18 documents found, page 1 of 2
Influence of bacterial load on the development and performance of a photohetero...
Sousa, Henrique; Simões, Lúcia Chaves; Sousa, Cátia A.; Simões, ManuelA novel photoheterotrophic dual-species biofilm was evaluated for wastewater (WW) treatment and microbial growth under variable cell loads. For that, Chlorella vulgaris was tested under axenic conditions and in combination with three bacteria, Rhodococcus fascians, Acinetobacter calcoaceticus, and Leucobacter sp., assessing the influence of each bacterial strain in biomass productivity, growth rate, thickness, ...
Synergistic bactericidal combinations: far-UV-C, mechanical cleaning and chlori...
Sousa, Mariana; Oliveira, Isabel M.; Correia, Liliana; Gomes, Inês B.; Sousa, Cátia A.; F. O. Braga, Daniel; Simões, ManuelBackground: The issue of indoor contamination stands as a global health challenge, contributing to the spread of infectious diseases [1,2]. Consequently, there is an urgent need to explore new disinfection strategies that rely on reduced concentrations of conventional cleaning chemicals [3,4]. Objective: This study aimed to explore innovative disinfection approaches utilizing far-UV-C (222 nm) radiation al...
Carbon dots de síntese única para deteção de espécies reativas de oxigénio
Almeida, Lícia; Sousa, Cátia A.; Duarte, Abel J.(Introdução) As espécies reativas de oxigénio (reactive oxygen species – ROS), são um conjunto de radicais livres que derivam do oxigénio e provêm da cadeia respiratória. São de importância vital nos organismos vivos em quantidade muito reduzidas, funcionando como neurotransmissores ou vasodilatadores, no entanto, quando em grandes quantidades provocam o stresse oxidativo causador de inúmeras patologias. A dete...
Polluted Rivers—A Case Study in Porto, Portugal
Lemos, Patrícia; Silva, Paulo; Sousa, Cátia A.; Duarte, Abel J.; A. Sousa, Cátia; Duarte, Abel J.River contamination by microorganisms, or another chemical source, poses a serious threat to both the environment and public health. Taking immediate and appropriate actions is essential to mitigate the contamination and prevent further spread. As such, regular monitoring of these pollution agents is essential to act in time and control its minor extension. However, there is a lack of commitment to this emergen...
Strenghten the nutrients in aquaponics
Martins, Camila O.; Sousa, Miguel; Ferreira, Paulo; Sousa, Cátia A.; Duarte, Abel J.(Objectives) This work is aimed to develop chemical detection systems for some of the ions, such as nitrate, nitrite, or iron, adapting simple, robust and inexpensive electronic circuits for their monitoring, in order to achieve concentrations in real time.
Microalgal-based removal of contaminants of emerging concern
Sousa, Henrique; Sousa, Cátia A.; Simões, Lúcia Chaves; Simões, Manuel LopesThe presence of contaminants of emerging concern (CECs) in the environment has been recognized as a worldwide concern. In particular, water pollution by CECs is becoming a major global problem, which requires ongoing evaluation of water resources policies at all levels and the use of effective and innovative wastewaters treatment processes for their removal. Microalgae have been increasingly recognized as relev...
Metal(loid) oxide (Al2O3, Mn3O4, SiO2 and SnO2) nanoparticles cause cytotoxicit...
Sousa, Cátia A.; Soares, Helena M. V. M.; Soares, EduardoIn this work, the physicochemical characterization of five (Al2O3, In2O3, Mn3O4, SiO2 and SnO2) nanoparticles (NPs) was carried out. In addition, the evaluation of the possible toxic impacts of these NPs and the respective modes of action were performed using the yeast Saccharomyces cerevisiae. In general, in aqueous suspension, metal(loid) oxide (MOx) NPs displayed an overall negative charge and agglomerated; ...
Nickel Oxide Nanoparticles Trigger Caspase- and Mitochondria-Dependent Apoptosi...
Sousa, Cátia A.; Soares, Helena M. V. M.; Soares, Eduardo V.The expansion of the industrial use of nickel oxide (NiO) nanoparticles (NPs) raises concerns about their potential adverse effects. Our work aimed to investigate the mechanisms of toxicity induced by NiO NPs, using the yeast Saccharomyces cerevisiae as a cell model. Yeast cells exposed to NiO NPs exhibited typical hallmarks of regulated cell death (RCD) by apoptosis [loss of cell proliferation capacity (cell v...
Comparison of five bacterial strains producing siderophores with ability to che...
Ferreira, Carlos M. H.; Vilas-Boas, Ângela; Sousa, Cátia A.; Soares, Helena M. V. M.; Soares, Eduardo V.Iron deficiency is one of the main causes of chlorosis in plants, which leads to losses in field crops quality and yield. The use of synthetic chelates to prevent or correct iron-deficiency is not satisfactory mainly due to their poor biodegradability. The present work aimed to search suitable microorganisms to produce alternative, environment-friendly iron-chelating agents (siderophores). For this purpose, the...
Chronic exposure of the freshwater alga Pseudokirchneriella subcapitata to five...
Sousa, Cátia A.; Soares, Helena M.V.M.; Soares, Eduardo V.The increasing use of nanoparticles (NPs) unavoidably enhances their unintended introduction into the aquatic systems, raising concerns about their nanosafety. This work aims to assess the toxicity of five oxide NPs (Al2O3, Mn3O4, In2O3, SiO2 and SnO2) using the freshwater alga Pseudokirchneriella subcapitata as a primary producer of ecological relevance. These NPs, in OECD medium, were poorly soluble and unsta...