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1.
Compr Rev Food Sci Food Saf ; 21(1): 453-476, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34773427

RESUMO

The wastes generated during the olive oil extraction process, even if presenting a negative impact for the environment, contain several bioactive compounds that have considerable health benefits. After suitable extraction and purification, these compounds can be used as food antioxidants or as active ingredients in nutraceutical and cosmetic products due to their interesting technological and pharmaceutical properties. The aim of this review, after presenting general applications of the different types of wastes generated from this industry, is to focus on the olive pomace produced by the two-phase system and to explore the challenging applications of the main individual compounds present in this waste. Hydroxytyrosol, tyrosol, oleuropein, oleuropein aglycone, and verbascoside are the most abundant bioactive compounds present in olive pomace. Besides their antioxidant activity, these compounds also demonstrated other biological properties such as antimicrobial, anticancer, or anti-inflammatory, thus being used in formulations to produce pharmaceutical and cosmetic products or in the fortification of food. Nevertheless, it is mandatory to involve both industries and researchers to create strategies to valorize these byproducts while maintaining environmental sustainability.


Assuntos
Olea , Antioxidantes , Resíduos Industriais/análise , Azeite de Oliva , Extratos Vegetais
2.
Int J Mol Sci ; 22(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805556

RESUMO

Biological therapies, such as recombinant proteins, are nowadays amongst the most promising approaches towards precision medicine. One of the most innovative methodologies currently available aimed at improving the production yield of recombinant proteins with minimization of costs relies on the combination of in silico studies to predict and deepen the understanding of the modified proteins with an experimental approach. The work described herein aims at the design and production of a biomimetic vector containing the single-chain variable domain fragment (scFv) of an anti-HER2 antibody fragment as a targeting motif fused with HIV gp41. Molecular modeling and docking studies were performed to develop the recombinant protein sequence. Subsequently, the DNA plasmid was produced and HEK-293T cells were transfected to evaluate the designed vector. The obtained results demonstrated that the plasmid construction is robust and can be expressed in the selected cell line. The multidisciplinary integrated in silico and experimental strategy adopted for the construction of a recombinant protein which can be used in HER2+-targeted therapy paves the way towards the production of other therapeutic proteins in a more cost-effective way.


Assuntos
Engenharia de Proteínas/métodos , Proteínas Recombinantes/genética , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/genética , Simulação por Computador , Vetores Genéticos , Células HEK293 , Proteína gp41 do Envelope de HIV/química , Proteína gp41 do Envelope de HIV/genética , Humanos , Simulação de Acoplamento Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Trastuzumab/genética
3.
Food Microbiol ; 98: 103782, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875210

RESUMO

Electrons with energies of 300 keV or lower have the potential to decontaminate the surfaces of various types of food products with minimal loss of quality. The aim of the present work was to determine the thickness of the layer inhabited by microorganisms. The food samples tested were black and white pepper irradiated with 200 keV, 230 keV, 300 keV and 9 MeV beams of electron energy. To determine the depth from the surface which can be inhabited by microorganisms two approaches were tested. The methods used were based on the application of different microbiological recovery techniques and the microbial effectiveness of the irradiation process depending on the energy of the electron beam. It was observed that the layer which microorganisms may contaminate differed for the tested samples it was estimated as being below 100 µm thick for white pepper and about 200 µm for black pepper. The penetration ability was significant in experiments performed, and as a result the electron beam at the lowest levels tested (200 and 230 keV) was found to be insufficient to effectively decontaminate the black pepper samples. The beam of energy 300 keV was found to have a similar microbial inactivation effect as the high energy electron beam (9 MeV).


Assuntos
Bactérias/efeitos da radiação , Contaminação de Alimentos/prevenção & controle , Irradiação de Alimentos/métodos , Piper nigrum/microbiologia , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Elétrons , Contaminação de Alimentos/análise , Irradiação de Alimentos/instrumentação , Viabilidade Microbiana/efeitos da radiação , Piper nigrum/efeitos da radiação , Verduras/microbiologia , Verduras/efeitos da radiação
4.
Environ Pollut ; 273: 116417, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33465652

RESUMO

A wider characterization of indoor air quality during sleep is still lacking in the literature. This study intends to assess bioburden before and after sleeping periods in Portuguese dwellings through active methods (air sampling) coupled with passive methods, such as electrostatic dust cloths (EDC); and investigate associations between before and after sleeping and bioburden. In addition, and driven by the lack of information regarding fungi azole-resistance in Portuguese dwellings, a screening with supplemented media was also performed. The most prevalent genera of airborne bacteria identified in the indoor air of the bedrooms were Micrococcus (41%), Staphylococcus (15%) and Neisseria (9%). The major indoor bacterial species isolated in all ten studied bedrooms were Micrococcus luteus (30%), Staphylococcus aureus (13%) and Micrococcus varians (11%). Our results highlight that our bodies are the source of the majority of the bacteria found in the indoor air of our homes. Regarding air fungal contamination, Chrysosporium spp. presented the highest prevalence both in after the sleeping period (40.8%) and before the sleeping period (28.8%) followed by Penicillium spp. (23.47% morning; 23.6% night) and Chrysonilia spp. (12.4% morning; 20.3% night). Several Aspergillus sections were identified in air and EDC samples. However, none of the fungal species/strains (Aspergillus sections Fumigati, Flavi, Nidulantes and Circumdati) were amplified by qPCR in the analyzed EDC. The correlations observed suggest reduced susceptibility to antifungal drugs of some fungal species found in sleeping environments. Toxigenic fungal species and indicators of harmful fungal contamination were observed in sleeping environments.

5.
Biomolecules ; 9(11)2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31694351

RESUMO

Human epidermal growth factor 2 (HER2) is a ligand-free tyrosine kinase receptor of the HER family that is overexpressed in some of the most aggressive tumours. Although it is known that HER2 dimerization involves a specific region of its extracellular domain, the so-called "dimerization arm", the mechanism of dimerization inhibition remains uncertain. However, uncovering how antibody interactions lead to inhibition of HER2 dimerization is of key importance in understanding its role in tumour progression and therapy. Herein, we employed several computational modelling techniques for a molecular-level understanding of the interactions between HER and specific anti-HER2 antibodies, namely an antigen-binding (Fab) fragment (F0178) and a single-chain variable fragment from Trastuzumab (scFv). Specifically, we investigated the effects of antibody-HER2 interactions on the key residues of "dimerization arm" from molecular dynamics (MD) simulations of unbound HER (in a total of 1 µs), as well as ScFv:HER2 and F0178:HER2 complexes (for a total of 2.5 µs). A deep surface analysis of HER receptor revealed that the binding of specific anti-HER2 antibodies induced conformational changes both in the interfacial residues, which was expected, and in the ECDII (extracellular domain), in particular at the "dimerization arm", which is critical in establishing protein-protein interface (PPI) interactions. Our results support and advance the knowledge on the already described trastuzumab effect on blocking HER2 dimerization through synergistic inhibition and/or steric hindrance. Furthermore, our approach offers a new strategy for fine-tuning target activity through allosteric ligands.


Assuntos
Anticorpos/farmacologia , Receptor ErbB-2/química , Receptor ErbB-2/metabolismo , Humanos , Fragmentos Fab das Imunoglobulinas/farmacologia , Modelos Moleculares , Simulação de Dinâmica Molecular , Multimerização Proteica/efeitos dos fármacos , Trastuzumab/farmacologia
6.
Food Chem ; 278: 760-766, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30583439

RESUMO

Mushroom production and consumption is increasing, but high perishability still represents a major commercial drawback. Besides increasing the product shelf-life, conservation processes should be innocuous to consumers. Therefore, the effects of gamma and electron beam radiation on chemical and nutritional composition of fresh samples of Agaricus bisporus Portobello (a highly commercialized species) were assessed. Mushrooms were irradiated at 1, 2 or 5 kGy, and analyzed at different times (0, 4 and 8 days). In general, irradiation type had higher effect than irradiation dose. Gamma irradiation was associated with higher contents in sugars and ergosterol, while the 5 kGy dose, independently of irradiation source, was linked with higher protein levels. Nonetheless, irradiation might represent an effective preservation methodology for Portobello mushrooms, as it was effective in maintaining their chemical profiles (except for minor organic acids and saturated fatty acids) throughout the assayed time intervals.


Assuntos
Agaricus , Irradiação de Alimentos/métodos , Agaricus/química , Agaricus/efeitos da radiação , Relação Dose-Resposta à Radiação , Elétrons , Ergosterol/análise , Armazenamento de Alimentos/métodos , Raios gama , Proteínas de Plantas/análise , Fatores de Tempo
7.
Food Res Int ; 111: 272-280, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30007686

RESUMO

The preserving capacity of gamma radiation (10 kGy) on the chemical, nutritional and antioxidant components of Aloysia citrodora Paláu, Melissa officinalis L., Melittis melissophyllum L. and Mentha piperita L., stored for 12 and 18 months, was evaluated. Despite the maintenance of the main characteristics during the first 12 months of storage, the additional 6 months induced several significant changes in individual compounds. In general, the analyzed species reacted dissimilarly throughout time, but it was possible to verify that the fatty acids, tocopherols and antioxidant capacity presented the most significant changes after 18 months of storage, inclusively in samples submitted to gamma radiation. In fact, the applied treatment (10 kGy) did not seem to be effective to prevent the decrease of free sugars, organic acids and tocopherols, especially considering the 18 months period. On the other hand, the evolution in color parameters indicated a greener color (yet slightly more yellow) among irradiated samples. Likewise, gamma radiation had a positive effect on oleic acid, ß-carotene bleaching inhibition (in infusions), DPPH scavenging activity and reducing power (in methanolic extracts). Nevertheless, it might be generally concluded that gamma radiation is less suitable than electron-beam to maintain the characteristics of dried herbs during extended storage periods.


Assuntos
Antioxidantes/efeitos da radiação , Irradiação de Alimentos/métodos , Armazenamento de Alimentos/métodos , Lamiaceae/efeitos da radiação , Valor Nutritivo , Verbenaceae/efeitos da radiação , Antioxidantes/química , Armazenamento de Alimentos/estatística & dados numéricos , Raios gama , Lamiaceae/química , Melissa/química , Melissa/efeitos da radiação , Mentha piperita/química , Mentha piperita/efeitos da radiação , Tempo , Verbenaceae/química
8.
Water Sci Technol ; 77(1-2): 456-466, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29377830

RESUMO

The adsorption of four phenolic compounds (gallic acid, protocatechuic acid, vanillic acid and syringic acid) is investigated using a synthesized mesoporous carbon on both single and multi-component synthetic solutions. Some correlation of the adsorption capacity of the carbon and the nature of adsorbate could be made, except for gallic acid whose concentration decrease seems to be not exclusively due to adsorption but also to polymerization reaction. In the multi-component mixture, negative effects in the adsorption capacity are observed probably due to competition for the active centers of the adsorbent surface. In desorption studies, ethanol presents better performance than water and acetonitrile. Vanillic acid is the compound with the higher adsorption and interestingly it is then possible to desorb a relatively high amount of it from the adsorbent, which may represent a possibility for a selective recovery of vanillic acid. These results present a potential way to treat the wastewater from the cork industry.


Assuntos
Carvão Vegetal/química , Formaldeído/química , Fenóis/análise , Resorcinóis/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Modelos Teóricos , Quercus/química , Soluções , Águas Residuárias/química
9.
Environ Technol ; 39(7): 873-877, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28357925

RESUMO

Slaughterhouse industry produces large volumes of polluted wastewater, which cause negative impacts on the environment. The objective of this study was to assess the effect of electron-beam irradiation on the ecotoxicity of slaughterhouse effluents with absorbed doses up to 35 kGy. Two acute toxicity assays were applied to evaluate the efficiency of irradiation onto toxicity of wastewater. The exposed living-organisms were a luminescent bacteria Vibrio fischeri, and a freshwater microcrustacean Daphnia similis. Also, the total organic carbon was analysed in order to determine any possible organic carbon removal after irradiation. The ecotoxicological results evidenced that both living-organisms were suitable for the measurements. Therefore, the results demonstrated the toxicity of the effluent and its similarity for both organisms as well as the potential of radiation to reduce these effects. The 35 kGy dose was very effective for reducing toxic effects of slaughterhouse wastewater for daphnids suggesting that ionizing radiation could be used as a tool for removing toxic charge of such effluents. The type of contamination presented by the effluent justify the needs for alternatives of treatment.


Assuntos
Matadouros , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri , Animais , Daphnia , Águas Residuárias
10.
J Food Sci Technol ; 53(7): 2943-2956, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27765965

RESUMO

The effects of conventional and inert-gas enriched atmospheres, as well as those caused by different γ-irradiation doses, on buckler sorrel (Rumex induratus) leaves quality were evaluated and compared after 12 days of storage at 4 °C. The green colour of the abaxial surface of the leaves was relatively stable, as well as the carbohydrates content and the calorific value. The storage time decreased the amounts of fructose, glucose, trehalose, α-tocopherol, and ß-tocopherol and increased the levels of total organic acids and δ-tocopherol. The total tocopherols content was higher in air-packaged non-irradiated leaves, antioxidant compounds that may have contributed to the preservation of polyunsaturated fatty acids (PUFA). Some antioxidant properties were also favoured during storage. It was found that the overall postharvest quality of buckler sorrel leaves is better maintained with the argon-enriched atmospheres, while the 6 kGy dose was a suitable option to preserve PUF+A during cold storage. This study highlights the suitability of the applied postharvest treatments and the interest to include buckler sorrel leaves in contemporary diets.

11.
Food Chem ; 206: 50-8, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27041297

RESUMO

The suitability of gamma irradiation (1, 2 and 5kGy) for preserving quality parameters of fresh-cut watercress (Nasturtium officinale R. Br.) during storage at 4±1°C for 7d was investigated. The storage time decreased the protein content and the main carbohydrates, and increased the levels of malic and fumaric acids, sucrose and mono- and polyunsaturated fatty acids (MUFA and PUFA). The different irradiation doses did not caused any significant colour change. In general, the 2kGy dose favoured PUFA and was the most suitable to preserve the overall postharvest quality of fresh-cut watercress during cold storage. In turn, the 5kGy dose better preserved the antioxidant activity and total flavonoids and favoured MUFA, tocopherols and total phenolics, thus originating a final product with enhanced functional properties. Therefore, the suitability of gamma irradiation for preserving fresh-cut watercress quality during cold storage was demonstrated.


Assuntos
Temperatura Baixa , Conservação de Alimentos/métodos , Armazenamento de Alimentos , Raios gama , Nasturtium/efeitos da radiação , Relação Dose-Resposta à Radiação , Nasturtium/química
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