30 research outputs found
Integrated Green Chemical Approach to the Medicinal Plant Carpobrotus edulis Processing
Associate Laboratory for Green Chemistry (LAQV), which is financed by national funds from FCT/MCTES (UID/QUI/50006/2019).Many plants have medicinal properties due to substances known as phytochemicals. To utilize these plants in practice, numerous procedures, such as extraction, isolation and characterization methods and toxicology and bioactivity studies, must be designed and implemented. Integrated approach to process Carpobrotus edulis, a weed medicinal plant widely spread in Portugal, was developed into a closed loop of two processes: microwave assisted extraction (MAE) and activation (MAA), to produce both phytochemicals and biochar. The use of MAE for phytochemical extraction was shown to be more energy efficient than conventional Soxhlet extraction: the process time was decreased by 7–8 times, and the energy efficiency was increased by up to 97%. The yield of the extracts is of 27%. Qualitative and quantitative identification/characterization of the phytochemicals were performed by LC-MS and phytochemical screening assays. The results clearly indicated that Carpobrotus edulis is rich by flavonoids (up to 24%). The use of MAA to process the residual biomass could shorten the activation time, resulting in reduced energy consumption. Biochar with a high yield of 65% (on a biomass basis) and a well-developed texture (surface area of 68.9 m2/g; total pore volume of 0.10 cm3/g; micropore volume of 0.07 cm3/g) is obtained.publishersversionpublishe
A step forward
Funding: Authors gratefully acknowledge Fundação para a Ciência e a Tecnologia (FCT) through projects UIDB/00645/2020, UIDB/04138/2020, PTDC/MED-QUI/31721/2017, UIDP/04138/2020 and Lusófona University, ULHT. Authors are also thankful to FCT/MCTES for the financial support to CESAM (UIDP/50017/2020, UIDB/50017/2020), through national funds.Anaplastic thyroid carcinoma (ATC) is a very rare subtype of thyroid carcinoma and one of the most lethal malignancies. Poor prognosis is mainly associated with its undifferentiated nature, inoperability, and failing to respond to the typically used therapies for thyroid cancer. Photothermal Therapy (PTT) entails using light to increase tissues’ temperature, leading to hyperthermia-mediated cell death. Tumours are more susceptible to heat as they are unable to dissipate it. By using functionalized gold nanoparticles (AuNPs) that transform light energy into heat, it is possible to target the heat to the tumour. This study aims to formulate ATC-targeted AuNPs able to convert near-infrared light into heat, for PTT of ATC. Different AuNPs were synthetized and coated. Size, morphology, and surface plasmon resonances band were determined. The optimized coated-AuNPs were then functionalized with ligands to assess ATC’s specificity. Safety, efficacy, and selectivity were assessed in vitro. The formulations were deemed safe when not irradiated (>70% cell viability) and selective for ATC. However, when irradiated, holo-transferrin-AuNPs were the most cytotoxic (22% of cell viability). The biodistribution and safety of this formulation was assessed in vivo. Overall, this novel formulation appears to be a highly promising approach to evaluate in a very near future.publishersversionpublishe
How can biomolecules improve mucoadhesion of oral insulin? A comprehensive insight using ex-vivo, in silico and in vivo models
Currently, insulin can only be administered through the subcutaneous route. Due to the flaws associated with this route, it is of interest to orally deliver this drug. However, insulin delivered orally has several barriers to overcome as it is degraded by the stomach’s low pH, enzymatic content, and poor absorption in the gastrointestinal tract. Polymers with marine source like chitosan are commonly used in nanotechnology and drug delivery due to their biocompatibility and special features. This work focuses on the preparation and characterization of mucoadhesive insulin-loaded polymeric nanoparticles. Results showed a suitable mean size for oral administration (<600 nm by dynamic laser scattering), spherical shape, encapsulation efficiency (59.8%), and high recovery yield (80.6%). Circular dichroism spectroscopy demonstrated that protein retained its secondary structure after encapsulation. Moreover, the mucoadhesive potential of the nanoparticles was assessed in silico and the results, corroborated with ex-vivo experiments, showed that using chitosan strongly increases mucoadhesion. Besides, in vitro and in vivo safety assessment of the final formulation were performed, showing no toxicity. Lastly, the insulin-loaded nanoparticles were effective in reducing diabetic rats’ glycemia. Overall, the coating of insulin-loaded nanoparticles with chitosan represents a potentially safe and promising approach to protect insulin and enhance peroral delivery.Supported in part by UID/DTP/04138/2019 from FCT, Portugal and DREAMS (ULHT). SEM analysis was funded by FCT/MCTES for the financial support to CESAM (UIDP/50017/2020+UIDB/50017/2020), through national funds.
Acknowledgments: The authors are grateful to the Carla Vânia (iMedUlisboa) for her collaboration in HPLC analysis and Joana Moreira (ECTS-ULHT) for her collaboration in conducting some experiments.info:eu-repo/semantics/publishedVersio
International circular economy strategies and their impacts on agricultural water use
Publisher Copyright: © 2022 The AuthorsThe concept of Circular Economy (CE) is becoming increasingly important in the pursuit of more sustainable societies. CE strategies are being applied in the sustainable management of a plethora of areas, such as energy, water, food and eco-industrial parks. The present paper focuses on the question of how CE principles can support the sustainable management of water in the agricultural sector around the world, considering different legislative environments, water resources management guidelines, environmental stressors, and CE practices. Considering these practices and circumstances, seven countries were compared: Brazil, Germany, Japan, Mexico, Morocco, Portugal, and Taiwan. Together, CE experts in the seven countries developed a set of 44 criteria to assess each of these areas. Broader establishment and respect of water resources legislation was found to be strongly correlated with lower agricultural water use. While the application of CE practices was found to not be correlated with lower consumption, this is still novel in most countries. Based on the studied countries, it can be concluded that a global CE agenda has not been reached for water resources. Further application and variety of practices is required to better represent the impact of CE on a national scale, but local success stories could support the wider application of CE in agriculture. The findings and the framework of the study can be applied to other countries in directing CE strategies for more sustainable water use in agriculture. Increasing CE implementation, motivated by legislation and better management can help ensure water security throughout nations.publishersversionpublishe
How can biomolecules improve mucoadhesion of oral insulin? A comprehensive insight using ex-vivo, in silico, and in vivo models
Funding: Supported in part by UID/DTP/04138/2019 from FCT, Portugal and DREAMS (ULHT). SEM analysis was funded by FCT/MCTES for the financial support to CESAM (UIDP/50017/2020+UIDB/50017/2020), through national funds.Currently, insulin can only be administered through the subcutaneous route. Due to the flaws associated with this route, it is of interest to orally deliver this drug. However, insulin delivered orally has several barriers to overcome as it is degraded by the stomach’s low pH, enzymatic content, and poor absorption in the gastrointestinal tract. Polymers with marine source like chitosan are commonly used in nanotechnology and drug delivery due to their biocompatibility and special features. This work focuses on the preparation and characterization of mucoadhesive insulin-loaded polymeric nanoparticles. Results showed a suitable mean size for oral administration (<600 nm by dynamic laser scattering), spherical shape, encapsulation efficiency (59.8%), and high recovery yield (80.6%). Circular dichroism spectroscopy demonstrated that protein retained its secondary structure after encapsulation. Moreover, the mucoadhesive potential of the nanoparticles was assessed in silico and the results, corroborated with ex-vivo experiments, showed that using chitosan strongly increases mucoadhesion. Besides, in vitro and in vivo safety assessment of the final formulation were performed, showing no toxicity. Lastly, the insulin-loaded nanoparticles were effective in reducing diabetic rats’ glycemia. Overall, the coating of insulin-loaded nanoparticles with chitosan represents a potentially safe and promising approach to protect insulin and enhance peroral delivery.publishersversionpublishe
Estrogenic activity, selected plasticizers and potential health risks associated with bottled water in South Africa
Potential endocrine disrupting chemicals (EDCs) are present in bottled water from various countries. In South Africa (SA), increased bottled water consumption and concomitant increases in plastic packaging create important consequences for public health. This study aimed to screen SA bottled water for estrogenic activity, selected target chemicals and assessing potential health risks. Ten bottled water brands were exposed to 20 °C and 40 °C over 10 days. Estrogenic activity was assessed using the recombinant yeast estrogen screen (YES) and the T47D-KBluc reporter gene assay. Solid phase extracts of samples were analyzed for bis(2-ethylhexyl) adipate (DEHA), selected phthalates, bisphenol-A (BPA), 4-nonylphenol (4-NP), 17β-estradiol (E2), estrone (E1), and ethynylestradiol (EE2) using gas chromatography–mass spectrophotometry. Using a scenario-based health risk assessment, human health risks associated with bottled water consumption were evaluated. Estrogenic activity was detected at 20 °C (n = 2) and at 40 °C (n = 8). Estradiol equivalent (EEq) values ranged from 0.001 to 0.003 ng/L. BPA concentrations ranged from 0.9 ng/L to 10.06 ng/L. Although EEqs and BPA concentrations were higher in bottled water stored at 40 °C compared to 20 °C, samples posed an acceptable risk for a lifetime of exposure. Irrespective of temperature, bottled water from SA contained chemicals with acceptable health risks.The Cancer
Association of South Africa (CANSA).http://jwh.iwaponline.comhj2019School of Health Systems and Public Health (SHSPH
Effects of water potential on spore germination and viability of Fusarium species
Germination of macroconidia and/or microconidia of 24 strains of Fusarium solani, F. chlamydosporum, F. culmorum, F. equiseti, F. verticillioides, F. sambucinum, F. oxysporum and F. proliferatum isolated from fluvial channels and sea beds of the south-eastern coast of Spain, and three control strains (F. oxysporum isolated from affected cultures) was studied in distilled water in response to a range of water potentials adjusted with NaCI. (0, -13.79, -41.79, -70.37, -99.56 and -144.54 bars). The vialibility (UFC/ml) of suspension was also tested in three time periods (0,24 and 48h). Conidia always germinated in distilled water. The pattern of conidial germination obseved of F. verticillioides, F. oxysporum, F. proliferatum, F. chlamydosporum and F. culmorum was similar. A great diminution of spore germination was found in -13.79 bars solutions. Spore germination percentage for F. solani isolates was maximal at 48 h. and -13.79 bars with 21.33% spore germination, 16% higher than germination in distilled water. F. equiseti shows the maximum germination percentage in -144.54 bars solution in 24 h time with 12.36% germination. These results did not agree with those obtained in the viability test where maximum germination was found in distilled water. The viability analysis showed the great capacity of F. verticilloides strains to form viable colonies, even in such extreme conditions as -144,54 bars after 24 h F. proliferatum colony formation was prevented in the range of -70.37 bars. These results show the clear affectation of water potential to conidia germination of Fusaria. The ability of certain species of Fusarium to develop a saprophytic life in the salt water of the Mediterraneam Sea could be certain. Successful germination, even under high salty media conditions, suggests taht Fusarium spp. could have a competitive advantage over other soil fungi in crops irrigated with saline water. In the specific case of F. solani, water potential of -13.79 bars affected germination positively. It could indicate that F. solani has an special physiological mechanism of survival in low water potential environments
Role of a conserved arginine residue during catalysis in serine palmitoyltransferase
AbstractAll sphingolipid-producing organisms require the pyridoxal 5′-phosphate (PLP)-dependent serine palmitoyltransferase (SPT) to catalyse the first reaction on the de novo sphingolipid biosynthetic pathway. SPT is a member of the alpha oxoamine synthase (AOS) family that catalyses a Claisen-like condensation of palmitoyl-CoA and l-serine to form 3-ketodihydrosphingosine (KDS). Protein sequence alignment across various species reveals an arginine residue, not involved in PLP binding, to be strictly conserved in all prokaryotic SPTs, the lcb2 subunits of eukaryotic SPTs and all members of the AOS family. Here we use UV–vis spectroscopy and site-directed mutagenesis, in combination with a substrate analogue, to show that the equivalent residue (R370) in the SPT from Sphingomonas wittichii is required to form the key PLP:l-serine quinonoid intermediate that condenses with palmitoyl-CoA and thus plays an essential role enzyme catalysis.Structured summary of protein interactionsSPT binds to SPT by molecular sieving (View interaction