João E.B. Tavares

Dr. João E.B. Tavares

Bioenergy and Biorefinery Unit, National Laboratory of Energy and Geology, Lisbon, Lisboa, Portugal
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Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

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

Representative Publications

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3 December 2010 in Journal of Ethnobiology and Ethnomedicine
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Journal Article
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ANA RIBEIRO-BARROSANA RIBEIRO-BARROS
ANA RIBEIRO-BARROS
Maria RomeirasMaria Romeiras
Maria Romeiras
João E.B. TavaresJoão E.B. Tavares
João E.B. Tavares
MFMaria T Faria
Maria T Faria
Background: Medicinal plants are used by 80% of people from developing countries to fulfill their primary health needs, occupying a key position on plant research and medicine. Taking into account that, besides their pharmaceutical importance, these plants contribute greatly to ecosystems' stability, a continuous documentation and preservation of traditional knowledge is a priority. The objective of this study was to organize a database of medicinal plants including their applications and associated procedures in Canhane village, district of Massingir, province of Gaza, Mozambique. Methods: In order to gather information about indigenous medicinal plants and to maximize the collection of local knowledge, eleven informants were selected taking into account the dimension of the site and the fact that the vegetation presents a great homogeneity. The data were collected through intensive structured and semi-structured interviews performed during field research. Taxonomical identification of plant species was based on field observations and herbarium collections. Results: A total of 53 plant species have been reported, which were used to treat 50 different human health problems. More than half of the species were used for stomach and intestine related disturbances (including major diseases such as diarrhea and dysentery). Additionally, four species with therapeutic applications were reported for the first time, whose potential can further be exploited. The great majority of the identified species was also associated with beliefs and myths and/or used as food. In general, the community was conscientious and motivated about conservational issues and has adopted measures for the rational use of medicinal plants. Conclusions: The ethnomedicinal use of plant species was documented in the Canhane village. The local community had a rich ethnobotanical knowledge and adopted sound management conservation practices. The data compiled in this study show the social importance of the surveyed plants being a contribution to the documentation of PGR at the national and regional level.

25 April 2022 in Processes
Verified
Journal Article
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TSTiago Silva
Tiago Silva
SASusana M. T. Paixão Alves
Susana M. T. Paixão Alves
João E.B. TavaresJoão E.B. Tavares
João E.B. Tavares
CGCátia Gil
Cátia Gil
Cristiana A. V. TorresCristiana A. V. Torres
Cristiana A. V. Torres
LALuís Alves
Luís Alves
Biosurfactants and bioemulsifiers (BS/BE) are naturally synthesized molecules, which can be used as alternatives to traditional detergents. These molecules are commonly produced by microorganisms isolated from hydrocarbon-rich environments. Gordonia alkanivorans strain 1B was originally found in such an environment, however little was known about its abilities as a BS/BE producer. The goal of this work was to access the potential of strain 1B as a BS/BE producer and perform the initial characterization of the produced compounds. It was demonstrated that strain 1B was able to synthesize lipoglycoprotein compounds with BS/BE properties, both extracellularly and adhered to the cells, without the need for a hydrophobic inducer, producing emulsion in several different hydrophobic phases. Using a crude BS/BE powder, the critical micelle concentration was determined (CMC = 16.94 mg/L), and its capacity to reduce the surface tension to a minimum of 35.63 mN/m was demonstrated, surpassing many commercial surfactants. Moreover, after dialysis, emulsification assays revealed an activity similar to that of Triton X-100 in almond and sunflower oils. In benzene, the E24 value attained was 83.45%, which is 30% greater than that of the commercial alternative. The results obtained highlight for the presence of promising novel BS/BE produced by strain 1B.

1 December 2021 in Colloids and Surfaces B: Biointerfaces
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Journal Article
Closed access
João E.B. TavaresJoão E.B. Tavares
João E.B. Tavares
LALuís Alves
Luís Alves
TSTiago P. Silva
Tiago P. Silva
SASusana M. T. Paixão Alves
Susana M. T. Paixão Alves

6 February 2018 in New Journal of Chemistry
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Journal Article
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João E.B. TavaresJoão E.B. Tavares
João E.B. Tavares
Rafał M. LukasikRafał M. Lukasik
Rafał M. Lukasik
TPTeresa Cristina Brazil de Paiva
Teresa Cristina Brazil de Paiva
FSFlávio Teixeira da Silva
Flávio Teixeira da Silva
Integration of hydrothermal and alkaline processing in the formation of upgradable sugars for advanced processing of sugarcane bagasse residues.

7 February 2023 in Journal of Environmental Management
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Journal Article
Closed access
João E.B. TavaresJoão E.B. Tavares
João E.B. Tavares
TSTiago P. Silva
Tiago P. Silva
SASusana M. T. Paixão Alves
Susana M. T. Paixão Alves
LALuís Alves
Luís Alves

27 August 2025 in Chemengineering
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Journal Article
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João E.B. TavaresJoão E.B. Tavares
João E.B. Tavares
Abdelwahab RaiAbdelwahab Rai
Abdelwahab Rai
TPTeresa Cristina Brazil de Paiva
Teresa Cristina Brazil de Paiva
FSFlávio Teixeira da Silva
Flávio Teixeira da Silva
Bioethanol from sugarcane bagasse is a promising second-generation biofuel due to its abundance as a sugar industry by-product. Herein, enzymatic hydrolysate obtained from sugarcane bagasse pretreated with optimized hydrothermal alkaline sulfite (HAS) was evaluated for its fermentability using Saccharomyces cerevisiae PE-2 and Scheffersomyces stipitis CBS 5773. The HAS pretreatment achieved a high delignification rate (63%), resulting in a cellulose- and hemicellulose-enriched substrate (55% and 27%, respectively). While the cellulose content remained relatively constant, hemicellulose content was reduced by 25%, with significant removal of acetyl groups (80%) and arabinan groups (39%). The pretreated bagasse exhibited high digestibility, applying 10 FPU (filter paper unit) cellulase together with 10 CBU (cellobiose unit) β-glucosidase per gram of dry bagasse in the hydrolysis step, yielding 72% glucan and 66% xylan conversion within 72 h. The resulting hydrolysate was efficiently fermented by S. cerevisiae and S. stipitis, achieving ethanol yields of 0.51 and 0.43 g/g of sugars, respectively. The fermentation kinetics were comparable to those observed in a synthetic medium containing pure sugars, demonstrating the effectiveness of HAS pretreatment in generating readily fermentable, carbohydrate-rich substrates. HAS pretreatment enabled improved conversion of sugarcane bagasse into fermentation-ready sugars, constituting a potential resource for bioethanol synthesis applying both S. cerevisiae and S. stipitis in the future.