Thus, to ensure consumer’s safety, the development of analytical methods for the correct identification of different plant species in PFS has become essential. Until now, DNA-based methods have been reported as highly appropriate tools for plant authentication [2]. The aim of this study was to discriminate C. scolymus from other Cynara spp. using real-time polymerase chain reaction (PCR) coupled to high resolution melting (HRM) analysis. For this purpose, different Cynara species (C. scolymus, C. syriaca, C. cardunculus and C. humilis) were obtained from Portuguese and French Germplasm Banks. A total of 8 PFS tablets for weight-loss containing artichoke were acquired at local herbal stores. DNA from plant material and PFS was extracted using the commercial NucleoSpin Plant II kit. Former to DNA extraction, PFS were pre-treated with a phosphate buffer 1M (pH8, 15% ethanol) to enhance the purity and quality of the extracts. The specificity and sensitivity of the designed primers targeting C. scolymus were assayed by qualitative PCR and real-time PCR with HRM analysis. The application of the specific PCR assay was successful in the detection of Cynara spp. in some of the PFS samples. The results of real-time PCR with HRM analysis showed that different Cynara spp. were included in three distinct clusters with a level of confidence above 99.4%, thus discriminating artichoke from other Cynara species. The proposed HRM analysis allowed confirming the unequivocal presence of C. scolymus in the tested PFS with high level of confidence (>98.8%). To our knowledge, this is the first successful attempt for the rapid discrimination of C. scolymus in PFS.

Game meat Alheira (Alheira de caça) sausage is a traditional fermented product typical from the Northeast region of Portugal, having bread and meats (including game) as main ingredients. It is a particularly appreciated product by consumers that commands higher prices, especially in comparison with the common Alheira produced with pork and poultry meats. Following our previous work in which several mammalian game meat species were successfully identified in game meat Alheira sausages for authentication purposes, the present work aimed at identifying game bird's species for the overall assessment of labelling compliance. For that purpose, several species-specific PCR assays targeting mitochondrial DNA for the detection of game and domestic bird's meat, namely duck, partridge, pheasant, quail, chicken and turkey were developed, optimised and applied to commercial samples of game meat Alheira for their authentication. The assays revealed a high specificity and sensitivity to detect the addition of all evaluated species down to a level of 0.01% (w/w). PCR results indicated the existence of several inconsistencies with the labelled information, namely the absence of declared game species (duck, partridge and pheasant) and the presence of undeclared poultry meat, pointing out to adulterations owing to substitution of game by domestic meat species. Since this is considered a high-valued traditional product that should be valorised and protected, this work puts in evidence the need for inspection programs to enforce regulation. © 2014 Elsevier Ltd.

O consumo de carne de cavalo depende, principalmente, dos hábitos alimentares das populações que habitam em algumas regiões. Regra geral, este animal é mais consumido nos países onde é produzido [1]. Ao longo dos tempos, o seu consumo tem variado amplamente de acordo com as dife-renças culturais e económicas da sociedade. Este animal fornece uma fonte, relativamente barata, de proteína ani-mal em países onde os cavalos são extensivamente utiliza-dos como animais de trabalho e transporte humano [2]. A textura da carne de cavalo é relativamente firma, e o seu sabor adocicado é-lhe atribuído pelo seu elevado teor em glicogénio, em comparação com outras espécies [1]. Esta carne contém um elevado teor em água, proteínas, ferro e vitaminas, que são solúveis em água. O seu menor teor em lípidos e elevado em fibras musculares e vitaminas insolú-veis em água torna-a diferente, em comparação com a carne bovina e suína [3]. Muitas vezes a ingestão de carne de ca-valo esteve associada a épocas de escassez de alimentos. Contudo, o consumo deste animal é relativamente popular nos países nórdicos e asiáticos, bem como na Itália [4]. Nos países membros da UE, o consumo médio por habitante é de apenas 0,4 kg por ano, mas devido a uma produção insu-ficiente a importação abrange 66,7% das necessidades do mercado [3].