Alexandra Sofia Esteves

Prof. Alexandra Sofia Esteves

Veterinary Science, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
orcid

Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 September 2022 in Foods
Verified
Journal Article
Open access
PDF file
RMRui Pedro Rio Martins
Rui Pedro Rio Martins
Liliana SilvaLiliana Silva
Liliana Silva
André PereiraAndré Pereira
André Pereira
AEAlexandra Sofia Esteves
Alexandra Sofia Esteves
SDSofia Duarte
Sofia Duarte
Angelina Lopes Simões PenaAngelina Lopes Simões Pena
Angelina Lopes Simões Pena
Coccidiosis remains one of the major problems of the poultry industry. Caused by Eimeria species, Coccidiosis is a contagious parasitic disease affecting poultry with great economic significance. Currently, in order to prevent health problems caused by this disease, broiler farmers make extensive use of coccidiostats in poultry feed, maintaining animal health and, in some cases, enhancing feed conversion. The presence of unauthorized substances, residues of veterinary products and chemical contaminants in the food industry is of concern, since they may pose a risk to public health. As the use of coccidiostats has been increasing without any requirements for veterinary prescription, research and surveillance of coccidiostat residues in poultry meat is becoming imperative. This review presents an up-to-date comprehensive discussion of the state of the art regarding coccidiosis, the most used anticoccidials in poultry production, their mode of action, their prophylactic use, occurrence and the European Union (EU) applicable legislation.

7 June 2023 in Foods
Verified
Journal Article
Open access
PDF file
Márcio Moura-AlvesMárcio Moura-Alves
Márcio Moura-Alves
AEAlexandra Sofia Esteves
Alexandra Sofia Esteves
MCMaria Ciríaco
Maria Ciríaco
JSJosé António Silva
José António Silva
Cristina Maria SaraivaCristina Maria Saraiva
Cristina Maria Saraiva
Meat deterioration during processing, distribution, and display can compromise the quality and safety of products, causing several undesirable changes and decreasing products’ shelf-life, which has a negative impact on the industry and consumers. In recent years, studies have been carried out using decontamination techniques and new packaging methodologies to overcome deterioration problems, increase sustainability, and reduce waste. Edible films and coatings obtained from biopolymers such as polysaccharides, proteins, and lipids, combined with active compounds, can be an alternative approach. This article focused on recent studies that used alternative biodegradable polymeric matrices in conjunction with natural compounds with antioxidant/antimicrobial activity on chicken meat. Its impact on physicochemical, microbiological, and sensory characteristics was evident, as well as the effect on its shelf-life. In general, different combinations of active edible films or coatings had a positive effect on the chicken meat. Different studies reported that the main results were a decrease in microbial growth and pathogen survival, a slowdown in lipid oxidation evolution, and an improvement in sensory quality and shelf-life (an increase from 4 to 12 days).

21 March 2021 in Biomolecules
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Journal Article
Open access
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MOMaria Leonor Orge
Maria Leonor Orge
CLCarla Lima
Carla Lima
CMCarla Machado
Carla Machado
PTPaula Tavares
Paula Tavares
AFAna Fortuna
Ana Fortuna
MPMaria dos Anjos Pires
Maria dos Anjos Pires
Transmissible Spongiform Encephalopathies (TSEs) or prion diseases are a fatal group of infectious, inherited and spontaneous neurodegenerative diseases affecting human and animals. They are caused by the conversion of cellular prion protein (PrPC) into a misfolded pathological isoform (PrPSc or prion- proteinaceous infectious particle) that self-propagates by conformational conversion of PrPC. Yet by an unknown mechanism, PrPC can fold into different PrPSc conformers that may result in different prion strains that display specific disease phenotype (incubation time, clinical signs and lesion profile). Although the pathways for neurodegeneration as well as the involvement of brain inflammation in these diseases are not well understood, the spongiform changes, neuronal loss, gliosis and accumulation of PrPSc are the characteristic neuropathological lesions. Scrapie affecting small ruminants was the first identified TSE and has been considered the archetype of prion diseases, though atypical and new animal prion diseases continue to emerge highlighting the importance to investigate the lesion profile in naturally affected animals. In this report, we review the neuropathology and the neuroinflammation of animal prion diseases in natural hosts from scrapie, going through the zoonotic bovine spongiform encephalopathy (BSE), the chronic wasting disease (CWD) to the newly identified camel prion disease (CPD).

9 November 2023 in Foods
Verified
Journal Article
Open access
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Márcio Moura-AlvesMárcio Moura-Alves
Márcio Moura-Alves
Victor Gomes Lauriano SouzaVictor Gomes Lauriano Souza
Victor Gomes Lauriano Souza
JSJosé António Silva
José António Silva
AEAlexandra Sofia Esteves
Alexandra Sofia Esteves
Lorenzo  M. PastranaLorenzo M. Pastrana
Lorenzo M. Pastrana
Miguel CerqueiraMiguel Cerqueira
Miguel Cerqueira
Due to environmental concerns, there is an increasing need to reduce the use of synthetic and non-renewable packaging materials to reduce waste and increase sustainability. This study aimed to characterise sodium alginate edible-based films (SA) incorporated with laurel leaf extract (LLE) and olive leaf extract (OLE) obtained by ultrasound-assisted extraction. Determination of total phenolic content, antioxidant, and antimicrobial activity was performed for the extracts and films. Also, thickness, tensile strength, elongation at break, modulus of elasticity, opacity and colour, moisture content, water vapour permeability (WVP), Fourier-transform infrared spectroscopy (FTIR) spectra, and surface morphology by scanning electron microscope (SEM) analyses were performed for the films. LLE yielded better results in terms of phenolic content (195 mg GAE/g), antioxidant (2.1 TE/g extract) and antimicrobial activity (MIC at 1% for Listeria monocytogenes and Staphylococcus aureus, and 1.8% for Enterococcus faecalis). For the films, the simultaneous incorporation of LLE 1% (w/v) and OLE 1% (w/v) resulted in a significant reduction of approximately 2 log CFU/g against S. aureus. The addition of LLE and OLE extracts also proved to improve barrier properties (lower WVP for SA films with LLE 1% + OLE 1%, 3.49 × 10−11 g m−1 s−1 Pa−1) and promoted changes in resistance and flexibility. The results demonstrated that active alginate-based films can be valuable for enhancing food preservation.

1 December 2013 in Food Control
Verified
Journal Article
Closed access
KSKamila Soares
Kamila Soares
JGJuan García-Díez
Juan García-Díez
AEAlexandra Sofia Esteves
Alexandra Sofia Esteves
Irene Cristina OliveiraIrene Cristina Oliveira
Irene Cristina Oliveira
Cristina Maria SaraivaCristina Maria Saraiva
Cristina Maria Saraiva

14 May 2024 in Antibiotics
Verified
Journal Article
Open access
PDF file
ASAdriana Silva
Adriana Silva
Vanessa SilvaVanessa Silva
Vanessa Silva
João Paulo GomesJoão Paulo Gomes
João Paulo Gomes
CCCoelho Coelho
Coelho Coelho
RBRita Batista
Rita Batista
Patrícia PoetaPatrícia Poeta
Patrícia Poeta
Listeria monocytogenes, a foodborne pathogen, exhibits high adaptability to adverse environmental conditions and is common in the food industry, especially in ready-to-eat foods. L. monocytogenes strains pose food safety challenges due to their ability to form biofilms, increased resistance to disinfectants, and long-term persistence in the environment. The aim of this study was to evaluate the presence and genetic diversity of L. monocytogenes in food and related environmental products collected from 2014 to 2022 and assess antibiotic susceptibility and biofilm formation abilities. L. monocytogenes was identified in 13 out of the 227 (6%) of samples, 7 from food products (meat preparation, cheeses, and raw milk) and 6 from food-processing environments (slaughterhouse-floor and catering establishments). All isolates exhibited high biofilm-forming capacity and antibiotic susceptibility testing showed resistance to several classes of antibiotics, especially trimethoprim-sulfamethoxazole and erythromycin. Genotyping and core-genome clustering identified eight sequence types and a cluster of three very closely related ST3 isolates (all from food), suggesting a common contamination source. Whole-genome sequencing (WGS) analysis revealed resistance genes conferring resistance to fosfomycin (fosX), lincosamides (lin), fluoroquinolones (norB), and tetracycline (tetM). In addition, the qacJ gene was also detected, conferring resistance to disinfecting agents and antiseptics. Virulence gene profiling revealed the presence of 92 associated genes associated with pathogenicity, adherence, and persistence. These findings underscore the presence of L. monocytogenes strains in food products and food-associated environments, demonstrating a high virulence of these strains associated with resistance genes to antibiotics, but also to disinfectants and antiseptics. Moreover, they emphasize the need for continuous surveillance, effective risk assessment, and rigorous control measures to minimize the public health risks associated to severe infections, particularly listeriosis outbreaks. A better understanding of the complex dynamics of pathogens in food products and their associated environments can help improve overall food safety and develop more effective strategies to prevent severe health consequences and economic losses.