Search results for "microalga"
showing 10 items of 135 documents
Model performance of partial least squares in utilizing the visible spectroscopy data for estimation of algal biomass in a photobioreactor
2018
[EN] Spectroscopy technology and statistical methods (Partial Least Squares) have been integrated to develop a model that allows estimating the microalgal biomass in a photobioreactor. The model employing PLS combines the absorption spectrum measurements in the visible range (400-750 nm) with a microalgae cell density in a water sample. First, a calibration model was constructed using a calibration data set, and then, the predictive capacity of the model was determined by cross validation. Finally, an external validation of the predictive performance of the model was carried out with an independent data set. To test the accuracy of the model it was applied to different culture conditions yi…
Degradación de Disruptores Endocrinos de Estructura Fenólica en Procesos de Tratamiento de Aguas Residuales
2015
El trabajo recogido tanto en los resultados como en las conclusiones de la presente tesis está encaminado a esclarecer el comportamiento de algunos de los microcontaminantes orgánicos incluidos en la Directiva 2000/60/CE bajo diversas condiciones de trabajo en estaciones depuradoras de aguas residuales. Para ello se ha estudiado un grupo de microcontaminantes cuya presencia en el medio ambiente, bien sea en la fracción soluble de las aguas continentales o bioacumulados en sedimentos y/o biota, es frecuente. La presencia de dichos compuestos es debida, fundamentalmente, a la industrialización y a los actuales hábitos de la sociedad. Los microcontaminantes tipo elegidos son: octilfenol, 4-n-n…
Biodiversity Patterns and Ecological Preferences of the Photobionts Associated With the Lichen-Forming Genus Parmelia
2021
The worldwide, ecologically relevant lichen-forming genusParmeliacurrently includes 41 accepted species, of which theParmelia sulcatagroup (PSULgp) and theParmelia saxatilisgroup (PSAXgp) have received considerable attention over recent decades; however, phycobiont diversity is poorly known inParmelias. lat. Here, we studied the diversity ofTrebouxiamicroalgae associated with 159 thalli collected from 30 locations, including nineParmeliaspp.:P. barrenoae, P. encryptata, P. ernstiae, P. mayi, P. omphalodes, P. saxatilis, P. serrana, P. submontana, andP. sulcata. The mycobionts were studied by carrying out phylogenetic analyses of the nrITS. Microalgae genetic diversity was examined by using …
Pulsed electric field (PEF) recovery of biomolecules from Chlorella: Extract efficiency, nutrient relative value, and algae morphology analysis
2023
This study investigated the effects of pulsed electric field (PEF) (3 kV/cm, 44 pulses, 99 kJ/kg), solvent (H2O or 50 % DMSO) and time (0, 10, 20, 30, 60, 90, 120 and 180 min) on the extraction of Chlorella antioxidant biomolecules and minerals. The results showed that PEF treatment increased the biomolecules recovery. For the extraction time of 120 min, more proteins and polyphenols were obtained using water, while more chlorophyll a and b, and carotenoids were obtained using 50 % DMSO as the extraction solvent. The extracts mineral concentration (PEF vs control) were analysed including Mg, P, Ca, Fe and Zn, and the Relative Nutrient Values results indicated that Chlorella H2O-extracts cou…
The impact of liquid-pressurized extracts of Spirulina, Chlorella and Phaedactylum tricornutum on in vitro antioxidant, antiinflammatory and bacteria…
2022
The impact of Spirulina, Chlorella and Phaeodactylum tricornutum (P. tricornutum) microalgal extracts obtained by pressurized liquid extraction (PLE) on antioxidant and anti-inflammatory activities, microbial growth and in vitro gut microbiota composition was evaluated. PLE, compared to conventional extraction, led to a significant (p < 0.05) increase in proteins, carbohydrates, polyphenols, and antioxidant capacities of the three microalgal extracts. Moreover, Spirulina and P. tricornutum extracts significantly (p < 0.05) reduced the in vitro activation of the inflammatory NF-κB pathway. The microalgal extracts had also an inhibitory effect on the pathogenic bacteria while potential benefi…
Comparing in vivo data and in silico predictions for acute effects assessment of biocidal active substances and metabolites for aquatic organisms.
2020
Abstract The purpose of this study was to determine the acute toxicity in aquatic organisms of one biocidal active substance and six metabolites derived from biocidal active substances and to assess the suitability of available QSAR models to predict the obtained values. We have reported the acute toxicity in sewage treatment plant (STP) microorganisms, in the freshwater microalgae Pseudokirchneriella subcapitata and in Daphnia magna following OECD test methods. We have also identified in silico models for acute toxicity of these trophic levels currently available in widely recognized platforms such as VEGA and the OECD QSAR ToolBox. A total of six, four and two models have been selected fo…
Autochthonous microalgae grown in municipal wastewaters as a tool for effectively removing nitrogen and phosphorous
2020
Abstract Microalgae have promising applications in wastewater treatment because of their ability to use inorganic compounds such as nitrates and phosphates as nutrients for their growth. Microalgae are applied to the secondary and tertiary bio-treatment with two benefits: i) pollutants removal from wastewater; ii) production of microalgal biomass, that can be exploited as a source of biomass and biomolecules. In the present work, four different microalgal strains (two from culture collections and two isolated from Sicilian littoral) were tested in municipal sewage bioremediation. The sewage of a municipal plant, already processed with primary treatment, was used for the cultivation of micro…
The proitability of microalgae biomass farming in Mediterranean environments
2015
The aims of the present study was to assess the economic sustainability of microalgae cultivation in PBRs, ascertain in what conditions of productivity and price it is possible to achieve similar results to those of the irst case, and assess the impact that the results of plant management could have on the balance sheets of farms which may have an interest in expanding their production. Our results show shows that, while prospects are encouraging, there is a need to develop structured supply chains able to confer greater stability to the market and to ensure a higher degree of certainty to stakeholders.
A century of research on micro-organisms from the inland waters of the largest mediterranean island
2022
The first studies on the micro-organisms inhabiting Sicilian inland waters date back to the middle of the XIX century. However, these were based on single samples and mainly addressed at compiling faunistic and floristic inventories. It was in the first decades of the XX century that the first methodical studies were performed, which focussed on assessing microbial diversity in saline and hypersaline inland waters. Studies on plankton dynamics in ponds and reservoirs of the island started at the beginning of the 1980s and, since the end of the 1990s, temporary waters have also been intensively sampled, especially as regards phytoplankton and micro-crustaceans. These intensified sampling eff…
MODELLING OF THE GROWTH OF NANNOCHLOROPSIS GADITANA IN DIFFERENT REACTOR GEOMETRIES, EXPERIMENTAL KINETIC PARAMETERS FROM BATCH CULTURES AND BIOCHEMI…
2022
Microalgae are unicellular and photosynthetic microorganisms that grow using inorganic salts, CO2 and light, and are applied in numerous industrial sectors due to their variety and properties. Due to the lack of information on how microalgae respond to external inputs and to the different environments in which they grow, today the industrial application is not exploited as it should. It is therefore necessary to create models that allow to predict microalgal growth in different photobioreactors to improve our knowledge, still poorly investigated. In this work the Monod equation for the specific growth rate was combined with the Lambert-Beer law for the non-homogeneous light distribution in …