João Reboleira

Mr. João Reboleira

orcid

Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

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

Representative Publications

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14 February 2021 in Coatings
Verified
Journal Article
Open access
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Mariana AndradeMariana Andrade
Mariana Andrade
Cássia H. BarbosaCássia H. Barbosa
Cássia H. Barbosa
Victor Gomes Lauriano SouzaVictor Gomes Lauriano Souza
Victor Gomes Lauriano Souza
Isabel CoelhosoIsabel Coelhoso
Isabel Coelhoso
JRJoão Reboleira
João Reboleira
Fernando RamosFernando Ramos
Fernando Ramos
Algae and seaweeds are used in cookery since the beginnings of human civilization, particularly in several Asian cultures. Phenolic compounds are secondary metabolites produced by aquatic and terrestrial plants for their natural defense against external stimuli, which possess powerful antimicrobial and antioxidant properties that can be very important for the food industry. The main objective of this study was to develop a whey protein concentrate active coating, incorporated with a Fucus vesiculosus extract in order to delay the lipid oxidation of chicken breasts. Ten hydroethanolic extracts from F. vesiculosus were obtained and their antioxidant capacity was evaluated through two antioxidant activity assays: the DPPH radical scavenging activity and β-carotene bleaching assay. The total content in phenolics compounds was also determined by Folin-Ciocalteu method. The chosen extract was the one obtained from the freeze-dried F. vesiculosus using 75% (v/v) ethanol as extraction solvent. The extract was successfully incorporated into a whey protein film and successfully strengthened the thickness, tensile strength, and elastic modulus. The active film also was able to inhibit the chicken breasts lipid oxidation for 25 days of storage.

15 November 2021 in Pharmaceutics
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Journal Article
Open access
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Adriana P. JanuárioAdriana P. Januário
Adriana P. Januário
RFRafael Félix
Rafael Félix
CFCarina Félix
Carina Félix
JRJoão Reboleira
João Reboleira
Patricia ValentaoPatricia Valentao
Patricia Valentao
Marco F. L. LemosMarco F. L. Lemos
Marco F. L. Lemos
Acne vulgaris (AV) is a chronic skin disease of the pilosebaceous unit affecting both adolescents and adults. Its pathophysiology includes processes of inflammation, increased keratinization, sebum production, hormonal dysregulation, and bacterial Cutibacterium acnes proliferation. Common AV has been treated with antibiotics since the 1960s, but strain resistance has emerged and is of paramount concern. Macroalgae are known producers of substances with bioactive properties, including anti-viral, antibacterial, antioxidant, and anti-inflammatory properties, among several others. In particular, red algae are rich in bioactive compounds such as polysaccharides, phenolic compounds, lipids, sterols, alkaloids, and terpenoids, conferring them antioxidant, antimicrobial, and anti-inflammatory activities, among others. Thus, the exploration of compounds from marine resources can be an appealing approach to discover new treatment options against AV. The aim of this work is to provide an overview of the current knowledge of the potentialities of red macroalgae in the treatment of AV by reviewing the main therapeutic targets of this disease, and then the existence of compounds or extracts with bioactive properties against them.

1 January 2019
Verified
Book Chapter
Closed access
Joana SilvaJoana Silva
Joana Silva
Celso AlvesCelso Alves
Celso Alves
Susete PinteusSusete Pinteus
Susete Pinteus
JRJoão Reboleira
João Reboleira
RPRui Pedrosa
Rui Pedrosa
SBSusana Bernardino
Susana Bernardino

5 September 2020 in Molecules
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Journal Article
Open access
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JRJoão Reboleira
João Reboleira
RGRui Ganhão
Rui Ganhão
SMSusana Mendes
Susana Mendes
PAPedro Adão
Pedro Adão
Mariana AndradeMariana Andrade
Mariana Andrade
Susana BernardinoSusana Bernardino
Susana Bernardino
Incorporation of antioxidant agents in edible films and packages often relies in the usage of essential oils and other concentrated hydrophobic liquids, with reliable increases in antimicrobial and antioxidant activities of the overall composite, but with less desirable synthetic sources and extraction methods. Hydroethanolic extracts of commercially-available red macroalgae Gracilaria gracilis were evaluated for their antioxidant potential and phenolic content, as part of the selection of algal biomass for the enrichment of thermoplastic film coatings. The extracts were obtained through use of solid-liquid extractions, over which yield, DPPH radical reduction capacity, total phenolic content, and FRAP activity assays were measured. Solid-to-liquid ratio, extraction time, and ethanol percentages were selected as independent variables, and response surface methodology (RSM) was then used to estimate the effect of each extraction condition on the tested bioactivities. These extracts were electrospun into polypropylene films and the antioxidant activity of these coatings was measured. Similar bioactivities were measured for both 100% ethanolic and aqueous extracts, revealing high viability in the application of both for antioxidant coating purposes, though activity losses as a result of the electrospinning process were above 60% in all cases.

26 March 2020 in Coatings
Verified
Journal Article
Open access
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JRJoão Reboleira
João Reboleira
PAPedro Adão
Pedro Adão
SGSara Guerreiro
Sara Guerreiro
Juliana  DiasJuliana Dias
Juliana Dias
RGRui Ganhão
Rui Ganhão
Susana BernardinoSusana Bernardino
Susana Bernardino
Aqueous extracts of commercially available red macroalgae Porphyra dioica were integrated as inner coatings of food-grade polypropylene (PP) films through use of electrospinning and electrospraying technologies. Two coating formulations (A = 5 wt% P. dioica extract and 7.5 wt% polyvinyl alcohol (PVA); B = 1 wt% P. dioica extract, 1 wt% PVA, and 17% gelatine) were evaluated as to their capacity to delay spoilage of minced chicken breasts, through monitoring of microbial growth (total mesophile aerobic colony counts), colour stability, lipid oxidation (thiobarbituric acid reactive substances (TBARS)), and sensory analysis over a 4-day refrigerated storage. Scanning electron microscopy (SEM) imaging revealed an increased nanofiber and nanoparticle density on extract-enriched fibers, without compromise to their morphology or the homogeneity of the coatings. Total microbial counts on coating B samples was significantly (p < 0.001) reduced compared to uncoated plastic wraps. The coated samples also exhibited fewer colour degradation, though the coatings did not differ substantially from uncoated plastic wrap. Sensory analysis test subjects successfully distinguished the raw samples based on their treatment and gave a positive approval rating (66.7%) to the extract-enriched coatings when asked about edibility post storage.

1 January 2019
Verified
Book Chapter
Closed access
JRJoão Reboleira
João Reboleira
RFRafaela Freitas
Rafaela Freitas
Susete PinteusSusete Pinteus
Susete Pinteus
Joana SilvaJoana Silva
Joana Silva
Celso AlvesCelso Alves
Celso Alves
SBSusana Bernardino
Susana Bernardino